Professional Turf IPM Guide

Table of Contents

Introduction

The Professional Guide for IPM in Turf for Massachusetts is intended for use by Green Industry professionals as a tool in the care of all types of managed turf: from roadsides and utility areas, to lawns, to fine playing surfaces. Many of the principles presented are useful in a wide range of management schemes, from low-maintenance to high intensity care of premier turf sites. While a portion of the information is geared specifically to Massachusetts growing conditions or regulations, many of the approaches outlined are applicable to cool-season turf environments throughout New England and beyond.

The primary focus of this publication is turf pest management. The information contained in this guide is based on Integrated Pest Management (IPM) concepts; therefore some of the discussion extends beyond the direct control of pests. IPM is a decision making process that begins with a management plan and builds on proactive measures such as appropriate turfgrass selection and management fundamentals such as mowing, irrigation and fertility. These steps promote the development and maintenance of healthy, functional turf which has a competitive advantage against pests and also abiotic (non-living) sources of stress.

An IPM framework is applicable to all types of plant maintenance programs, and the primary objective of an IPM system for turf is to reduce the reliance on pesticides. User expectations and tolerance for damage are used to create action thresholds that dictate pest control measures. Management of pests is done on the basis of monitoring, evaluation, and knowledge of pest biology. Pesticides are used only when other approaches will not produce an acceptable level of turf quality and appearance. When properly implemented, the result is a cost effective maintenance program that minimizes the potential for adverse impact to the environment and human health. The product is vigorous, resilient turf that meets aesthetic and functional expectations.

Each section of this guide contains information pertinent to an effective, IPM-based turf maintenance program. Proper turfgrass selection, cultural management, monitoring techniques, accurate timing of materials applications, prudent selection of pest management materials, and environmental protection are covered. An IPM system for turf maintenance is most effectively implemented by an educated and experienced turf manager.

About the information in this guide

This publication is meant only to be a guide. The information herein is not presented as recommendations, but rather as research-based and expertly audited knowledge intended to help turf practitioners make informed decisions. The authors make no guarantees and assume no liability as to the efficacy of outlined practices or listed materials. The user of this information assumes all risks and liability for personal injury and property damage.

About pesticides referenced in this guide

Pest management guidelines assume a positive and accurate identification of the pest(s) in question.  For pest identification assistance please refer to the UMass Extension Plant Diagnostics Lab.

Pesticide materials are generally referred to by common (active ingredient) name in this guide. Where appropriate, common names are followed by trade or brand names in parentheses. Trade names are used for identification and reference purposes only. No product endorsement is indicated or implied, nor is discrimination intended against similar materials.

All pesticides listed in this publication are registered and approved for indicated uses according to the best available information at the time of publication. However, local, state and federal laws and regulations pertaining to pesticides vary and are subject to change. Pesticide applicators are advised to stay current with laws and regulations governing pesticides and their use.

In Massachusetts, applicators applying pesticides to the property of another or areas to which the public has access, both indoors and outdoors, must be licensed. It is the responsibility of the applicator to know and adhere to the licensing requirements of each state in which they work. See the Pesticide Regulations section of this guide for more information about pesticide use.

It is unlawful to use any pesticide in any manner other than the registered use. It is the responsibility of the applicator to verify the registration status of any pesticide for the intended use before applying it (refer to the Pesticide Resources page of this web site).

Some pesticides referred to herein may be classified “for restricted use only” in accordance with federal and/or state regulations. Persons purchasing and using “restricted use” pesticides must be licensed and certified applicators.

Read and follow the pesticide label
When using pesticides, applicators must read and strictly follow all directions on the pesticide label. The pesticide label is the law. In the event that pesticide label information is in conflict with information contained in this guide, the label shall take precedence.

 

Section 1: Integrated Pest Management for Turf

Background

Integrated Pest Management (IPM) is a systematic approach to problem solving and decision making for turf management. In practicing IPM, the turf manager utilizes information about the turf, pests, and environmental conditions in combination with targeted cultural practices. Pest populations and possible impact are monitored in accordance with a pre-determined management plan. Should monitoring indicate that action is justified, appropriate pest control measures are taken to prevent or control unacceptable turf damage. A sound IPM program has the potential to reduce the reliance on pesticides, because applications are made only when all other options to maintain the quality and integrity of the turf have been exhausted.

The key components of an IPM system for turf can be tailored to fit most management situations. The steps in developing a complete IPM program are as follows:

Assess site conditions and history

Determine and record site conditions, including current and past problems and potential future problems. The following should be included: a detailed site map including drainage and irrigation systems; a determination of functional condition and adequacy of drainage and irrigation systems; the age, condition, and species composition of the turf; the physical condition, texture, and variation of soils on the site; a current soil pH and nutrient analysis; the fertility history and a summary of the current fertility program; a pest history and current or potential problems. For information on how to obtain soil nutrient and physical analyses, refer to the UMass Soil and Plant Tissue Testing Lab at http://ag.umass.edu/services/soil-plant-nutrient-testing-laboratory or 413-545-2311.

Determine client or customer expectations

What is the intended use and expected quality of the turf? The answer to this question will help in making strategic decisions in regard to cultural and pest management options. In general, as the level of quality desired and the intensity of turf use increase, the required level of management attention and the need for inputs increase in turn.

Determine action thresholds

How much pest activity can be tolerated before action is necessary? This question will help to determine the response, or ‘action’, threshold. The action threshold is the point at which a pest population reaches a level capable of causing unacceptable damage to the turf.

The higher the level of turf quality desired, the lower the action threshold and the more likely it is that a turf manager will need to make a pesticide application to manage a problem pest. Appropriate threshold levels may vary considerably based on management goals and user expectations. The Nematode Management and Insect Management sections of this guide contain information on specific population threshold guidelines.

Establish a scouting and monitoring program

The purpose of scouting and monitoring is to gather information on pests and other problems (weather, environmental, cultural, soil, etc.) that are either currently compromising turf health and/or function or have the potential to do so at some point in the future. Monitoring refers to the regular, non-specific observation of a managed site, such as a quick visual scan conducted while mowing, for example. Scouting involves more focused observation with a specific goal in mind, as in determining the population of a problem pest or the cause of an area of thinning turf. Managed sites should be checked on a routine basis for pest presence, pest population density, and pest damage. Other potential problems (i.e. heat stress, excessive thatch accumulation, etc) should also be noted and recorded. Consult the appropriate pest sections of this guide for pest occurrence information useful in scouting disease, nematode, insect, and weed pests. Refer to the Turf Pest Damage Monitoring Chart (Appendix A) for approximations of when damage is most likely to occur.

Identify the pest/problem

What is the cause of the problem? Is it the result of a biological pest (disease, insect, weed), an environmental stress (heat, drought, shade), or a mechanical stress (scalping, aeration, traffic)? If an insect, disease, weed or nematode population affects a turf area, the turf manager must be knowledgeable about the life cycle of the problem pest. For example, when is damage most likely to occur? What is the most susceptible stage for control? In addition to this guide, many excellent references for the identification of insect, disease, and weed problems are available. Consult the References page of this web site for a list of suggested resources and references.

Implement a management decision

Prevention and control measures do not always involve the use of a pesticide. Proper cultural practices promote the health and viability of turfgrass, making the turf less susceptible to pest damage. Cultural management techniques as part of an IPM program should include: correct turf establishment procedures; the use of appropriate turfgrass species and cultivars; a carefully considered, site-specific fertility program; efficient irrigation; proper mowing height, equipment and frequency; traffic management procedures; and the use of supplementary practices such as aeration, topdressing, or overseeding when appropriate and necessary.

If a pest control measure is needed, the manager should consider the options available. Pesticides should be used only when other options and alternatives are not sufficient to manage the problem to the necessary extent. A material should be carefully selected based on its effectiveness, its potential to impact the environment, and the potential exposure to applicators and others. For example, if the site is adjacent to surface water (lakes, ponds, or streams) or has sandy soil in an area with a shallow water table, then mobile or persistent materials would be less appropriate to use than less mobile or less persistent materials.

Preventive pesticide applications should only be used within an established IPM plan. That includes scouting for pest activity regularly, providing the best agronomic conditions for the turf (minimizing stress), and keeping accurate records. However, if an area experiences pest damage each year (i.e. crabgrass, or white grubs), and scouting in previous years has confirmed the presence of damaging populations, then a preventive application may be appropriate. In select cases, preventive applications are preferable to curative applications owing to factors such as lower application rates, lower non-target toxicity, greater effectiveness, lower cost and/or existing application restrictions.

There are biological control options available for managing pest problems. Many of these alternatives (for example fungistatic bacteria, entomopathogenic nematodes, and growth regulators) are applied through traditional application equipment and handled like traditional materials, but may behave differently. When employing biological control options as part of an IPM program, the turf manager must know what to expect from these products and how to maximize their effectiveness.

Evaluate results and keep accurate records

The turf manager should determine if measures taken to manage a pest or alleviate a problem were truly effective in protecting and maintaining the quality and viability of the turf. These evaluations should be maintained as a key aspect of the written record.

As an essential component of a complete IPM program, records should contain all relevant information including, but not limited to: weather and environmental data such as humidity, precipitation, temperature (air and soil), soil pH, etc.; pest problems and pest “hot spots”; pesticide applications and results; timing, frequency, and effectiveness of cultural practices; fertilizer and other material applications; soil and tissue test results; and uncommon occurrences such as flood, prolonged ice cover, etc.

Communicate

Communication of findings, intentions, and actions to interested parties helps to make an Integrated Pest Management program complete. It is vital that lines of communication exist between supervisors, crew, and clients or customers. Effective communication will help to promote effective scouting and monitoring, and will enhance the success of management decisions and subsequent results.

Section 2: Turfgrass Selection - Species and Cultivars

Turfgrass species vary in terms of key attributes including appearance, appropriate uses, cultural requirements, pest resistance and stress tolerance. Individual cultivars (or varieties) within species provide additional options for effectively matching grasses with growing conditions, management level and desired performance. As such, the cultivars listed in this chapter exhibit above average turf forming properties compared to other cultivars.

Turfgrass selection decisions are among the most important that a turf manager makes, as poorly adapted species and cultivars are major causes of turf deterioration. Grasses well-matched to the growing environment require less input in terms of water, fertilizer, and management attention, and are far more likely to perform as intended and exhibit desired aesthetic characteristics.

Selection of adapted turfgrass species and cultivars is a fundamental exercise in any IPM program for turf. Adapted grasses are more resistant to stress and pest pressure and are therefore instrumental in reducing pesticide use to the lowest possible level.

How to use this section

The following are some commercially available turfgrass cultivars (varieties) which have performed well in Massachusetts or nationally based on National Turfgrass Evaluation Program (NTEP) tests. Please note that this is not an exhaustive list and there may be other reliable cultivars not evaluated by NTEP, or experimental cultivars that are not yet commercially available, that also perform well. For additional information visit the NTEP web site at http://www.ntep.org.

It is important to note that seed mixtures and blends are strongly preferred to monostands (planting of only one species and/or cultivar), as they produce a turf that works more effectively as a system.

  • A seed mixture is a combination of multiple, different turfgrass species.
  • A seed blend is a combination of multiple, different turfgrass cultivars within the same species. Therefore, a seed mixture can and often does include multiple blends.

When mixing and blending turfgrass species and cultivars, first consider the characteristics and adaptations of the individual turfgrass species and the site conditions such as soil type, cultural intensity and intensity of use, shade, and desired quality of the turf. It is also important to consider any past history of repeated damage from pests such as disease and insects.

First, select the best adapted species (Table 1) and mixture (Table 2) for the growing conditions and specific use, then select 2 or 3 cultivars within each species component from the preferred list for Massachusetts (Tables 3 to 8) that provide the best tolerance to commonly occurring diseases and other stresses.

Remember that regardless of careful turfgrass selection, the level of turf quality ultimately depends on the quality of management.


With regard to disease tolerance of individual cultivars, please note that the occurrence of favorable climatic conditions for disease varies from year to year. Disease ratings should be used to a) identify particularly susceptible cultivars that should be avoided in disease prone areas, or b) to choose disease tolerant cultivars for reseeding or overseeding an area previously damaged by disease. Proper cultural practices intended to reduce disease incidence are critical for cultivars to fully demonstrate disease tolerance. Disease may occur even in tolerant cultivars following exposure to favorable climatic conditions or improper cultural practices that promote disease.

Table 1. General characteristics of some major cool-season turfgrass species.

Characteristic Kentucky bluegrass Perennial ryegrass Creeping bentgrass Tall fescue Fine fescues
Growth habit rhizomatous bunch-type stoloniferous bunch various
Texture (leaf width) medium-fine to medium medium-fine to medium fine medium to coarse very fine
Soil type preferred well drained, moist, fertile moist, fertile well-drained, moist, fertile moist, fertile infertile, well drained
Tolerance to:          
Cold good poor to fair excellent fair good
Heat fair poor to fair fair to good excellent poor to fair
Drought good good poor excellent excellent
Salinity poor fair excellent good poor
Submersion fair fair excellent good poor
Wear fair excellent fair to good excellent poor
Compaction fair to good excellent fair to good fair poor
Shade poor poor fair to good fair to good excellent
Establishment slow fast medium medium to fast medium to fast
Recovery from injury excellent poor excellent poor poor *
Disease potential medium medium high low low to medium
Cultural requirements:          
Fertility medium to medium-high medium to medium-high high medium to medium-high low
Mowing Frequency low to medium high high medium-high low
Thatch potential medium low high low medium
* The capacity of creeping red fescues to recover from injury is considered fair due to rhizomatous growth habit.


Table 2. Guidelines for mixing and blending cool-season grasses for specific applications. The following are some general guidelines for effective mixtures and blends of cool-season turfgrasses for the Northeast. Read the appropriate row for the target use from left to right to determine the species percentages by weight and the suggested seeding rate range for each mixture. Refer to the footnotes for recommended blending parameters for varieties within species. Other mixture or blend options may exist based upon expectations and specific site and use conditions.

Use Turfgrass Species (% by weight) Seeding rate (lbs/1000ft2)
Kentucky bluegrass perennial ryegrass 1 fine fescues tall fescue 2 rough bluegrass creeping bentgrass
Athletic fields (new fields) 80% * 20% *         3 to 4
Athletic fields (new fields) 100% *           1 to 2
Athletic fields (overseeding key wear areas)   100% *         6 to 8 3
Golf course (putting greens)           100% ** 0.5 to 1
Golf course (fairways and tees)           100% * 0.5 to 1
Lawns - sun (med to high maintenance) 65-75% * 10-20% * 15% **       3 to 4
Lawns - sun (med to high maintenance) 20% *     80% *     6 to 8
Lawns - sun (med to high maintenance)   20% *   80% *     7 to 9
Lawns - sun (low maintenance) 5-25% * 10-20% * 65-75% *       4 to 6
Lawns - more sun than shade (well drained) 4 ≤15% *5 ≤15% *5 ≥70% *       4 to 6
Lawns - more shade than sun (well drained)   10-20% *5 80-90% *       4 to 6
Lawns - shade (wet) 30% *5       70% **6   2 to 3

* Two to three improved cultivars recommended
**One or more improved cultivars recommended
1 Perennial ryegrass content in mixes should not exceed 20% due to aggressive seedling growth.
2 Tall fescue is more readily adaptable to certain areas of New England, particularly the southern coastal areas.
3 Suggested rate when more than 50% of the area is bare soil.
4Use a minimum of 70% fine fescues and split the remainder with Kentucky bluegrass and perennial ryegrass.
5 Select cultivars with improved shade tolerance for use on shaded sites whenever possible.
6 Use of rough bluegrass should be considered carefully because of the potential to become an undesirable weed.

SOIL TESTS
Soil samples should be taken at least four to six weeks before establishment of turf to allow sufficient time to fertilize and/or adjust pH based on soil test results. Take samples before fertilizing, or no sooner than four weeks after. To submit a representative sample, take about 12 samples, 4”-6” deep. Remove stones and debris, and do not include thatch. Mix all samples together, and spread the soil out on a clean surface to air dry. A one-cup measure of the mixture is all that is required for a soil test. For instructions on how to submit your sample, as well as information on available tests and fee structure, visit the UMass Soil Testing Lab at ag.umass.edu/services/soil-plant-nutrient-testing-laboratory. For information about plant problem diagnostics, refer to the UMass Extension Plant Diagnostic Lab at ag.umass.edu/services/plant-diagnostics-laboratory.

KEY. Coding used to indicate disease and stress tolerances in Tables 3 through 8 for cultivars recommended for Massachusetts.

Un-shaded columns represent desirable traits; in these columns a ‘+’ denotes a positive effect and a ‘–‘ denotes a negative effect. For example, a ‘+’ in the ‘Anthracnose’ column indicates superior anthracnose tolerance, while a ‘-‘ in the ‘Wear Tolerance’ column indicates inferior tolerance to wear. Shaded columns represent undesirable traits; in these columns an ‘M’ denotes a negative effect and an ‘L’ denotes a positive effect. For example, an ‘M’ in the ‘Scalping Injury’ column indicates a cultivar more prone to scalping injury, while an ‘L’ in the ‘Seedhead Tendency’ column indicates a cultivar less likely to produce seedheads.
Code Code
+ Significantly above average H High tendency for undesirable trait
- Significantly below average L Low tendency for undesirable trait
0 Average M Average
A blank cell indicates that there is no data available for a given species for the subject trait.


Table 3. Relative disease and stress tolerances for some commercially available bentgrass cultivars recommended for golf greens in Massachusetts.

Cultivar Species Anthracnose Brown patch Dollar spot Typhula (snow mold) Leaf spot Cutworm tolerance Green color Wear tolerance Scalping injury Thatch tendency
13-M Creeping 0 0 0 0 0 + - - L L
Authority Creeping + - 0   - 0 0 0 M M
Barracuda Creeping 0 0 +   + + 0 0 H M
Declaration Creeping + 0 + 0 + + - - H M
Greenwich Velvet - + + + + - + + H H
L-93 Creeping 0 - 0   + 0 0 - L L
Legendary Velvet 0 + + + + - + + H H
LS-44 Creeping + 0 0 0 0 + - - H L
Luminary Creeping 0 + 0   + 0 0 + L H
Memorial Creeping + - - - 0 + - - L L
Penn A-1 Creeping 0 - -   0 - 0 0 M M
Penn A-2 Creeping + - 0   + + 0 - M M
Pure Distinction Creeping + + -   - + - + L H
Proclamation Creeping 0 0 0   0 0 0 0 H M
T-1 Creeping + - - - 0 + 0 0 L H
Venus Velvet 0 + + + + - + + H M
Vesper Velvet 0 + + + + - + + H H
Villa Velvet + + + + + - + + H H


Table 4. Relative disease and stress tolerances for some commercially available bentgrass cultivars recommended for golf fairways in Massachusetts.

Cultivar Species Anthracnose Brown patch Dollar spot Typhula (snow mold) Drought tolerance Green color Wear Tolerance Poa ingress Scalping injury Thatch tendency
13-M Creeping - + 0 0 + +   L    
007 Creeping + + 0 - 0 0 - L H H
Authority Creeping - + 0 + + 0 + L L H
Barracuda Creeping 0 + +   - 0 - L H H
Bengal Colonial - + 0 0 + +   L    
Crystal Bluelinks Creeping 0 + 0 - + + + M L L
Declaration Creeping - + + 0 + + - L H L
Greentime Colonial - 0 0 - + - 0 H L M
Independence Creeping - + - + 0 +   L    
Kingpin Creeping - + 0 + 0 +   L    
L-93 Creeping - + - 0 0 0 0 M M H
Luminary Creeping 0 + 0 + - 0 + M L H
Mackenzie Creeping - + 0 + - +   L    
Memorial Creeping + + 0 0 - 0 + L L M
Penncross Creeping - + - - 0 0 0 M L L
Penneagle II Creeping 0 + 0 0 + 0   L    
Princeville Creeping - + - - 0 - - H L L
Proclamation Creeping - + 0 0 + 0 - L H M
Pure Select Creeping - + - - 0 0 0 M M M
Shark Creeping 0 + - + 0 0   L    
T-1 Creeping 0 + 0 0 + + + M L M
Tiger II Colonial 0 - + + 0 - 0 H L L


Table 5. Relative disease and stress tolerances for some commercially available fine leaf fescue cultivars recommended for Massachusetts.

Cultivar Species Brown patch Dollar spot Pink patch Pythium blight Red thread Drought tolerance Green color Mowing injury Poa ingress
Chantilly Creeping 0 + - 0 0 0 0 H M
Fairmont Chewings + + 0 - 0 0 + H L
Intrigue 2 Chewings 0 + 0 0 0 0 - M L
Longfellow 3 Chewings + + - - 0 0 0 M L
Navigator II Creeping 0 - 0 + - + + H H
Radar Chewings + + + - 0 + + H L
Rosecity Creeping - - - 0 - - 0 H H
Treasure II Chewings 0 + - 0 0 0 - L L
Wrigley 2 Chewings 0 0 0 - 0 0 - M L
Zodiac Chewings + + 0 - 0 0 0 L L


Table 6. Relative disease and stress tolerances for some commercially available tall fescue cultivars recommended for Massachusetts.

Cultivar Brown patch Red thread Leaf rust Typhula (Snow mold) Drought tolerance Green color Leaf width
Bullseye + + 0 0 + 0 0
Cannavaro - 0 + 0 - 0 -
Catalyst 0 + + - + - 0
Cochise IV + + + 0 0 0 -
Essential - + + + 0 0 0
Faith + + + 0 0 + -
Falcon V 0 + + - + 0 -
Finelawn Xpress - 0 0 0 - 0 0
Firecracker LS 0 + - - 0 0 -
Garrison 0 + + 0 0 + 0
Greenbrooks 0 0 0 - 0 0 0
Hemi + 0 - 0 0 0 0
Jamboree 0 0 0 - 0 0 -
LS 1200 0 0 0 - 0 + 0
Monet 0 0 + - 0 0 0
Mustang 4 + 0 + - + 0 0
Rhambler SRP 0 + 0 - 0 0 0
Shenandoah Elite + 0 + 0 - 0 -
Shenandoah III 0 + - - 0 0 0
Speedway 0 0 0 0 0 0 0
Spyder LS - - 0 0 0 + 0
Tanzania + 0 - 0 + + 0
Traverse SRP + 0 + - 0 0 0
Turbo + 0 0 0 0 0 0
Van Gogh 0 0 - - + 0 0
Wolfpack II + + 0 - + 0 0


Table 7. Relative disease and stress tolerances for some commercially available Kentucky bluegrass cultivars recommended for Massachusetts.

Cultivar Dollar spot Leaf spot Summer patch Drought tolerance Green color Mowing quality Seedhead tendency Thatch tendency
Arrowhead 0 - 0 0 + - + +
Award + 0 - 0 + 0 0 -
Barvette HGT 0 0 + 0 - + - -
Blue Coat + 0 0 0 + - + -
Blue Note + 0 + 0 0 0 0  
Bluebank + 0     +     -
Cabernet 0 + + 0 0 0 0 -
Dauntless 0 + - - - 0 0 -
Empire + 0 0 0 + + - 0
Endurance + + 0 + + - + -
Keeneland 0 + 0 + + 0 0 +
Legend + 0 0 + + - + -
Mazama   +     +     -
Merlot   +     +     -
Midnight + 0 + - + + - -
Nu Chicago + 0 0 0 + + - -
Oasis + + 0 + + - + -
Rubix 0 0 - 0 0 0 0 -
Rush 0 0 - - + + - -
Skye + 0 + + 0 0 0 -
SRX 2758 0 + 0 - + + - -
SRX 4338 0 + 0 0 0 0 0 0
SRX 466 + + + - 0 + - -
SRX 5321 + 0 0 + - - + -
Sudden Impact + 0 0 0 + + - -


Table 8. Relative disease and stress tolerances for some commercially available perennial ryegrass cultivars recommended for Massachusetts.

Cultivar Brown patch Leaf Rust Red thread Pythium blight Green color Mowing quality Poa ingress Seedhead tendency Wear tolerance
Amazing 0 + 0 - 0 0 - 0 +
Bandalore + 0 + - 0 0 - 0 +
Banfield + + 0 - 0 - - - 0
Benchmark + 0 + - 0 0 - 0 +
Diligent + + + - 0 0 - 0 +
Evolution 0 + 0 - 0 0 - + 0
Grand Slam GLD + + + 0 0 0 - - 0
Green Supreme 0 + + 0 0 0 - 0 +
Karma + + + - 0 + - - -
Monsieur + +   - 0 0 - + +
Palmer V 0 + 0 - 0 0 - 0 +
Pangea GLR + + 0 - + - - 0 0
Pizzazz 2 + + + - 0 0 0 0 0
Premium 0 + 0 - 0 0 - + 0
Rinovo + + 0 - 0 0 - - 0
Rio Vista 0 + 0 - 0 0 - 0 -
Sideways 0 + + - 0 0 - + 0
SR 4650 + + - - 0 0 - 0 0
Stamina + + + - 0 + - 0 +
Thrive + + 0 - + + - - 0
Vision + + 0 - 0 - - + 0
Wicked + 0 + - 0 + - 0 +

Section 3: Weed Management

In this section:

Understanding weed life cycles

A weed is defined as a plant out of place, or a plant growing where it is not desired. Weeds compete with turfgrasses for light, water, soil nutrients and space. In a turf, weeds disrupt uniformity and are often considered to be aesthetically unpleasing. With a few exceptions, weeds will not provide year-round vegetative cover. A year-round turf cover is especially beneficial to prevent erosion and runoff, and in areas that might receive moderate to heavy use during the non-growing season. Weeds in athletic fields can adversely affect playability and athlete safety.

Weeds of turf are most often categorized by their life cycle. The most important thing one can learn about a specific weed is its life cycle. Knowledge of the life cycle is valuable when attempting to manage a specific weed because not all strategies are appropriate for all life cycles. Also, the timing of when a specific control strategy is implemented will vary based on a weed’s life cycle. A weed can be a summer annual, winter annual, biennial or perennial (Tables 9 and 10).

Annual weeds

Annual weeds reproduce by seed and complete their life cycle in one year. The annual life cycle is further divided into summer annual weeds and winter annual weeds. Summer annual weeds germinate in spring or early summer, grow vegetatively, flower and produce seed and die in late summer or fall. Examples of summer annual weeds include crabgrass, yellow foxtail, goosegrass, barnyardgrass, ragweed, purslane, spotted spurge, pigweed, carpetweed and prostrate knotweed. Winter annual weeds germinate in late summer and fall. They grow vegetatively and go dormant with the arrival of cold weather. In the spring they continue to grow vegetatively early and then switch to a reproductive phrase during which they flower and produce seed. After flowering, they die with the onset of warm weather. Winter annual weeds can be just as problematic and troublesome as summer annual weeds. Examples of winter annual weeds include shepherd’s-purse, common chickweed, sticky chickweed, annual bluegrass, henbit, pineappleweed, spring whitlowgrass and corn speedwell.

Biennial weeds

Biennial weeds reproduce by seed and complete their life cycle in two years. Biennial weeds germinate in spring to early summer and grow vegetatively forming a leaf rosette at the end of the first growing season. After over-wintering as a rosette, the biennial weed resumes growth, flowers, produces seed and completes the life cycle in the second growing season. Examples of biennial weeds are common mullein, burdock, bull thistle, wild carrot and garlic mustard.

Perennial weeds

Perennial weeds live for three or more years and reproduce by seed and vegetative propagules including roots, rhizomes, stolons, tubers, and bulbs. Dandelion, broadleaf plantain, narrowleaf plantain, broadleaf dock, false dandelion, spotted cat’s ear and fall dandelion are examples of simple perennials and reproduce by seed. Spreading perennials reproduce by seed and vegetative propagules and can form sizable clonal patches in turf. Examples of spreading perennials are quackgrass, red sorrel, creeping woodsorrel, Canada thistle and ground ivy. Other perennials such as wild garlic and star-of-bethlehem arise from bulbs. Yellow nutsedge arises from small tubers called nutlets.

Table 9. Life cycles of common broadleaf turf weeds

Common name Scientific name Life cycle
alyssum, hoary Berteroa incana perennial
bedstraw, catchweed Galium aparine winter annual
bedstraw, smooth Galium mollugo perennial
beggarticks, devil’s Bidens frondosa summer annual
bittercress Cardamine hirsuta winter annual
bittercress, cuckoo Cardamine pratensis perennial
bluets Houstonia caerulea perennial
buttercup, bulbous Ranunculus bulbosus perennial
buttercup, creeping Ranunculus repens perennial
carpetweed Mollugo verticillata summer annual
carrot, wild Daucus carota perennial
cat’s ear Hypochaeris radicata perennial
celandine, lesser Ranunculus ficaria perennial
chickweed, common Stellaria media winter annual
chickweed, mouse-ear Cerastium vulgatum perennial
chickweed, sticky Cerastium viscosum winter annual
chicory Cichorium intybus perennial
cinquefoil, old field Potentilla simplex perennial
cinquefoil, silvery Potentilla argentea perennial
clearweed Pilea pumila summer annual
clover, alsike Trifolium hybridum perennial
clover, rabbitfoot Trifolium arvense summer annual
clover, red Trifolium pratense perennial
clover, white Trifolium repens perennial
common lambsquarters Chenopodium album summer annual
copper-leaf, rhombic Acalypha rhomboidea summer annual
daisy, oxeye Chrysanthemum leucanthemum perennial
dandelion Taraxacum officinale perennial
dandelion, fall Leontodon autumnalis perennial
deadnettle, red Lamium purpureum winter annual
deptford pink Dianthus armeria perennial
dock, broadleaf Rumex obtusifolius perennial
dock, curly Rumex crispus perennial
evening primrose, common Oenothera biennis biennial
fleabane, annual Erigeron annuus winter annual/biennial
fleabane, poor-robin Erigeron pulchellus perennial
galinsoga, hairy Galinsoga ciliata summer annual
garlic, wild Allium vineale perennial
ground ivy Glechoma hederacea perennial
groundsel, common Senecio vulgaris summer annual
hawksbeard, narrowleaf Crepis tectorum summer annual
hawkweed, orange Hieracium aurantiacum perennial
hawkweed, yellow Hieracium pretense perennial
healall Prunella vulgaris perennial
hedge bindweed Calystegia sepium perennial
henbit Lamium amplexicaule winter annual
horseweed Conyza canadensis winter annual
jimsonweed Datura stramonium summer annual
knawel Scleranthus annuus winter annual
knotweed, prostrate Polygonum aviculare summer annual
maiden pink Dianthus deltoids perennial
mallow, common Malva neglecta annual/biennial
medic, black Medicago lupulina annual
moneywort Lysimachia nummularia perennial
mouse-ear cress Arabidopsis thaliana winter annual
mugwort Artemisia vulgaris perennial
nightshade, eastern black Solanum ptycanthum summer annual
pearlwort, birdseye Sagina procumbens perennial
pepperweed, virginia Lepidium virginicum summer or winter annual
pigweed, prostrate Amaranthus lividus summer annual
pigweed, redroot Amaranthus retroflexus summer annual
pimpernel, scarlet Anagallis arvensis summer annual
pineappleweed Matricaria matricariodes winter annual
plantain, broadleaf Plantago major perennial
plantain, narrowleaf Plantago lanceolata perennial
pokeweed, common Phytolacca americana perennial
purslane, common Portulaca oleracea summer annual
pussytoes, field Antennaria neglecta perennial
ragweed, common Ambrosia artemisiifolia summer annual
ragweed, giant Ambrosia trifida summer annual
rocket, yellow Barbarea vulgaris biennial
sandspurry, red Spergularia rubra summer annual
shepherd’s-purse Capsella bursa-pastoris winter annual
smartweed, ladysthumb Polygonum persicaria summer annual
smartweed, Pennsylvania Polygonum pensylvanicum summer annual
sorrel, red/sheep Rumex acetosella perennial
sowthistle, annual Sonchus oleraceus summer annual
sowthistle, perennial Sonchus arvensis perennial
sowthistle, spiny Sonchus asper summer annual
speedwell, common Veronica officinalis perennial
speedwell, corn Veronica arvensis winter annual
speedwell, purslane Veronica peregrina winter annual
speedwell, thymeleaf Veronica serpyllifolia perennial
spurge, spotted Euphorbia maculata summer annual
star-of-bethlehem Ornithogalum umbellatum perennial
stitchwort Stellaria graminea perennial
strawberry, wild Fragaria virginiana perennial
thistle, Canada Cirsium arvense perennial
thymeleaf sandwort Arenaria serpyllifolia winter annual
toadflax, oldfield Linaria canadensis summer annual
toadflax, yellow Linaria vulgaris perennial
tower mustard Arabis glabra biennial
trefoil, birdsfoot Lotus corniculatus perennial
velvetleaf Abutilon theophrasti summer annual
violet, wild Viola spp. perennial
white cockle Silene alba perennial
whitlowgrass, spring Draba verna winter annual
woodsorrel, creeping Oxalis corniculata perennial
yarrow Achillea millefolium perennial
yellow woodsorrel Oxalis stricta perennial

Table 10. Life cycles of common grass and grass-like turf weeds

Common name Scientific name Life cycle
barnyardgrass Echinochloa crus-galli summer annual
bentgrass, creeping Agrostis stolonifera perennial
bluegrass roughstalk Poa trivialis perennial
bluegrass, annual Poa annua winter annual/perennial
bluegrass, bulbous Poa bulbosa perennial
brome, downy Bromus tectorum winter annual
crabgrass, smooth or small Digitaria ischaemum summer annual
crabgrass, large or hairy Digitaria sanguinalis summer annual
fescue, tall Festuca arundinacea perennial
foxtail, giant Setaria faberi summer annual
foxtail, yellow Setaria glauca summer annual
goosegrass Eleusine indica summer annual
lovegrass, purple Eragrotis spectabilis perennial
nimblewill Muhlenbergia schreberi perennial
nutsedge, yellow Cyperus esculentus perennial
orchardgrass Dactylis glomerata perennial
panicum, fall Panicum dichotomiflorum summer annual
paspalum Paspalum setaceum perennial
quackgrass Elytrigia repens summer annual
rush, path Juncus tenuis perennial
sandbur, longspine Cenchrus longispinus summer annual
stiltgrass, Japanese Microstegium vimineum summer annual
stinkgrass (lovegrass) Eragrostis cilianensis summer annual
timothy Phleum pratense perennial
witchgrass Panicum capillare summer annual
zoysiagrass Zoysia japonica perennial

 

Scouting for turf weeds

Scouting and monitoring are important components of an effective integrated management program for turf weeds. Monitoring should be done every time a turf manager is on a particular site, in addition to an all-inclusive, in-depth scouting event carried out in late summer or early fall.

The turf manager should use a back and forth or zig-zag pattern when scouting for weeds, being sure to cover all distinctly different and/or known problem areas. Special attention should be given to areas of thin turf and possible causes, as well as newly introduced weeds and historically problematic weeds that are not controlled with the current management program. All weed species present and their respective life cycles should be recorded. Observations can be recorded on a site map or listed on a sheet with location identified. Regular scouting and accurate weed identification enables a turf manager to plan and implement an appropriate management approach and to evaluate the long-term effectiveness of control strategies.

Indicator weeds

There is an old adage that states “Weeds are the result of a poor turf, not the cause of a poor turf”. Weed infestation often suggests that there are one or more underlying factors contributing to poor turf health and vigor. A comprehensive list of all weeds should be developed as a turf manager scouts a specific turf site; however there are certain weed species that should be scrutinized more carefully. These weed species, often referred to as “indicator weeds” or “diagnostic weeds”, are particularly competitive when environmental conditions are not optimal for turfgrass growth. The occurrence of indicator weeds can be used as a starting point in identifying those factors that may contribute to poor turf. Identifying and correcting those factors can tip the competitive balance in favor of the turfgrass while minimizing, and in some cases eliminating, many weed infestations.

Red sorrel and bluets are common inhabitants of acid soils, whereas broadleaf plantain may be more abundant at high soil pH. Crabgrass and many other annual weeds require light for germination and thrive in turf areas that are thin as a result of low fertility. White clover and birdsfoot trefoil are also common in low fertility situations and may indicate the need for fertilization. Prostrate knotweed, goosegrass, pineappleweed and path rush commonly occur where the soil has become compacted. Excessive irrigation and/or poorly drained soils may result in an increase in the occurrence of algae, moss, annual bluegrass, creeping bentgrass and yellow nutsedge. Some weeds such as ground ivy, common speedwell and moss are able to thrive in shaded conditions.

Turf managers should not assume that just because these weeds are present that a specific problem exists. For example, red sorrel can grow at high pH and ground ivy may persist in turf areas that receive full sun. While the use of “indicator weeds” is not a fool proof method, it can be a valuable tool in the assessment of potential problems at a turf site.

Cultural practices for weed management

Cultural practices are a vital component within an effective management program for turf weeds. Successfully executed cultural practices can result in a healthier, denser turf which increases the overall competitive nature of the stand and decreases the severity of many weed infestations. Some weed infestations can be significantly reduced or even eliminated with the use of appropriate and well-timed cultural practices.

Mowing

Many weeds require light for germination and establishment. Increasing the mowing height within the range for the particular species or mix of species present will result in a decrease in the amount of light reaching the soil surface and can reduce weed germination and establishment. This is particularly important in the spring and early summer during the peak germination period of annual grassy weeds. Decreasing the height of cut and collecting clippings that contain seedheads during the late summer and early fall can be effective in reducing the amount of viable seed that is added to the weed seed bank.

Fertility

Fertility, as with mowing height, can play a major role in the reducing the amount of light that penetrates the turf canopy and reaches the soil surface. Fertilization programs should supply adequate and balanced nutrition to yield a dense turf. Avoid high levels of fertility during the summer months when cool-season turfgrasses are less competitive. If heavy summer weed pressure has thinned turf, an application of fertilizer in late summer or early fall will support turf recovery. Fertilization after herbicide applications can aid in the filling of canopy voids left by dying weeds.

Aeration

Compaction is a major contributor to thin turf and the encroachment of weeds. An effective aeration program will alleviate compaction and increase overall turf health and density. However, aeration methods that bring soil to the surface can reposition weed seeds, which were once too deep to germinate, to a location where germination and establishment are favored. The alleviation of compaction in conjunction with overseeding of desirable grasses can reduce and in some cases eliminate weeds such as goosegrass, pathrush, pineappleweed and prostrate knotweed.

Irrigation

Many annual weeds, including crabgrass, are warm-season species. Warm-season species are capable of growing very well during the hot, dry periods characteristic of summer. Turfgrass species utilized in the northeast are cool-season species and, without adequate moisture from rainfall or irrigation, become dormant during the summer. During periods when the growth of cool-season turfgrass species has slowed or ceased as a result of low soil moisture and high temperatures, warm-season annual weeds become very competitive in otherwise healthy, dense turf. If some weed encroachment is not acceptable, irrigation should be applied in the absence of summer rainfall to maintain turf growth and prevent summer dormancy. Special attention should be focused on areas that are prone to drought including elevated areas, south and southwest facing slopes and areas adjacent to hardscapes such as sidewalks and driveways. If there is annual weed pressure and the turf at a site is going to be allowed to go dormant during the summer months, the option also exists to apply a preemergence herbicide in the spring. If turf has thinned due to drought dormancy, overseeding with desirable turfgrass species should be done in late summer/early fall when cooler temperatures and rainfall return.

The over-watering of turf areas can also contribute to weed encroachment. Weeds such as annual bluegrass, creeping bentgrass, and yellow nutsedge can be more problematic on over-irrigated sites. On poorly-drained sites, the installation of a drainage system may be warranted to decrease naturally-existing excessive soil moisture.

Turf Renovation and Establishment

Turf renovation and establishment projects carried out in the spring and early summer without the use of a preemergence herbicide fail more often than not due to annual weed pressure. Summer annual weed pressure is minimal when turf renovation and establishment is initiated in the late summer and early fall. Warm-season annual weeds that germinate later in the season seldom reach a size that deters turf establishment and die with the onset of cold weather. Special attention should be paid to winter annual weed encroachment in such areas, however.

When planning a turf renovation, choose turfgrass species and cultivars that are best suited for the site conditions and expected turf use. Aggressive cultivars should be considered when available. Encourage rapid establishment by providing adequate fertility at seeding. Maintain good soil moisture during the germination and early establishment period. Overseeding can be a valuable tool in restoring sites where turf thinning has resulted from insufficient annual weed control. Openings in the turf as a result of insect damage, diseases and excessive wear are prone to weed encroachment. Overseeding is frequently useful to repair such damage and regain turf density.

Characteristics of turf herbicides

In turf management, the two most basic categories of herbicides are preemergence and postemergence. Preemergence materials are applied preventively, that is prior to germination, to control weeds that have not yet appeared. Postemergence materials are applied to existing, actively growing weeds.  Some herbicides have both preemergence and postemergence activity. With such materials, appropriate application timing can be dictated by the target weed(s), distinct characteristics of the herbicide, or specific management goals.

Herbicides can be more finely categorized into chemical classes, which indicate the mode or mechanism of action of each compound. The particular mode of action influences whether a material is effective against broadleaf weeds, grassy weeds, or a more specific collection of species. Many individual modes of action offer selective control of weeds within desirable turf, while others provide non-selective control more appropriate for spot treatment and renovation situations.

Refer to Table 12 below to cross reference trade names with active ingredients.

Table 11. Characteristics of turf herbicide active ingredients registered for use in Massachusetts.

amicarbazone

Chemical class Mode of action Application timing
triaolinone inhibits photosynthesis postemergence

Controls annual bluegrass, crabgrass, bittercress, carpetweed, henbit, field pennycress, common chickweed, sticky chickweed, Virgina pepperweed, purslane, shepherd’s-purse, spurge, and oldfield toadflax.

benefin

Chemical class Mode of action Application timing
dinitroaniline interferes with cell division preemergence

Controls crabgrass, goosegrass, annual bluegrass, yellow foxtail and many annual broadleaf weeds.

bensulide

Chemical class Mode of action Application timing
organophosphate interferes with cell division and inhibits rooting. preemergence

Controls annual bluegrass, crabgrass, goosegrass, henbit, lambsquarters, and yellow foxtail. Provides excellent control of annual bluegrass. Strongly adsorbed to soil, potential for leaching is very low.

bentazon

Chemical class Mode of action Application timing
benzothiadiazole inhibits photosynthesis, causes cell membrane destruction postemergence

Controls primarily yellow nutsedge; will provide control of broadleaf weeds including Canada thistle, groundsel, ladysthumb, lambquarters, Pennsylvania smartweed, purslane, shepard’s purse and yellow woodsorrel.

Controls primarily yellow nutsedge; will provide control of broadleaf weeds including Canada thistle, groundsel, ladysthumb, lambquarters, Pennsylvania smartweed, purslane, shepard’s purse and yellow woodsorrel.

Contact herbicide. Some temporary turf discoloration may occur. The addition of a surfactant is required for application. Bentazon is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.

bispyribac-sodium

Chemical class Mode of action Application timing
pyrimidinyloxybenoic inhibition of amino acid synthesis postemergence

Controls annual bluegrass and roughstalk bluegrass in creeping bentgrass and perennial ryegrass, also broadleaf plantain, common chickweed, dandelion, henbit, narrowleaf plantain, white clover and yellow woodsorrel.

May injure Kentucky bluegrass, especially some cultivars. Labeled for use only on golf courses and sod fields.

carfentrazone

Chemical class Mode of action Application timing
protox inhibitor inhibits chlorophyll production, results in rapid destruction of cell membranes postemergence

Controls a wide range of broadleaf weeds.

Often formulated in pre-mixed combinations with other broadleaf herbicides. Does not provide good control of perennial broadleaves when applied alone. Provides good moss control. Does not persist in soil and has no leaching potential.

chlorsulfuron

Chemical class Mode of action Application timing
sulfonylurea inhibition of amino acid synthesis postemergence

Controls tall fescue, annual ryegrass and perennial ryegrass in Kentucky bluegrass, fine fescue and bentgrass; also buttercup, cinquefoil, common chickweed, common mallow, henbit, mouse-ear chickweed, pineappleweed, prostrate knotweed, purslane, shepards-purse, white clover, wild garlic and wild violet.

clopyralid

Chemical class Mode of action Application timing
pyridine disrupts growth by mimicking naturally occurring plant hormones. postemergence

Broad spectrum; controls many broadleaves, particularly effective on members of the aster family (dandelion and hawkweed) and bean family (clover, black medic and birdsfoot trefoil). Translocated within the plant.

Herbicide products that contain clopyralid are Restricted Use on residential turf. Turf clippings from treated areas should not be collected for mulching and composting or sent to a recycling facility. Use caution near ornamentals, including aster, daisy, coneflower, liatris, redbud, and honeylocust. Clopyralid is weakly adsorbed to soil and has a moderate leaching potential.

corn gluten meal

Chemical class Mode of action Application timing
not classified inhibition of root growth at germination. preemergence

Labeled for the control of crabgrass species.

Corn gluten meal is a by-product of the wet-milling of corn grain for the production of corn starch and corn syrup. Because of its high protein content (about 60% by weight), its historic use has been as an animal feed. Its associated nitrogen concentration of about 9 to 10% N makes it a fertilizer. The carrier of the nitrogen is the proteinaceous fraction of the corn grain; several dipeptides in this fraction comprise the active ingredient that imparts some preemergence herbicidal activity. Research suggests that the herbicidal activity is greater in dry environments than in areas where soil moisture for plant growth is adequate. Product application rates for turf are 10 to 20 lbs of corn gluten meal per 1000 ft2 applied twice a year (equal to approximately 2 to 4 lbs of N per 1000 ft2 per year) with some products suggesting higher rates. Studies conducted at the University of Massachusetts indicate that crabgrass control using corn gluten provided no advantage over maintaining a properly fertilized lawn regardless of whether the fertilizer material used was organic or synthetic. Corn gluten is considered to be organic.

dicamba

Chemical class Mode of action Application timing
benzoic acid disrupts growth by mimicking naturally occurring plant hormones. postemergence

Controls many broadleaf weeds, especially red sorrel, dandelion, violets, plantains, chickweed, ground ivy, buttercup and woodsorrel.

Formulated alone and in premixed combinations with other broadleaf herbicides. Susceptible weeds curl and twist soon after application. Drift to desirable plants, particularly flowers, ornamentals, and other broadleaf plants should be prevented. Dicamba leaches readily into the soil and is soil active, therefore applications within the drip line of trees should be avoided.

dimethenamid

Chemical class Mode of action Application timing
chloroacetanilide/chloroacetamide inhibits very long chain fatty acid synthesis preemergence

Controls annual bluegrass, crabgrass, downy brome, yellow foxtail, fall panicum, sandbur, bittercress, carpetweed, lambsquarters, pigweed, puslane, common ragweed, shepherd’s-purse, spurge, willowherb, kyllinga and yellow nutsedge.

Dimethenamid is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.

dithiopyr

Chemical class Mode of action Application timing
pyridine inhibits cell division. preemergence

Controls annual grasses, including annual bluegrass, barnyardgrass, crabgrass, downy brome, yellow foxtail and sandbur. Also provides preemergence control of several broadleaf weeds including bittercress, carpetweed, henbit, black medic, pineappleweed, purslane, shepard’s-purse, corn speedwell, spurge, yellow woodsorrel and creeping woodsorrel. Enters the plant through shoots and roots.

Also provides early postemergence crabgrass control when applied before the 3-leaf growth stage.

ethofumesate

Chemical class Mode of action Application timing
not classified unkown, evidence suggests inhibition of leaf wax formation. preemergence and postemergence

Utilized primarily in turf for postemergence control of annual bluegrass. Absorbed by emerging roots and shoots, and is translocated to leaves. Postemergence applications are somewhat poorly absorbed by leaves with thick, well-developed cuticles.

Also provides preemergence control of barnyardgrass, common chickweed, crabgrass, purslane and yellow foxtail, and some yellow nutsedge suppression. Ethofumesate is not prone to leaching.

fenoxaprop-ethyl

Chemical class Mode of action Application timing
aryloxyphenoxyprionate inhibits biosynthesis of fatty acids in sensitive plants postemergence

Controls annual grassy weeds, especially large and smooth crabgrass, goosegrass, barnyardgrass, yellow foxtail, sandbur and Japanese stiltgrass.

Application rate depends on weed growth stage. Some broadleaf herbicides when tank-mixed with or applied within a certain period of time can reduce the efficacy of fenoxprop as a result of herbicide antagonism. Can be tank-mixed with preemergence crabgrass herbicides to obtain residual control. Drought stress can significantly reduce efficacy. No soil activity.

ferric-HEDTA

Chemical class Mode of action Application timing
not classified iron toxicity postemergence

Ferric-HEDTA is a selective broadleaf herbicide. It is effective at cooler temperatures, rain-fast in a short period of time and results can be seen in as little as 24 to 48 hours.

Ferric-HEDTA is quickly absorbed by the leaf tissue and transported down to the root. The leaf tissue turns black or brown and death the of the weed follows.

forasulam

Chemical class Mode of action Application timing
sulfonanalide inhibits biosynthesis of certain essential amino acids postemergence

Controls bedstraw, common chickweed, mouse-ear chickweed, white clover, dandelion, dandelion, fleabane, groundsel, prostrate knotweed, shepherd’s-purse and spurge.

fluroxypyr

Chemical class Mode of action Application timing
pyridine disrupts growth by mimicking naturally occurring plant hormones. postemergence

Broad-spectrum material, especially effective for chickweed, cinquefoil, creeping woodsorrel, dandelion, ground ivy, henbit, plantain, purslane, white clover, wild strawberry, and yellow woodsorrel.

Either formulated alone and in pre-mixed combinations with other broadleaf herbicides. Absorbed by roots and shoots and is strongly translocated within the plant. Induces an epinastic (leaf curling) response and death occurs in days or weeks.

glufosinate-ammonium

Chemical class Mode of action Application timing
not classified causes metabolic changes that disrupt photosynthesis. postemergence

Glufosinate-ammonium is a non-selective herbicide.

Not translocated. Often poor to fair control of some perennial weeds. No soil activity.

glyphosate

Chemical class Mode of action Application timing
phosphonoglycine inhibits biosynthesis of certain essential amino acids postemergence

Glyphosate is a non-selective herbicide.

Strongly translocated and therefore very effective for perennial weeds. Symptoms include yellowing, starting with the youngest plant tissue, and progressing toward the oldest. Binds strongly to soil and does not leach. Glyphosate is not soil active.

halosulfuron

Chemical class Mode of action Application timing
sulfonylurea inhibits biosynthesis of certain essential amino acids postemergence

Halosulfuron is utilized in cool-season turf primarily for the control of yellow nutsedge.

Yellow nutsedge is best treated in the three- to eight-leaf stage of growth. The addition of a non-ionic surfactant is required. Halosulfuron is degraded by microbial activity in the soil and has a low potential for leaching.

isoxaben

Chemical class Mode of action Application timing
amide inhibits the biosynthesis of cellulose, disrupts root and hypocotyl development. preemergence

Controls a wide range of broadleaf weeds including black medic, carpetweed, dandelion, henbit, plantain, purslane, red sorrel, spurge, white clover, and yellow woodsorrel.

The only compound available exclusively for preemergence control of broadleaf weeds in cool-season turf.

mesotrione

Chemical class Mode of action Application timing
triketone disrupts carotenoid synthesis. preemergence and postemergence

When applied postemergence, mesotrione controls many broadleaf weeds including broadleaf plantain, carpetweed, common chickweed, clover, henbit, horseweed, purslane, purslane speedwell and yellow woodsorrel. Will provide postemergence control of creeping bentgrass, nimblewill, and yellow nutsedge as well. Also indicated for preemergence control of barnyardgrass, crabgrass, yellow foxtail and broadleaf annual weeds. Can be applied at the time of cool-season turf establishment for preemergence control. Symptoms in susceptible weeds include bleaching followed by necrosis.

Mesotrione is a synthetic analogue of the alleochemical leptospermone, which is produced by the roots of the “bottle brush” plant (Callistemon citrinus). Classified as a Reduced Risk pesticide by the US Environmental Protection Agency (EPA), for information visit https://www.epa.gov/.

oxadiazon

Chemical class Mode of action Application timing
protox inhibitor inhibits chlorophyll production, results in rapid destruction of cell membranes. preemergence

Primarily controls annual grasses (barnyardgrass, crabgrass and goosegrass) but also controls several broadleaf weeds (bittercress, carpetweed, smartweed, spurge, yellow woodsorrel).

Strongly adsorbed by soil colloids and therefore is not prone to leaching.

pendimethalin

Chemical class Mode of action Application timing
dinitroaniline interferes with cell division preemergence

Primarily used for preemergence control of crabgrass and other annual grasses including barnyardgrass, annual bluegrass, yellow foxtail, goosegrass and sandbur.  Also controls several broadleaf weeds including carpetweed, common chickweed, henbit, prostrate knotweed, purslane, spurge and yellow woodsorrel.

Pendimethalin is not prone to leaching

penoxsulam

Chemical class Mode of action Application timing
sulfonamide inhibits biosynthesis of certain essential amino acids. postemergence

Controls bittercress, broadleaf plantain, chickweed, dandelion, ground ivy, white clover and yellow wood sorrel.

Formulated alone and in combination with other selective herbicides on fertilizers and straight granules. Accepted for review and registration under the Reduced Risk Pesticide Initiative of the US Environmental Protection Agency (EPA), for information visit https://www.epa.gov/.

phenoxy herbicides (2,4-D, 2,4-DP/dichlorprop, MCPA, MCPP/mecoprop)

Chemical class Mode of action Application timing
growth regulator disrupt growth by mimicking naturally occurring plant hormones. postemergence

The phenoxy herbicides control a wide range of broadleaf weeds.

Systemic herbicides, but relatively slow acting. General symptoms on susceptible weeds include the twisting and curling of leaves and stems soon after application. Avoid application in hot weather. Products containing 20% or more 2, 4-D are classified as Restricted Use in Massachusetts. MCPA is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.

prodiamine

Chemical class Mode of action Application timing
dinitroaniline interferes with cell division. preemergence

Provides preemergence control of crabgrass, goosegrass, annual bluegrass and other annual grasses. Also controls several broadleaf weeds including carpetweed, chickweed, henbit, purslane, spurge and yellow woodsorrel.

Low water solubility and is strongly adsorbed to soil, therefore not prone to leaching.

pyraflufen-ethyl

Chemical class Mode of action Application timing
phenylpyrazole inhibits chlorophyll production, results in rapid destruction of cell membranes. postemergence

Controls carpetweed, chickweed, curly dock, dandelion, pineappleweed, purple deadnettle, purslane, round mallow, smartweed and spurge.

Contact herbicide. Formulated alone and in premixed combinations with other broadleaf herbicides.

quinclorac

Chemical class Mode of action Application timing
quinoline carboxylic acid unknown, thought to inhibit cell wall biosynthesis and mimic natural plant hormones. preemergence and postemergence

When applied postemergence, provides control of crabgrass, yellow foxtail, barnyardgrass, white clover, black medic, dandelion and speedwell. Also provides preemergence control of crabgrass and other annual grasses. Does not control goosegrass. Absorbed by foliage and roots and is translocated throughout the plant.

Formulated alone and in premixed combinations with other broadleaf herbicides. Postemergence treatments require addition of a methylated seed oil, crop oil concentrate or high quality surfactant for best control. Can be used before or after seeding or overseeding of cool-season turfgrasses for the control of crabgrass and other annual grasses. This compound should be used to control crabgrass before the 2-tiller and after the 5-tiller stage of growth.

siduron

Chemical class Mode of action Application timing
substituted urea root growth inhibitor; disrupts cell division. preemergence

Controls barnyardgrass, crabgrass, downy brome, and yellow foxtail. Does not control annual bluegrass, chickweed, clover, goosegrass and plantain.

Either formulated alone or on turf starter fertilizers. Unlike many other preemergence herbicides, siduron can be applied at time of seeding, on seedling turf and on sod to be harvested.

sulfentrazone

Chemical class Mode of action Application timing
protox inhibitor inhibits chlorophyll production, results in rapid destruction of cell membranes. preemergence and postemergence

Provides postemergence control of broadleaf weeds including carpetweed, common chickweed, mouse-ear chickweed, dandelion, henbit, lambquarters, narrowleaf plantain, Pennsylvania smartweed, purslane, spurge, star-of-bethelem, speedwell, yellow woodsorrel and creeping woodsorrel. Can be used to control or suppress yellow nutsedge and kyllinga.

Formulated alone and in premixed combinations with other broadleaf herbicides. Sulfentrazone is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.

topramezone

Chemical class Mode of action Application timing
pyrazolones disrupts carotenoid synthesis. postemergence
Provides effective control of barnyardgrass, large and smooth crabgrass, yellow foxtail,  fall panicum and Japanese stiltgrass. Very effective on goosegrass.

triclopyr

Chemical class Mode of action Application timing
pyridine disrupts growth by mimicking naturally occurring plant hormones. postemergence

Provides effective control of poison ivy, ground ivy, wild violets, and other difficult-to-control perennial weeds. Absorbed by roots and shoots and readily translocated throughout the plant.

Formulated alone and in premixed combinations with other broadleaf herbicides. The potential for leaching decreases with increasing soil organic matter and when conditions are favorable for soil microbial activity.

Table 12. Common herbicide products and their active ingredients

Herbicide product Active ingredient(s)
Acclaim Extra fenoxaprop-p-ethyl
Armor Tech CGC (40 & 40WP) dithiopyr
Armor Tech Quin Pro 75DF quinclorac
Balan 2.5G benefin
Barricade (4FL, 65WG, on-fertilizer formulations) prodiamine
Basagran T&O bentazon
Bensumec 4LF bensulide
Calvalcade PQ prodiamine and quinclorac
Cavalcade 65WDG prodiamine
Defendor florasulam
Dimension (2EW, EC, Ultra 40WP, on-fertilizer formulations) dithiopyr
Dismiss sulfentrazone
Drive (75DF, XLR8) quinclorac
Echelon 4SC prodiamine and sulfentrazone
Eject 75DF quinclorac
Fiesta ferric HEDTA
Finale glufosinate
Gallery isoxaben
Guardrail 65WDG prodiamine
Halosulfuron Pro halosulfuron
Jewel oxadiazon
Kade 65 WDG prodiamine
Knighthawk prodiamine
Manage halosulfuron
Pendulum (2G, 3.3EC, AquaCap) pendimethalin
PoaConstrictor ethofumesate
Pre-M (3.3EC, Aqua-Cap, on-fertilizer formulations) pendimethalin
Pre-San Granular (7G, 12.5G) bensulide
PrimeraOne Prodiamine 65WDG prodiamine
PrimeraOne Quinclorac 75DF quinclorac
PrimeraOne Prodiamine 65WDG prodiamine
Proclipse 65WDG prodiamine
Prograss ethofumesate
Prograss SC ethofumesate
Pylex topramezone
Quali-Pro Dithiopyr 40WSB dithiopyr
Quali-Pro Prodiamine 65WDG prodiamine
Quali-Pro Quinclorac 75DF quinclorac
Quin Pro quinclorac
Resolute (4L, 65WDG) prodiamine
Resolute (65WG, 4L) prodiamine
Ronstar (50WSP, FLO, G) oxadiazon
Ronstar G oxadiazon
Scythe pelargonic acid
SedgeHammer halosulfuron
SedgeHammer+ halosulfuron
Stonewall 65WDG prodiamine
Stonewall RQ prodiamine and quinclorac
Team (2G, Pro) benefin and trifluralin
Tenacity mesotrione
Tower dimethanamid
Tupersan siduron
Velocity SG bispyribac-sodium
Xonerate amicarbazone

 

Weed management with herbicides

  1. Crabgrass and other annual grassy weeds

    The first step in managing crabgrass and other annual grassy weeds, including yellow foxtail and goosegrass, is to insure that the cultural practices previously mentioned in this section are being completed on a routine basis. Fundamental cultural practices including mowing, fertilization, irrigation, and aeration when done correctly can significantly decrease annual grassy weed infestations. Cultural practices alone will seldom control crabgrass and other annual grassy weeds completely and there is commonly a need for herbicides to produce results that are commercially acceptable. An effective crabgrass management program utilizes a preemergence herbicide, followed by a postemergence herbicide as needed in the case of less than acceptable preemergence performance or the need to control “escapes”. With the exception of sites in which there are low populations of crabgrass and other annual grasses, postemergence herbicides should not be relied on as the sole control measure. In some situations, preemergence application can be split with 50% of the use rate being applied during the normal application window and the remaining 50% applied 4 to 6 weeks later.
    1. Preemergence materials
      Preemergence herbicides for the control of crabgrass and other annual grasses are applied in early spring. Applications in most areas of Massachusetts should be completed before Forsythia flowers drop or by approximately the first week in May, depending on prevailing weather conditions. Preemergence herbicides are available in sprayable and on-fertilizer formulations. These products need to be watered in to be activated and with the exception of very few materials (e.g. siduron, mesotrione), reseeding of turf cannot be done for three to four months after application. Refer to the product label for specific instructions in regard to safe reseeding intervals. Many annual broadleaf weeds can also be managed with preemergence herbicides.
       
      Active Ingredient Trade Name(s) Comments
      benefin Balan 2.5G, Team 2G (combination with trifluralin), on-fertilizer formulations  
      bensulide Bensumec 4LF, Pre-San Granular (7G, 12.5G), on-fertilizer formulations  
      corn gluten meal Many formulations available Corn gluten products are 9-10% N by weight and should be factored into fertility program.
      dithiopyr Armortech CGC 40, Crab and Spurge Preventer, Dimension (2EW, EC, Ultra 2SC, Ultra 40WP, Ultra WSP), Dynamo 40WSP, Lifeguard, Quali-Pro Dithiopyr 40WSB, on-fertilizer formulations  
      dimethenamid Tower  
      mesotrione Tenacity Can be used at the time of seeding or overseeding of cool-season turf.
      oxadiazon Ronstar (50WSP, FLO, G) Quali-Pro Oxadiazon 2G, Starfighter (3.17F, 2G), on-fertilizer formulations  
      pendimethalin Pendulum (2G, 3.3EC, AquaCap), Pre-M 3.3EC, on-fertilizer formulations (Halts, Pre-M)  
      prodiamine Barricade (4FL, 65WG), Cavalcade 65WDG, Echelon 45SC (combination with sulfentrazone, Guardrail 65WDG, Knighthawk, Quaili-Pro Prodiamine 65WDG, Stonewall 65WDG, Primeone Prodiamine 65WDG, Proclipse (4F, 65WDG), Resolute 65WDG, on-fertilizer formulations  
      quinclorac Armortech Quin Pro 75DF, Eject 75DF, Drive (75DF, XLR8), PrimeraOne Quinclorac 75DF, Quali-Pro Quinclorac 75DF Can be used before or after seeding or over-seeding of cool-season turfgrasses for the control of crabgrass and other annual grasses.
      siduron Tupersan (50WP, 4.6G), on-fertilizer formulations Can be used at the time of seeding or overseeding of cool-season turf.
    2. Postemergence materials
      Another strategy for managing crabgrass and other annual grasses is the use of postemergence herbicides. The most effective and economical control programs use a preemergence herbicide and a postemergence herbicide, if needed, to clean-up weed escapes.
       
      Active Ingredient Trade Name(s) Comments
      fenoxaprop-ethyl Acclaim Extra  
      dithiopyr Armortech CGC 40, Crab and Spurge Preventer, Dimension (2EW, EC, Ultra 2SC, Ultra 40WP, Ultra WSP), Dynamo 40WSP, Lifeguard, Quali-Pro Dithiopyr 40WSB, on-fertilizer formulations  
      quinclorac Armortech Quin Pro 75DF, Eject 75DF, Drive (75DF, XLR8), PrimeraOne Quinclorac 75DF, Quali-Pro Quinclorac 75DF, plus several combinations with broadleaf herbicides. Can be used before or after seeding or over-seeding of cool-season turfgrasses for the control of crabgrass and other annual grasses.
      mesotrione Tenacity  
  2. Broadleaf Weeds

    1. Preemergence materials
      Preemergence herbicide application for the control of broadleaf weeds in turf is not a common practice. Most often these weeds are controlled with postemergence broadleaf herbicides discussed in section 2B below. There are, however, some situations in which preemergence herbicides can be incorporated into an effective weed management program. Preemergence herbicides used for the control of crabgrass and other annual grass weeds (section 1A above) will effectively control many annual broadleaf weeds. The herbicides isoxaben and mesotrione are labeled for the preemergence control of many annual and perennial broadleaf weeds. These products need to be applied before weeds germinate.
       
      Active Ingredient Trade Name(s) Comments
      isoxaben Gallery The only material available exclusively for preemergence control of broadleaf weeds in cool-season turf.
      benefin, bensulide, dithiopyr, mesotrione, oxadiazon, pendimethalin, prodiamine, siduron Several preemergence herbicides used for the control of crabgrass and other annual grass weeds will effectively control many annual broadleaf weeds – see Section IA above.  
    2. Postemergence
      Annual and perennial broadleaf turf weeds can be managed with postemergence herbicides. Sprayable formulations are the most common but granular and on-fertilizer formulations are also available. Broadleaf weeds can be treated at any time of the growing season as long as weeds and cool-season turfgrasses are actively growing. Applications are best done in the fall and spring, avoiding periods when cool-season turfgrasses are heat and/or drought stressed. Winter annual broadleaf weeds that occur in late summer and fall turf seedlings can be controlled with broadleaf herbicides after the turf has received a minimum of three mowings. Postemergence broadleaf herbicides include the phenoxy herbicides (2,4-D, 2,4-DP/dichlorprop, MCPA, MCPP/mecoprop), carfentrazone, clopyralid, dicamba, fluroxapyr, quinclorac, penoxsulam, pyraflufen-ethyl, sulfentrazone and triclopyr. Broadleaf herbicide products are formulated as a single herbicide or in combinations of two, three or four herbicides, as summarized in Table 13:

      Table 13. Active ingredients in commercially-available postemergence herbicide products.
      Click to download Table 13 Adobe PDF icon
  3. Yellow Nutsedge

    Yellow nutsedge is one of the most difficult to control weeds in turf. Applications for yellow nutsedge should be made soon after spring and early summer emergence with application completed before the summer solstice. Heavy infestations can be treated with glyphosate.
    Active Ingredient Trade Name(s) Comments
    bentazon Basagran T&O, Nutgrass Nihilator 2 applications commonly needed. Bentazon is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.
    dimethanamid Tower Preemergence material for application where perennial stands of yellow nutsedge are known to exist.
    halosulfuron Manage, SedgeHammer, Halosulfuron Pro Addition of a non-ionic surfactant is required.
    mesotrione Tenacity  
    sulfentrazone Dismiss, Q4 Plus, Surge, Eschelon 4SC (combination with pendimethalin) Sulfentrazone is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.
  4. Annual Bluegrass

    Annual bluegrass is a winter annual with perennial biotypes being common in certain turf situations. Annual bluegrass germination occurs primarily in very late summer and fall. Ethofumesate and bispyribac-sodium are labeled for selective postemergence control in certain cool season turfgrass species. Annual bluegrass can be controlled with preemergence crabgrass herbicides when those materials are applied in late summer and fall before germination.
    Active Ingredient Trade Name(s) Comments
    ethofumesate Prograss, Poa Constrictor Applications are best made in the fall and 2 to 3 repeat applications at 3 to 4 week intervals may be needed.
    bispyribac-sodium Velocity SP, Velocity SG Labeled for use only on golf courses and sod fields.
    benefin, bensulide, dithiopyr, mesotrione (suppresses growth), prodiamine, pendimethalin Several preemergence herbicides used for the control of crabgrass and other annual grass weeds will effectively control or suppress annual bluegrass – see Section IA above.  
  5. Non-selective herbicides for turf renovation

    Non-selective herbicides are used to kill existing turfgrass, weeds and other vegetation before turf renovation. Using any of these herbicides for the spot-treatment of existing weeds in established turf is not recommended as turf injury or death will occur in the treated areas. The herbicide glyphosate is strongly translocated and therefore is the best option of the non-selective herbicides for use prior to turf renovation. Glufosinate is not as strongly translocated as glyphosate and therefore can be weak on perennial weeds. Glufosinate can be used when the weed population is comprised of only annual weeds. Pelargonic acid, acetic acid, citric acid, clove oil and d-limonene are contact in nature and will not control perennial weeds making them inappropriate to use in turf renovation.
    Active Ingredient Trade Name(s) Comments
    glufosinate Finale May be weak on perennial weeds.
    glyphosate Roundup Pro Max, GlyphoMate 41, many others  
    pelargonic acid Scythe Not appropriate for turf renovation.
    acetic acid, citric acid, clove oil, d-limonene various materials formulated alone or in combination Not appropriate for turf renovation.
  6. Selective perennial grass control

    Turf areas are often plagued by undesirables: cool-season and warm-season perennial grasses that disrupt uniformity and can result in an unacceptable turf. These grasses include creeping bentgrass, nimblewill, orchardgrass, paspalum, purpletop, quackgrass, tall fescue, timothy and zoysiagrass. A few herbicides are labeled for the selective control of certain grasses, however, most often the area is best treated with glyphosate and reestablished by seeding or sodding.
     
    Active Ingredient Trade Name(s) Comments
    chlorosulfuron Corsair Controls tall fescue, perennial ryegrass and annual ryegrass.
    glyphosate Roundup Pro Max, GlyphoMate 41, many others Spot or broadcast treatment on all species.
    mesotrione Tenacity Controls creeping bentgrass and nimblewill.
    metsulfuron Manor, MSM Controls perennial ryegrass.

 

Section 4: Insect Management

In this section:

Turf insects: damage and scouting

White grubs

Several species of grubs occur in New England. The most widespread species is the Japanese beetle. The European chafer is found in several locations in eastern and western Massachusetts (especially “inside” Route 495, and along the coast as far north as mid-coast Maine). The Oriental beetle is active in Connecticut, Rhode Island, coastal Massachusetts, and along the Connecticut River Valley. As a general rule European chafers and Oriental beetles are harder to manage than Japanese beetles. In addition, there have been a few occasions where Asiatic garden beetles have caused damage, although the damage from this species is usually most severe in less well maintained turf.

Management of white grubs is most efficient when the specific population causing turf damage is identified. Because some insecticides are less effective against Oriental beetle or European chafer, species identification has become increasingly important for management decisions. Identification of a white grub is made based on its raster pattern. A raster is the pattern of bristles on the underside of the last abdominal segment of the grub. Refer to Figure 1 for illustrations of the various grub rasters.

Damage - Damage from white grubs initially resembles drought stress, with general thinning and/or yellowing of turf. In some circumstances, skunks, raccoons or birds may tear apart turf in infested areas to feed on grubs near the surface, often dramatically increasing the extent of the damge.

Scouting - Use a shovel or spade to cut three sides of a square in the turf anywhere from 6” to 12” on a side, 3” to 4” deep. Flip the sod back on the uncut (fourth) side, turf side down, and use a hand trowel to dislodge soil in the soil/thatch interface. Alternatively, you can use a golf course cup cutter (4.25” diameter) to collect soil samples. The cream colored grubs will be very visible against the dark soil background. Place grubs in a container and count them after removing all of them from the sample area. Convert the area to square feet (e.g., 6” sides = 0.25 sq. ft.). Note that a standard golf course cup cutter is equivalent to 0.1 sq. ft. Take several samples and then calculate the average number of grubs found. For ease in averaging, make all sampling cuts the same size.

Note that weather and soil moisture conditions will affect grub behavior and movement. In very dry or very warm conditions, grubs will move deeper in the soil profile (so sampling holes must be dug deeper). In very moist conditions, grubs will either be closer to the surface or will move laterally to higher or better draining locations.

In the autumn or in early spring, grubs respond directly to soil temperatures. European chafers tend to remain in the root zone later in the fall and return to the root zone earlier in the spring than other species of grubs. Japanese beetles and Oriental beetles tend to respond to daily temperature fluctuations. On warm days in late fall or early spring, the grubs will move up into the root zone and feed, while on cold days or after very cold nights, grubs will remain several inches below the soil surface.

Figure 1. Raster patterns of turf-infesting grubs (drawings not to scale).

Adapted from Haruo Tashiro: Turfgrass Insects Of The United States And Canada. Copyright (©) 1987 by Cornell University. Used by permission of the publisher, Comstock Publishing Associates, a division of Cornell University Press.

Raster patterns of turf-infesting grubs

Black turfgrass ataenius

The black turfgrass ataenius (BTA) is a small species of white grub. The BTA life cycle is quite different from other grubs. It spends the winter in the adult stage, and females lay eggs in late spring. These eggs hatch into small grubs that feed throughout the month of June and into early July. In many years the grubs pupate and the new adults lay eggs in late July for a second generation. Black turfgrass ataenius is only a pest of concern on golf courses and other very low-mown sports turf (i.e. tennis, croquet) in New England.

Damage - Damage resembles that of other white grubs. Roots can be destroyed and damaged turf may peel back easily. Damage sometimes is more severe in areas with high levels of soil organic matter.

Scouting - Grubs can be found by taking a soil sample, cutting a small section of turf to a depth of 2” to 4” and inspecting the soil for tiny (less than 0.5”) grubs. Adults often are seen on the surface of putting greens, especially on warm sunny days in the spring. To scout for adults, force them to the surface with a soapy flush (irritating drench).

Chinch bugs

The hairy chinch bug (Blissus hirtus), the most common species in the Northeast, prefers ryegrass and fescues but will attack other lawn grasses as well. Adult chinch bugs are about 1/5-inch long and black with white markings on the wings. Nymphs (immature stages) have the same general shape as the adult but lack wings and often have red or orange markings.

Damage - Damage is often confused with drought stress, and normally occurs during July and early August. Injury (wilted or browned out areas) is most severe in sandy soils and in sunny areas. Small patches gradually coalesce into large areas of wilted or dead turf. Chinch bug-damaged turf may not recover in September when other turf comes out of drought dormancy.

Scouting - Use a cup cutter or similar device to remove cores of turf about 4” to 6” in diameter, place the cores in a bucket, and fill the bucket with water. Wait about five minutes. Chinch bugs (and big-eyed bugs, a beneficial insect) will float to the surface of the water. Chinch bugs can also often be observed directly by inspecting the foliage and thatch.

Sod webworms and cutworms

Sod webworms and cutworms are moths that cause damage to turf in the caterpillar stage of their development. In webworms, the color pattern varies with the species and plant source, but most are greenish, grayish, or brownish, and usually have dark spots scattered along the body. The black cutworm, the most common cutworm species in New England, is normally dark gray or nearly black but may have a hint of green in the stripes. Webworms are more likely to cause damage in lawn settings, while cutworms are more frequently encountered on golf courses and other closely-mown turf areas.

Damage - Damage usually begins as small discrete brown patches which can coalesce into larger areas of damage. A finger inspection of the infested area will sometimes reveal sod webworm burrows lined with green frass (insect excrement). Cutworms are often active around aerification holes on golf course greens.

Scouting - Prepare an irritating drench by mixing one fluid ounce of lemon scented dish detergent in one to two gallons of water in a pail. Spread this solution over an area about 2’x2’. Wait three to five minutes. Webworms and cutworms (and earthworms) will be irritated by the soapy solution and will crawl to the surface of the turf area. Note: The soapy solution can burn turf, so on sunny days, and on bentgrass or Poa annua turf, rinse the sample area with clear water after you have completed the insect count.

Annual bluegrass (Hyperodes) weevils 


The annual bluegrass weevil (Listronotus maculicollis, also sometimes referred to as the Hyperodes weevil) is a significant golf course pest in many parts of the Northeast and Mid-Atlantic states. Annual bluegrass weevil is only a pest of concern on golf courses and other very low-mown sports turf (i.e. tennis, croquet), and is not found in higher-cut turf. The insect overwinters in the adult stage. Adults emerge in the spring and migrate from overwintering sites to lay eggs in turfgrass leaf sheaths (almost exclusively annual bluegrass). Following egg hatch, feeding of the tiny larvae becomes increasingly more aggressive up until pupation and the final transition to the adult stage. The annual bluegrass weevil may complete two or three generations per year in New England.

Damage - The most severe damage normally occurs from early June through mid-August, with moderate damage possible at other times of the summer as well. Damage begins as small yellow patches, often along the edges of fairways or on collars around greens, and spreads into large areas. Severely damaged areas take on a water-soaked appearance. Damage is most often restricted to short cuts (fairways and shorter) of annual bluegrass. However, field observations have confirmed that annual bluegrass weevils will feed on creeping bentgrass under certain conditions.

Scouting - Use a cup cutter or similar device to collect cores of 4” to 6” diameter. Loosely break up the soil in the cores and place the loosened soil and all plant matter in a dish pan or similar plastic container. Fill the container with lukewarm water and wait about five minutes. Weevils in all stages of development (except eggs) will float to the surface of the water, where they can be counted. You can also use a saturated salt solution to force larvae to the surface of the water. Large larvae and pupae are visible in turf samples without using flotation techniques. A leaf blower can be reversed and used to vacuum adults from an infested area. Insert a gauze bag in the end of the tube to collect the insects.

Bluegrass billbugs


Bluegrass billbugs can cause serious damage to lawns, particularly those which are predominantly bluegrass. They occur sporadically in New England. Billbug adults are black beetles with very elongated “snouts.” The total body length is about 1/4-to 3/8 -inch and the tail end is somewhat pointed. Despite the name, bluegrass billbugs will feed and even thrive on most cool season turf species.

Damage - Look for evidence of damage along the edges of paved areas in mid- to late July. Bluegrass billbug infested areas begin to wilt but do not respond to watering. As larvae feed in the stems and on the roots, damaged turf can be tugged loose with very little force. Infested areas will brown out entirely in a matter of several days. Damage is usually most severe in July and August. Damaged turf often does not recover in September and renovation may be necessary.

Scouting - Larvae can be found by digging into the root/thatch interface with a hand trowel and inspecting the area. Accumulations of “sawdust-like” material (billbug excrement) will be found in the thatch.

Invasive craneflies


The European cranefly (Tipula paludosa) is an invasive species that has become a pest in western New York and southern Ontario (Niagara Peninsula). The common (or marsh) cranefly (Tipula oleracea) is another invasive species that has become established in western New York and Long Island. T. oleracea has been recently reported from several areas in Massachusetts, including Martha’s Vineyard, Cape Cod, and several suburbs south and west of Boston. Adults (which resemble large mosquitoes) emerge in late August or September. Females lay 200 to 300 black eggs near the soil surface. Small larvae feed from October through February, (when temperatures are mild). Larvae normally feed in the top inch of the soil, feeding on roots and root hairs. Larvae can be found within 3 inches of the surface, even in the winter months (larvae wriggle to the surface and can be seen projecting out of the turf. They pupate mid-March to mid-April. New adults emerge, lay eggs, and the resulting larvae feed through the summer months. They pupate in mid- to late-August, and adults emerge in September to complete the cycle.

Damage - Damage may resemble grub damage, especially in higher cut turf, because the larvae destroy roots. Animals and birds may cause turf damage while foraging for the larvae, as is also frequently the case with white grubs. On closely-mown turf, such as tees and greens, the damage might resemble cutworm feeding or aerification holes with the edges nibbled away.

Scouting - Watch for flights of ‘large mosquitoes’ in the spring and late summer. For larvae, take a soil sample (a cup cutter plug to a depth of about six inches often works well) and break the soil apart. The larvae are olive green to dark brown and quite active, often within the top inch of soil or in the thatch. Larvae can occasionally be seen at the surface feeding on turfgrass foliage on warm, humid nights.

Ants


Ants can be beneficial because they are often predators of other insects.

Damage - Several species of ants occur in turf and can disrupt the surface when building mounds. The turfgrass ant (Lasius neoniger) forms numerous mounds of 0.5” to 2.0” diameter on closely mown turfgrass, such as golf course fairways. These mounds are unsightly and can dull or damage mower blades. In the process of building tunnels, ants can break off roots and root hairs or increase desiccation of the soil.

Scouting - Rough estimates of ant activity can be obtained by counting the number of mounds in a given area.

Insect threshold levels

The key to any Integrated Pest Management program is the identification of response (or “action”) threshold levels. There is no single magic number which will be appropriate for all turf situations. Thresholds are given as first approximations only, and should be used only as guides.

Several agronomic factors will have a direct effect on the number of insects a turf area can tolerate. Some of these factors include the species of turfgrass, the height of cut, availability of irrigation (and resulting soil moisture distribution), use patterns (including traffic and other sources of compaction), and the fertility program. The thresholds presented in Table 14 are for unirrigated turf and are provided as guidelines only. In most cases, irrigated turf can sustain higher insect populations without showing stress.

Actual response thresholds will depend on the overall vigor of the turf being managed, the use of the turf, the presence of secondary pests such as skunks and raccoons, and the quality expected.

Table 14. Approximate threshold levels* for turfgrass insect pests.
INSECT Approximate threshold per sq. ft.
Japanese beetle 8 to 15 larvae
Oriental beetle 8 to 15 larvae
Masked chafer 8 to 15 larvae
European chafer 3 to 8 larvae
Asiatic garden beetle 12 to 20 larvae
May beetle (Phyllophaga) 2 to 4 larvae
Black turfgrass ataenius 15 to 80 larvae
Annual bluegrass weevil 10 to 80 larvae
Bluegrass billbug No good estimate available
Chinch bug 30 to 50 nymphs
Sod webworm, cutworm No good estimate available
* Please note that actual threshold levels will vary based on site conditions, management practices, and/or turf use.

 

Biological management of turf insects

Paenibacillus popilliae


Milky disease (sometimes called “milky spore”) is caused by a bacterium, Paenibacillus popilliae, which occurs naturally in soil and affects the digestive system of Japanese beetle grubs. According to tests conducted in New Jersey, there is no evidence that milky disease is effective against other species of grubs. It is relatively nontoxic to people and other “non-target” organisms.

Milky disease is somewhat inconsistent in the Northeast. More turf managers have reported success with milky spore in the sandy soils of southeastern Massachusetts than in other areas. In any case, the milky disease organism may take several months to become effective; in some cases it may remain effective for three to five years. The discovery of “milky looking” grubs while monitoring may indicate that a milky spore application has taken hold. However, sporadic natural infestations of milky disease do occur, so the mere presence of milky grubs does not necessarily indicate that an application will be effective or consistent. Studies conducted in Kentucky indicate that there is no evidence that commercial preparations of P. popilliae increase the incidence of milky disease significantly in field populations.

Bacillus thuringiensis (Bt)

Bacillus thuringiensis (Bt) is a bacterium that causes disease in several kinds of insects. Recently several new strains of Bt have been identified that are quite specific in the kinds of insects they attack. Because they are more specific, they can be used in a turf setting without disrupting some of the natural enemies, such as predator beetles and mites, which are present.

The strain which is effective against caterpillars (particularly cutworms and sod webworms) is known as the “kurstaki” strain, and is available commercially (some products are not registered for turf use, so check the label carefully before purchasing or using any formulations). The material is formulated to be applied to the turf with a hydraulic sprayer. As with several of the biological control agents currently available, Bt kurstaki is most effective when directed against small stages of caterpillars (less than 0.25” long). Bt kurstaki will not kill caterpillars immediately after exposure, but it will paralyze the gut and digestive system very quickly after the insect ingests the material, so feeding activity stops soon after exposure. Currently, there are no published field trials available reporting the effectiveness of Bt kurstaki for caterpillar control in turf.

A newer strain of Bt (japanensis, or ‘buibui’) appears very promising based on field trials targeting Oriental beetle and Japanese beetle grubs, but looks less effective against European chafers and Asiatic garden beetles. It must be applied when grubs are just beginning to hatch (usually early to mid-August). This strain is not currently under commercial development.

Beauveria bassiana


Beauveria bassiana is a fungus that occurs naturally in New England turfgrass, and is favored by wet conditions in the spring. The fungus is a natural enemy of chinchbugs. B. bassiana is sometimes available commercially, but no field trials have been conducted (and published) to determine whether commercial applications will reduce pest populations.

Entomopathogenic nematodes

Entomopathogenic nematodes are small, microscopic worms which attack insects. Certain species of these nematodes have proven to be quite effective against some of the surface feeding insects (cutworms, sod webworms). The preparations, consisting of live organisms, must be handled more carefully than traditional insecticides. For example, they are temperature-sensitive, so the containers must be stored in areas that will not get too hot (above 80° to 85°) and will not freeze.

Entomopathogenic nematodes can be applied through standard hydraulic sprayers (although very fine filters should be removed). However, these nematodes are very sensitive to desiccation. To maximize their effectiveness, nematodes should be applied in early morning or late afternoon (not between 10 a.m. and 2 p.m.) and should be watered in immediately. In addition, nematodes are most effective when the target insects are small.

There are several species of nematodes which are commercially available in the United States at this time. Steinernema carpocapsae is available as several trade names. Studies throughout the Northeast indicate that this species of nematode is not particularly effective against white grubs, but it can be effective against caterpillars in turf (sod webworms and cutworms). Many turf managers do not rely on nematodes for caterpillar control, however, because they tend to be inconsistent. If nematodes are used to target caterpillars, they must be applied when caterpillars are small (less than 0.25 inch long), and must be watered in with at least 0.25 inch water.

Several field studies have been conducted over the past five years, testing the effectiveness of entomopathogenic nematodes against annual bluegrass weevils (ABW). The results have been inconclusive — occasionally there appears to be a reduction in larval populations in the first generation, but the “window of opportunity” (when larvae are susceptible) appears to be about five to seven days each spring. The nematode showing the most promise is Steinernema carpocapsae, but more field testing must be completed before golf course superintendents can be confident using nematodes for ABW control.

Heterorhabditis bacteriophora (HB) is also available under many different trade names, and field trials in Massachusetts indicate that it can reduce white grub populations when used properly. However, studies conducted at Rutgers University indicate that HB is much more effective against Japanese beetle grubs than other species of grubs. When targeting grubs, nematodes must be applied when grubs are present but still small (often mid August to early September) and must be watered in with at least 0.25 inch of water.

Neem

Azadirachtin is a derivative of the neem tree, which grows in India and other tropical settings. The compound repels several kinds of insects and often causes them to stop feeding. Neem also acts as an insect growth regulator on some insects, preventing them from molting normally from one stage to the next. There is an indication that the neem compounds may sometimes reduce populations of the surface feeders (cutworms and sod webworms). Some commercial applicators report that applications of azadirachtin have been inconsistent. Also, some azadirachtin formulations are very viscous and difficult to handle in a sprayer.

Spinosad

Spinosad (Conserve) is a synthetic preparation of a soil actinomycete which is often categorized as a biological control material, even though it is synthetic and produced in large facilities. It has provided significant control of larval populations of annual bluegrass weevil in the first generation in several field trials. It must be applied as the larvae are emerging from the stems, before they reach their largest (fourth and fifth) instars. Spinosad is also very effective against caterpillars in both turf and landscape setings.

Beneficial insects in the turf setting

If a turf manager were to take a cup cutter sample from a turf area which had not been treated with insecticides for a year or two, and extracted all of the insects and other arthropods from that sample, that manager would be amazed at the diversity of arthropod life in the sample. There are countless beneficial insects and close cousins active in the thatch and upper root zone, decomposing organic matter or preying on other insects. Some of the predatory arthropods include ground beetles (most of which feed on insect eggs and small soft bodied insects, such as small caterpillars or aphids), predatory mites, spiders, and ants. Some of the decomposers include springtails (often in huge numbers), saprophytic nematodes, symphylans, and some mites. While we do not yet fully understand the role of each of these creatures, we do know that their role is crucial to thatch management, and to the overall health of the turf.

Unfortunately, some of the insecticides that are currently used in turf settings are “broad spectrum” materials, which means they kill a wide range of insects and other arthropods, including many beneficial insects. If these broad spectrum insecticides are used regularly, the balance of beneficial insects may change over time, so that fewer of the predators or decomposers remain active. As a result, pest populations can build up more rapidly following an application, because some of the natural enemies have been destroyed and are no longer available to provide a natural level of control of the target pest.

It is critical, therefore, that insecticide applications should be made only when sampling has demonstrated that a pest population has reached the threshold level, and only to areas for which infestation has been confirmed through careful monitoring.

Big-eyed bugs are naturally occurring predators that can be found in many New England turf settings. They are very effective predators of chinchbugs, but unfortunately they look very similar to chinchbugs (except for big bulging eyes), so sometimes insecticide applications are made that reduce big-eyed bug populations. These predators are not available commercially.

Endophytic turfgrass cultivars

Endophytic cultivars have within the seed and plant itself a beneficial fungus called an endophyte. The fungus is unable to live outside of the seed or plant, and so it depends upon the plant for its survival. The plant also benefits from its association with the fungus. Endophyte-enhanced cultivars tend to be vigorous even under conditions of stress such as minimal fertilization and irrigation, and exhibit a level of resistance to foliar feeding insects such as sod webworms, and in particular chinchbugs and billbugs. Endophytes impart no tolerance or resistance to root feeding insects such as white grubs. Furthermore, cultivars which contain endophytes may vary in their susceptibility or in their resistance to disease. This factor is not as clear cut as insect resistance, and will vary by cultivar as well as by disease.

At present there are some endophytic cultivars of perennial ryegrass, tall fescue, creeping red fescue, hard fescue and chewings fescue available. When repairing lawns and other areas that have been damaged by surface feeding insects such as chinchbugs, billbugs, or sod webworms, select endophytic cultivars of appropriate turfgrasses whenever possible. Keep in mind that the percent of endophyte infection in a cultivar may differ by seed lot. Also, the level of endophyte in old or improperly stored seed will decrease as the fungus loses viability. Check with a reputable seed supplier for cultivars with endophyte, as well as for level of endophyte in a particular seed lot.

Endophytic turfgrass cultivars should not be used where animals may graze. The alkaloids produced by the endophyte and the interaction of the endophyte with the plant not only impart some degree of insect resistance to the plant, but also have the potential to sicken animals that may feed upon the plant.

Characteristics of turf insecticides

Some turf insecticides act very quickly while others take much longer to kill the target insect. In addition, some materials persist for several weeks and remain active, while others break down in a matter of a few days. Of the insecticides listed in these guidelines, a few work quite quickly (within one to three days) and break down within one to two weeks. These materials, often used for ‘curative’ applications, include: acephate (Orthene), and trichlorfon (Dylox). Some of the synthetic pyrethroids, like cyfluthrin (Tempo) and bifenthrin (Talstar) begin to act quickly but will persist longer if they penetrate the thatch and/or are applied to the soil.

Very few of the turf insecticides currently available for use in Massachusetts are intermediate in their “speed of efficacy” and persistence. These materials will often take three to seven days to begin to affect the target insects, but normally will remain active for three to five weeks, and sometimes even longer. Several “intermediate” materials have been taken off the market in the last few years, one that remains is carbaryl (Sevin).

Some insecticides, such as imidacloprid (Merit) or chlorantraniliprole (Acelepryn), are used for preventive insect control in areas that have a history of damage.  This use pattern is common for white grub management, but care must be taken to ensure that the material is in place and fully active when the grubs are in the most susceptible stage. These materials vary in how quickly they become active, but then normally remain active for several weeks or even months.
Please note that some listed materials have been somewhat inconsistent in their performance while others have provided similar levels of control through the years. Be sure to obtain current label information before using any insecticide.

Using insecticides preventively in an IPM program

Insecticides usually have either preventive or curative action against the pest for which they are used. Preventive materials are applied before a noticeable pest population develops. Curative materials are typically applied after populations reach a damaging level.

There are many components to an IPM program, including monitoring for pest activity, establishing tolerance levels, and considering cultural and biological management strategies whenever possible. One of the key tenets of IPM is to apply pesticides when a pest population exceeds a threshold level and only when all other avenues of control have been exhausted. In certain instances, however, preventive pesticide applications may be preferred to the alternative of waiting until a problem develops.  Part of the process in selecting and applying pesticides in an IPM program is to use application methods and materials that minimize the potential for environmental disruption.

For example, several turf insecticides [including the neonicotinoids and chlorantraniliprole (Acelepryn)] provide preventive protection against white grubs and are much less toxic than the older organophosphate materials that were used for many years. There are few cultural practices or effective biological control agents available that provide reliable control of white grub populations. Furthermore, in Massachusetts the use of the most effective curative material, trichlorfon (Dylox), is not allowed on school properties as specified in the Children and Families Protection Act (see the Pesticide Regulations section of this guide for more information). The only option for effective management of high populations of white grubs in this circumstance is preventive application with a neonicotinoid or chlorantraniliprole.

To be justified in an IPM plan, preventive insecticide applications must be based on scouting or other documentation of the potential for damaging populations from the previous season or seasons.

Insecticide resistance


There are several chemical classes of insecticides available to turf managers. Recently some turf insects (most notably, the annual bluegrass weevil) have developed resistance to certain chemical classes (in the case of the weevil, resistance to pyrethroids). This means that applications of certain products made now at rates that were effective several years ago do not kill as many insects. One of the most effective ways to delay the development of resistance is to avoid using insecticides in the same chemical class repeatedly. In most cases, you must also avoid using chemicals with the same mode of action. The Insecticide Resistance Action Committee (www.irac-online.org) has assigned “IRAC” numbers for each chemical class, and many chemical companies are putting these numbers on labels to make it easier for turf managers to incorporate this information into their decisions on chemical inventories. For example, any insecticide in the neonicotinoid class (e.g., Merit or Meridian or Arena) will have a black box with a white “4A” indicating the IRAC chemical subgroup. Carbamates (class 1A) and organophosphates (class 1B) are in the same group but listed separately because while the chemistry of the two classes of insecticides is different, the mode of action (cholinesterase inhibition) is the same.

The following information on insecticide characteristics will help turf managers avoid using the same chemical class repeatedly. Trade names referenced here are the first trade name under which the product was available in turf. Note that for some chemicals, there are many additional trade names not listed here.

Table 15. Characteristics of turf insecticides registered for use in Massachusetts.

ABW = annual bluegrass weevil; BTA = black turfgrass ataenius; ECF = European crane fly

Chemical class: ORGANOPHOSPHATE OR CARBAMATE IRAC class: carbamate – 1A; organophosphate – 1B
Most are “older” chemicals and, as cholinesterase inhibitors, tend to be more acutely toxic to vertebrates than some of the newer compounds. There is a lot of variation in field characteristics: Some are soluble in water while others are not; some are systemic while some are not; some are quite persistent while some are not. For example, trichlorfon (Dylox) and acephate (Orthene) are very soluble in water and can break down quickly when water pH is above 7.5. Neither is very persistent in field conditions. Most other insecticides in these classes are being phased out of the turf market.
Common name Trade name Partial list of insects on label Notes
acephate Orthene caterpillars, chinchbugs  
carbaryl Sevin caterpillars, many beetle adults, chinchbugs, ECF Very toxic to honeybees and other bees
chlorpyrifos Dursban billbug adults, caterpillars, chinchbugs, ECF Golf course only. Actively being phased out of the market and available only as generic formulations.
trichlorfon Dylox white grubs Works quickly, breaks down quickly. Susceptible to rapid breakdown with water pH above 7.0-7.2
 
Chemical class: PYRETHROID IRAC class: 3
Every pyrethroid available for use on turf is virtually insoluble in water and is bound quickly to organic matter. As a result, pyrethroids are effective against insects that are active in the thatch (e.g., annual bluegrass weevil adults, black turfgrass ataenius adults, bluegrass billbug adults, caterpillars, chinchbugs, European crane fly). ABW has developed resistance to pyrethroids in some locations, particularly between Hartford, CT and metropolitan NY. Most pyrethroids begin working three to five days after application (sometimes more quickly) and remain active for three to five weeks (sometimes longer). Labels on pyrethroids sometimes change, and there may be additional products labeled for turf that are not listed here. Most pyrethroids are toxic to fish and aquatic invertebrates, and some are also toxic to bees that are exposed to direct treatments on flowering crops and weeds. Some of the pyrethroids that are used in New England are listed below. Many pyrethroids have gone “off patent” so there are many other products available with different trade names.
Common name Trade name Partial list of insects on label Notes
bifenthrin Talstar ants, ABW adults, BTA adults, billbugs, caterpillars, chinchbugs, ECF  
cyfluthrin Tempo ants, ABW adults, BTA adults, billbugs, caterpillars, chinchbugs, ECF  
lambda-cyhalothrin Scimitar ants, ABW adults, BTA adults, billbugs, caterpillars, chinchbugs, ECF  
deltamethrin Deltagard ants, ABW adults, BTA adults, billbugs, caterpillars, chinchbugs, ECF  
 
Chemical class: NEONICOTINOID IRAC class: 4A
There are four neonicotinoids currently available in turf, and all of them are systemic through the roots.  Imidacloprid works much more slowly than most of the other insecticides available for turf. However, it appears to remain active for several weeks, and even a few months in some cases. Two of the neonicotinoids (chlothianidin and thiamethoxam) are also absorbed directly into leaf tissue to some degree. As a result they tend to work a little more quickly than imidacloprid and appear to be active on a slightly wider range of turf insects. None of the neonicotinoids are effective against Asiatic garden beetles. Neonicotinoids often take several days to start working, but remain active for several weeks or months (depending on the time of year they are applied). Even though imidacloprid has been on the turf market for more than 10 years, there have been no reports of resistance in any turf insects yet. There have been some implications that use of imidacloprid might be a contributing factor to colony collapse disorder in honeybees, but there are also many other possible explanations for that disorder. Care should be taken when using any neonicotinoid to avoid applications when honeybees are foraging, such as when clover or ground ivy is in bloom. In addition, some labels indicate products are toxic to aquatic invertebrates.
Common name Trade name Partial list of insects on label Notes
chlothianidin Arena ABW, BTA, caterpillars, billbugs, white grubs  
dinotefuran Zylam   More soluble than the others, optimum use patterns still being identified. Dinotefuran is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.
imidacloprid Merit ABW, BTA, billbugs, white grubs Merit went “off patent” in 2007
thiamethoxam Meridian ABW, BTA, caterpillars, billbugs, white grubs Thiamethoxam is regulated under the Public Drinking Water Supply Protection Regulations in MA, see the Pesticide Regulations section of this guide for details.
 
Chemical class: COMBINATION PRODUCTS IRAC class: neonicotinoid, 4A; pyrethroid, 3
Three products are now available for commercial applicators that combine a neonicotinoid and a pyrethroid. The combination provides protection against soil insects (neonicotinoid) and surface feeders (pyrethroid). Optimal timing of application depends on what the primary insect target is at a given site. (For example, if white grubs are the primary target, applications should be made just as adults become active and start laying eggs. If billbugs are the primary target, applications could be made in late May or early June to target adults as they become active.)
Trade name Contents Partial list of insects on label Notes
Allectus Merit and Talstar ABW, BTA, billbugs, caterpillars, chinchbugs, ECF, European chafer, Japanese beetle, and oriental beetle. available only to commercial applicators
Aloft Proprietary blend of chlothianidin and bifenthrin ABW, BTA, billbugs, caterpillars, chinchbugs, ECF, European chafer, Japanese beetle, and oriental beetle. available only to commercial applicators
Maxide Meridian and Scimitar ABW, BTA, billbugs, caterpillars, chinchbugs, ECF, European chafer, Japanese beetle, and oriental beetle. available for general use
Other generic combination products are also available.
 
Chemical class: OXADIAZINE IRAC class: 22
There is only one product currently available in turf that is in the oxadiazine class: indoxacarb. This class has a very low mammalian toxicity and a new mode of action. It works by blocking the movement of sodium ions into nerve cells. Product labels have the same precautionary language as pyrethroids regarding toxicity to fish and aquatic invertebrates, as well as foraging honeybees. Indoxacarb is particularly effective against caterpillars and is most effective when applications are made targeting eggs and small caterpillars.
Common name Trade name Partial list of insects on label Notes
indoxacarb Provaunt ABW larvae, caterpillars  
indoxacarb Advion turfgrass ants (bait formulation)  
 
Chemical class: ANTHRANILIC DIAMIDE IRAC class: 28
This new chemical class has a totally new mode of action and has such low mammalian toxicity, the EPA did not require the registrant to include a signal word on the label. It received federal registration in April 2008 and at least one formulation has been registered in each of the New England states. The label describes chlorantraniliprole as toxic to aquatic invertebrates, but it is relatively insoluble so it is less likely to move to surface water than some other products. It is not toxic to bees, ants, or wasps. It is extremely effective against all the white grub species we encounter in New England, but should be applied before early to mid June to achieve maximum effectiveness against grubs. Spring applications of chlorantraniliprole will not affect grubs that are present in the spring.
Common Name Trade name Partial list of insects on label Notes
chlorantraniliprole Acelepryn ABW, BTA, billbugs, caterpillars, white grubs  
 
Chemical class: SPINOSYN IRAC class: 5
This group is represented by spinosad (Conserve), which is derived from a soil actinomycete. The label describes it as highly toxic to bees and to mollusks. Effective against many caterpillars, including sod webworms, cutworms, and armyworms (as well as caterpillars in the landscape). Also a good larvacide for annual bluegrass weevil.
Common name Trade name Partial list of insects on label Notes
spinosad Conserve ABW larvae, caterpillars Apply against ABW larvae when larvae have just begun to emerge from the stem

 

Insect management with insecticides

Table 16: Labeled insecticides and ideal application timing for common turf insect pests in New England.

Insect Insecticide Ideal Timing Comments
White grubs
(Japanese beetle, European chafer, Oriental beetle, Asiatic garden beetle, etc.)
carbaryl (Sevin)   when grubs are present Sometimes inconsistent, sensitive to high pH. Very toxic to honey bees. Not available for use on school grounds in Massachusetts.
chlothianidin (Arena) when adults are laying eggs A neonicotinoid, not effective against Asiatic garden beetle (AGB). May have some curative properties in late summer applications.
chlorantraniliprole (Acelepryn) mid April to early June Not effective against grubs present in spring.
imidacloprid (Merit) when adults are laying eggs Merit went off patent in 2007, many generic forms now available. A neonicotinoid, not effective against AGB. Not effective against grubs present in spring
thiamethoxam (Meridian) when adults are laying eggs A neonicotinoid, not effective against AGB
trichlorfon (Dylox) when grubs are present Best option to control grubs in spring. Can be used into mid September most years. Sensitive to high pH. Not available for use on school grounds in Massachusetts.
Allectus when adults are laying eggs combination product – Merit + Talstar (not effective against AGB)
Aloft when adults are laying eggs combination product – proprietary blend of chlothianidin and bifenthrin (not effective against AGB). May have some curative properties in late summer applications.
Maxide when adults are laying eggs combination product – Meridian + Scimitar (not effective against AGB)

Scouting: Scout for adult activity in mid-July to mid-August by scouting nearby foliage and/or use black light traps for European chafers. Scout for larvae in late summer or early spring with soil samples. Check the root/thatch interface for presence of grubs in late July to late August.

Treatment: Treat when adults are laying eggs (mid-June to early August) if using a neonicotinoid. Treat between mid-August and mid-September to moist soil if grub population averages at least 5 to 10 grubs per square foot if using an intermediate or fast-acting material. Water in (at least 0.25”) immediately after application, but avoid puddling. If population was not controlled in late summer, apply spring control as soon as grubs are near surface (normally in April). Note that some materials have been inconsistent while others have performed consistently well over the years.

 
Insect Insecticide Ideal Timing Comments
Annual bluegrass weevil
(Hyperodes weevil)
bifenthrin (Talstar) Forsythia half green, half gold to dogwood full bloom  
chlorantraniliprole (Acelepryn) Two weeks after Forsythia half green, half gold Also controls white grubs and caterpillars
chlorpyrifos (Dursban) Forsythia half green, half gold Golf course use only. Generic formulations only.
cyfluthrin (Tempo) Forsythia half green, half gold to dogwood full bloom  
lambda-cyhalothrin (Battle, Scimitar) Forsythia half green, half gold to dogwood full bloom  
deltamethrin (Deltagard) Forsythia half green, half gold to dogwood full bloom  
indoxacarb (Provaunt) when larvae first emerge (Rhododendron catawbiense full bloom) May need to make two applications. Also effective against caterpillars.
spinosad (Conserve) when small larvae present (Rhododendron catawbiense full bloom)  
trichlorfon (Dylox) when small larvae present (Rhododendron catawbiense full bloom)  

Scouting: Scout for adult activity in mid- to late April with soapy flush. Monitor for larval activity in late May through June with soil samples, flotation, and visual inspection of thatch layer or collect samples, submerge in saline solution.

Treatment: When targeting adults, treat between Forsythia and flowering dogwood “full bloom” (usually late April to mid-May). Treat for second generation if necessary during first two weeks of July. Water lightly (0.05” to 0.1”). Most applications are best targeted against adults as they begin to lay eggs or against young larvae. When targeting larvae, treat at Rhododendron catawbiense full bloom. Many annual bluegrass weevil (ABW) populations in the Northeast have developed resistance to pyrethroids. While not every population is resistant, golf course superintendents should try to minimize their reliance on pyrethroids whenever possible. Cultural strategies that may help reduce larval populations or minimize damage include converting Poa annua to creeping bentgrass, raising the height of cut where possible, and removing pine litter from nearby white pines. Monitor the areas where ABW are active and target larvae with one of the larval treatments as soon as they are observed.

 
Insect Insecticide Ideal Timing Comments
Black turfgrass
ataenius adults
bifenthrin (Talstar) Forsythia half green, half gold to dogwood full bloom  
chlorpyrifos (Dursban) Forsythia half green, half gold to dogwood full bloom Golf course use only. Generic formulations only.
cyfluthrin (Tempo) Forsythia half green, half gold to dogwood full bloom  
lambda-cyhalothrin (Battle, Scimitar) Forsythia half green, half gold to dogwood full bloom  
deltamethrin (Deltagard) Forsythia half green, half gold to dogwood full bloom  
Black turfgrass
ataenius grubs
chlothianidin (Arena) mid May to early June  
imidacloprid (Merit) mid May to early June  
thiamethoxam (Meridian) mid May to early June  
trichlorfon (Dylox) when larvae present (often late June)  
Allectus late April to early June combination product – Merit + Talstar
Aloft late April to early June combination product – Arena + generic bifenthrin

Scouting: Look for adults, sometimes in very large numbers, on putting greens in April (or use a soapy flush to force them to the surface). Large numbers of adults do not necessarily lead to heavy grub populations. Monitor for grubs from mid-May through mid-August by soil sampling.

Treatment: If treating for adults (before egg laying), apply Dursban or a pyrethroid between Forsythia full bloom and dogwood full bloom, (late April to mid-May) and again two weeks later. Water in lightly (0.05” to 0.1”). Use this approach only in areas where BTA populations have been unusually high in previous years, to avoid treating areas that do not have populations high enough to warrant control. If treating for larvae, apply a material which will penetrate the thatch when horse chestnut or Van Houette spirea are in full bloom, (usually early June). Water in with at least 0.15” to 0.3” of water immediately after application. Imidacloprid or chlothianidin can be applied preventively, but should not be applied earlier than early June if white grubs are also a problem.

 
Insect Insecticide Ideal Timing Comments
Chinch bug bifenthrin (Talstar) June - July  
chlorpyrifos (Dursban) June - July Golf course use only. Generic formulations only
cyfluthrin (Tempo) June - July  
lambda-cyhalothrin (Battle, Scimitar) June - July  
deltamethrin (Deltagard) June - July  
Allectus June to mid July combination product – Merit + Talstar
Aloft June to mid July combination product – Arena + generic bifenthrin
Maxide June to mid July combination product – Meridian + Scimitar

Scouting: Scout for adult activity in May and early June, for immature stages throughout summer. In addition, chinch bugs move steadily in the thatch and can be seen by using fingers to spread the turf.

Treatment: Populations are commonly highest in fine fescues and turf stands with thick thatch. Use endophyte containing cultivars when available; avoid drought conditions. Apply in June; water in lightly (less than 0.1”) after application. In some cases, a second application two to three weeks later may be needed.

 
Insect Insecticide Ideal Timing Comments
Cutworm bifenthrin (Talstar) when damage appears  
carbaryl (Sevin) when damage appears Very toxic to honey bees. Not available for use on school grounds in Massachusetts. Repeat applications may be needed, especially after heavy rain.
chlorantraniliprole (Acelepryn) mid May to mid June Several weeks of protection when applied at high label rate.
chlorpyrifos (Dursban) when damage appears Golf course only. Generic formulations only.
cyfluthrin (Tempo) when damage appears  
deltamethrin (Deltagard) when damage appears  
indoxacarb (Provaunt) June – July Often provides several weeks protection.
lambda-cyhalothrin (Battle, Scimitar) when damage appears  
Spinosad (Conserve) when damage appears  
Allectus June to mid July combination product – Merit + Talstar
Aloft June to mid July combination product – proprietary blend of chlothianidin and bifenthrin.
Maxide June – July combination product – Meridian + Scimitar

Scouting: Monitor adult activity with black light traps. Apply insecticides two to three weeks after peak flights. Scout for caterpillars (late in the day or early in the morning) with soapy flushes.

Treatment: Most cutworms are nocturnal, so treatments are most effective if applied late in the day. Water lightly (less than 0.10”). On golf courses inspect aerification holes throughout summer. Damage often becomes most noticeable shortly after aerification, particularly in late summer. Apply two to three weeks after peak moth flight.

 
Insect Insecticide Ideal Timing Comments
Sod webworm bifenthrin (Talstar) when damage appears  
carbaryl (Sevin) when damage appears Very toxic to honey bees. Repeat applications may be needed, especially after heavy rain. Not available for use on school grounds in Massachusetts.
chlorantraniliprole (Acelepryn) mid May to mid June Several weeks of protection when applied at high label rate.
chlorpyrifos (Dursban) when damage appears Golf course use only. Generic formulations only.
cyfluthrin (Tempo) when damage appears  
lambda-cyhalothrin (Battle, Scimitar) when damage appears  
deltamethrin (Deltagard) when damage appears  
indoxacarb (Provaunt) June – July  
Spinosad (Conserve) June – July  
Allectus June – July combination product – Merit + Talstar
Aloft June – July combination product – proprietary blend of chlothianindin and bifenthrin
Maxide June – July combination product – Meridian + Scimitar

Scouting: Monitor adult activity by inspecting turf surface at twilight looking for small “tube moths” flitting just above the canopy. Scout for caterpillars with soapy flushes.

Treatment: Check for sod webworm activity: look for small green pellets in upper thatch or flush an area with soapy water. Watch for webworm moths flying at twilight. Apply controls 10 to 14 days after number of moths declines sharply. Repeat applications may be necessary. Treat as late in day as possible. Water lightly (0.10”); do not mow for one to three days after application.

 
Insect Insecticide Ideal Timing Comments
Invasive craneflies, preventive bifenthrin (Talstar) mid September to mid October Apply when larvae are mostly first and second instars.
carbaryl (Sevin) mid September to mid October Very toxic to honey bees. Apply when larvae are mostly first and second instars. Not available for use on school grounds in Massachusetts.
chlorantraniliprole (Acelepryn) mid September to mid October Preliminary trials look promising.
chlothianidin (Arena) mid September to mid October Apply when larvae are mostly first and second instars.
indoxacarb (Provaunt) mid September to mid October Apply when larvae are mostly first and second instars.
Aloft mid September to mid October combination product – proprietary blend of chlothianidin and bifenthrin
Invasive craneflies, curative chlothianidin (Arena) when larvae are small Apply when larvae are mostly third instars.
indoxacarb (Provaunt) when larvae are small Apply when larvae are feeding actively in spring.
Aloft when larvae are small combination product – proprietary blend of chlothianidin and bifenthrin

Scouting: “Common” cranefly (Tipula oleracea) larvae occasionally can be seen at the surface feeding on foliage on warm, humid nights. Check for larval activity by taking soil samples (cup cutter plugs), dislodging the soil and looking for the dark-colored larvae. In late summer look for pupal skins that jut out from the surface. Also watch for adults flying just above the turf surface or landing on walls of buildings.

Treatment: Normally the larvae survive best in areas that have high soil moisture during the fall and spring. Withholding irrigation during the time when females are laying eggs may reduce larval survival. There are two approaches for controlling cranefly larvae. Preventive applications are made when larvae are first and second instars (usually mid September to mid October), while curative applications are made when larvae are third and fourth instars (usually mid March to mid April). Water lightly to moderately (0.05 to 0.15 inch) to move product into the thatch and enhance contact with the larvae. A second generation occurs with egg laying in April or May and larvae feeding from mid May through late August.

 
Insect Insecticide Ideal Timing Comments
Turfgrass ants
(Lasius neoniger)
bifenthrin (Talstar) when new mounds appear  
chlothianidin (Arena) when new mounds appear Studies in other states indicate spring applications can provide control for several weeks
chlorpyrifos (Dursban) when new mounds appear Golf course use only. Generic formulations only.
cyfluthrin (Tempo) when new mounds appear  
lambda-cyhalothrin (Battle, Scimitar) when new mounds appear  
deltamethrin (Deltagard) when new mounds appear  
hydramethylnon (Maxforce) when new mounds appear Bait – do not water in
imidacloprid (Merit) when new mounds appear Studies in other states indicate spring applications can provide control for several weeks
indoxacarb (Advion) when new mounds appear Bait – do not water in
Aloft when new mounds appear or in mid to late August combination product – proprietary blend of chlothianidin and bifenthrin. Bifenthrin provides quick relief, chlothianidin provides longer coverage

Scouting: Scout for turfgrass ants by watching for new mounds on the surface.

Treatment: Turfgrass ants produce mounds on turf that are unsightly and can dull mower blades. The traditional approach has been to apply a pyrethroid or chlorpyrifos to the new mounds as soon as they appear (typically late April or early May). These surface applications kill many of the workers and weaken the colony but the only way to eliminate a colony is to kill the queen. The most effective way to eliminate the queen is to use a bait formulation, which workers will carry to the brood chamber. Baits should not be watered in, while surface applications can be watered in lightly (less than 0.10 inch).

 

Table 17. Insect treatment calendar.

  Mar Apr May Jun Jul Aug Sep Oct
One year grubs: Japanese beetle, European chafer, masked chafer, Oriental beetle, Asiatic garden beetle                                                                
                                                               
                                                               
2 or 3 year grubs: May or June beetles. Best time is July of year the eggs are laid. Second best time is spring after eggs are laid.                                                                
                                                               
                                                               
Hyperodes weevil                                                                
                                                               
                                                               
Black turfgrass ataenius (adult)                                                                
                                                               
                                                               
Black turfgrass ataenius (larvae)                                                                
                                                               
                                                               
Chinch bugs                                                                
                                                               
                                                               
Billbugs                                                                
                                                               
                                                               
Sod webworms                                                                
                                                               
                                                               
Cutworms                                                                
                                                               
                                                               
Ants                                                                
                                                               
                                                               
  periods where damage is most likely to occur
  best time to treat (specific timing depends upon material selection)
  second best time to treat (specific timing depends upon material selection)

 

Section 5: Disease Management

In this section:

Scouting for turf diseases

The following key is patterned after Shurtleff (1987) in “Controlling Turfgrass Pests” but has been adapted to turfgrass diseases common in Massachusetts. The four sections include COLD, COOL/WARM, and HOT temperature diseases as well as problems not generally related to temperature.

Technical terminology has been minimized. The word “mycelium” (or hyphae) refers to the web-like growth of fungi on turf when wet. “Black specks” are the spore containers produced by a few of the disease causing fungi. “Sclerotia” are dark, pinhead-sized or slightly larger masses of mycelium that some fungi produce as survival structures.

How to use this key

Decide first the temperature when symptoms first appeared. Then read the subsections to decide which best describes the problem. Symptoms of diseases are often quite different on lawns than on highly maintained, low-mown turf such as putting greens. The most common diseases are indicated by a star (★).The diagnosis of turf diseases can be difficult even in the laboratory. Use this key only as a general guide. For information about disease diagnostic services available from UMass, refer to the UMass Extension Plant Diagnostic Lab at ag.umass.edu/services/plant-diagnostics-laboratory.

Section I. Cold Weather (32–45°F) Diseases and Disorders

A. Irregular patterns or streaks in turf.

  1. Bleached or dead grass, especially in wind-swept areas free of snow with deeply frozen soil. WINTER DESICCATION
  2. New leaves killed back, often in yellow to white patches following freezing temperatures. SPRING FROST

B. Turf killed (rotted or straw-colored) in wettest areas.

  1. May follow drainage patterns. WATER AND ICE DAMAGE
  2. Distinct circular patches of dead grass from 1” to 3” across.
    1. Wet grass is often covered with white to bright pink mycelium; NO sclerotia present. « MICRODOCHIUM PATCH (PINK SNOW MOLD)
    2. Wet grass covered with white to gray or bluish-gray lint-like mycelium; small yellow to dark brown or reddish sclerotia often present in or on grass leaves. « TYPHULA BLIGHT (GRAY OR SPECKLED SNOW MOLD)

Section II. Cool-to-Warm Weather (45–75°F) Diseases

A. Circular patches or rings in turf after grass greens up in spring.

  1. Yellow patches or “tufts” usually less than 1” across. Plants easily pulled from turf. DOWNY MILDEW (YELLOW TUFT)
  2. Sunken, straw-colored patches, 1” to 6” across. May be covered with dense white mycelium in moist weather.
    1. Whitish tan leaf spots with brown, reddish brown or purplish borders. ★ DOLLAR SPOT
    2. Turf wilted, killed, rotted or straw-colored. Often in poorly drained areas. PYTHIUM ROOT ROT
    3. Leaves yellowing and wilting; tiny black, spiny fungal hairs in tufts may be evident with a hand lens. ★ ANTHRACNOSE (CROWN/BASAL ROT)
  3. Patches from 1” to 3’ across.
    1. A prolonged cool rain commonly following melting snow. Wet grass is often covered with white to bright pink mycelium or may be greasy to coppery in color. ★ MICRODOCHIUM PATCH (PINK SNOW MOLD)
    2. Patches usually with green centers.
      1. Yellow to straw colored, sunken in high cut turf. Wet grass not covered with mycelium. ★ YELLOW PATCH (COOL WEATHER BROWN PATCH)
      2. Initially yellow, then reddish brown or bronzed, and finally sunken, tan rings. Centers often invaded by weeds. Most commonly found in cool, moist, coastal areas; most common in bentgrass. « TAKE-ALL PATCH
      3. Patches, rings, arcs, “frog-eyes” about 6” to 8” across, enlarging later. Most common in Kentucky bluegrass sod two to four years old and annual bluegrass. ★ NECROTIC RING SPOT
  4. Rings or arcs up to 15’ or more across; often with outer ring of dark green grass; may be mushrooms in rings; often dead turf on highly managed areas in golf course. ★ FAIRY RING

B. Irregular patterns (usually) in turf.

  1. Colored fungus or spores on leaf surfaces; leaf spots not usually evident.
    1. White to gray powdery mycelium and spores on leaf surfaces; found mostly in shade. ★ POWDERY MILDEW
    2. Gray to black streaks of black powdery spores in leaves; leaves shred into ribbons and curl. Grass may later die in irregular patches or a general thinning; usually in turf three or more years old. LEAF SMUTS
    3. Pink to reddish and mycelium flecks on leaves; red thread-like growths beyond leaf tips; appears tan in patches; most common in low nitrogen turf. ★ RED THREAD/PINK PATCH
    4. Bright yellow, orange, or reddish-brown pustules of powdery spores on leaf blades; mostly late summer, usually on slow growing and low fertility turf. ★ RUSTS
    5. Slimy, superficial whitish gray to yellow fungus-like material in the early stages; turns powdery later. SLIME MOLDS
  2. Irregular patches of turf lacking distinct fungal signs.
    1. Increased leaf senescing on annual bluegrass (indicated by tan patches) or purpling of bentgrass on putting green height turf. Turf may also be off-color, thin or slow-growing in variably-sized patches. PYTHIUM ROOT DYSFUNCTION
  3. Leaves distinctly spotted or with tip blight.
    1. Oval to eye-shaped, dark-bordered spots. In warm weather, turf may look thin and weak (melting-out). ★ LEAF SPOTS AND BLIGHTS/MELTING OUT

Section III. Hot Weather (over 75°F) Diseases

Occur from late spring to late summer.
Possibilities from previous sections

Circular patterns in turf:

  • Dollar Spot
  • Necrotic Ring Spot

Irregular Areas:

  • Rusts
  • Slime Molds

A. Circular patterns in turf.

  1. Straw colored patches often 6” to 8” across, but can be larger; centers often remain green. Most common on Kentucky bluegrass sod two to four years old and in annual bluegrass. Symptoms often appear in hot weather after heavy rains. Symptoms identical to necrotic ring spot.  SUMMER PATCH
  2. Patches up to 2’ to 3’ across; light brown; grass blades usually not matted. Patches appear during wet periods. Gray mycelium may be visible in moist conditions; most common on bentgrass greens (look for “smoke ring”) and tall fescue lawns (distinct tan or chocolate brown lesions on leaf blades).  BROWN PATCH
  3. Tan leaf spots without darker borders. Grass leaves matted and slimy. Copious amounts of dense gray/white mycelium in moist weather.  PYTHIUM BLIGHT
  4. Yellow/golden brown rings (3” to 12” in diameter) on annual bluegrass putting greens. Rare on creeping bentgrass. Rings may have scalloped appearance and enlarge over time. BROWN RING PATCH (WAITEA PATCH)
  5. Circular patches (1” to 2” diameter). Tan dead tissues with reddish-brown borders on young, sand-based bentgrass putting greens. BENTGRASS DEAD SPOT
  6. Circular copper or salmon colored patches less than 3” in diameter, during humid weather. Most common on golf course putting greens. COPPER SPOT

B. Irregular patterns of weak, thin, dormant or dead grass. Large areas appear dry, then wilt, and turn brown.

  1. Turf is yellowish, then reddish brown. Leaves spotted to blighted. Tiny black, spiny fungal hairs in tufts on blades evident with hand lens. Most common in compacted, stressed turf. Most common on annual bluegrass golf course putting greens.  ANTHRACNOSE (CROWN/BASAL ROT)
  2. Oval or eye-shaped leaf spots with dark margins, mostly on Kentucky bluegrass. « LEAF SPOTS/BLIGHTS/MELTING OUT
  3. Irregular gray to brown leaf spots with dark margins and yellow halo. Mostly on perennial ryegrass and tall fescue. GRAY LEAF SPOT
  4. Recently seeded areas have irregular, empty areas due to poor germination. Dying and dead seedlings have dark or black coloration. DAMPING-OFF, SEED ROT
  5. Irregularly thinning turf, soil surface with has green or black coating that is slimy to the touch. ALGAE
  6. Irregularly thinning turf, soil surface has a thick, silvery green mat. MOSSES

Section IV. Other Causes of Poor Turf Usually Independent of Temperature.

A. Turf gradually becomes pale green to golden yellow and grows slowly; stand often thins out.

  1. Definite leaf lesions or mottling present. AIR or SOIL POLLUTION
  2. Yellow streaks may form parallel to the leaf veins. IRON or NITROGEN DEFICIENCY

B. Turf suddenly appears scorched.

  1. Usually in patches, bands or streaks. CHEMICAL BURN or MOWER BURN
  2. Bands, streaks, or irregular patterns; grass is stimulated at margins. FERTILIZER BURN
  3. Ring of dark green grass at margins; patches up to about 1’ across. DOG INJURY
  4. Entire turf area or patches over slight elevations or mowing corners are yellow to brown. SCALPING INJURY
  5. Leaf tips are shredded; appear gray, then tan. DULL MOWER INJURY

C. Round to irregular patches of dead or dormant grass; often follows dry periods. BURIED DEBRIS, INSECT INJURY or THICK THATCH

D. Turf bare or thinned; often in traffic areas, dense shade, waterlogged soil, etc.

  1. Greenish to brown scum that later forms a black crust. ALGAE
  2. Small green plants that grow on soil in slight mounds. MOSS
  3. Soil hard in heavily tracked paths, under swings, etc. COMPACTION

E. Turf dry, bluish green (footprints visible), wilts may later turn brown. DROUGHT, WILT or IMPROPER WATERING

 

Cultural management of turf diseases

Though it can be challenging to maintain intensively-managed turfgrass without fungicides, good cultural practices will reduce the need for fungicide applications and make necessary applications more effective. In fact, effective and well-timed cultural practices may minimize or eliminate the need for fungicide applications in lawns and other less intensely maintained turfgrass areas.

Starting right 


Prepare the site well. Remove stumps, construction materials and other debris. Improve drainage where necessary, and fill in low areas. Test soil pH and adjust to 6.0 to 7.0 if required. Break up soil clumps to provide a uniform area for seed or sod.

Choose seed or sod carefully (see Turfgrass Selection: Species and Cultivars). Inspect sod for diseases or other problems. Choose high quality, pathogen-free seed. Many disease resistant cultivars are now available and should be included in blends and mixtures. Genetic variability in turfgrasses will reduce the chance for epidemics that kill or damage large areas of turf.

General landscaping decisions can have significant impacts on turf health. Pruning of tree branches may increase light penetration to allow better turfgrass growth. Trees, shrubs, and other plantings should be placed to allow good air circulation, so turf will dry quickly after rain or dew. In very shady areas, shade-tolerant turfgrass cultivars or other groundcovers should be planted.

Seed should be planted only in well prepared soil with good drainage when temperatures stay in the range to allow rapid germination and establishment. Keep soil and seed moist, but do not over-water.

Routine Care

Fertilizers - Apply according to current recommendations and based on a soil test. Excess nitrogen will cause succulent growth that is more susceptible to disease. Avoid nitrogen applications (especially water soluble/quick-release fertilizers) during leaf spot season early in spring, during hot, humid weather, and just before dormancy in fall, which may leave turf more susceptible to snow molds and winter injury. Be sure, however, to meet the minimum nitrogen requirement for the turfgrass species and use as some diseases (e.g. red thread, rusts, and dollar spot) are encouraged when nitrogen is deficient.

Herbicides - Herbicides can stress turfgrasses and make them more susceptible to diseases. Apply carefully according to label directions and with attention to environmental conditions.

Some herbicides may have fungistatic effect and provide some degree of disease control. Noting fungistatic occurrences may be useful for reducing the amount of fungicide applied, by applying fungicides in combination with fungistatic herbicides.

Liming - Adjust pH according to soil test recommendations. Disease occurrence may increase at pH extremes (too high or too low). Lime applied late in autumn can increase Microdochium patch (pink snow mold) incidence and high pH can predipose turf to take-all patch infection during the spring. 



Mowing - Mowing wounds turfgrasses and can spread pathogens (disease-causing organisms). Minimize wounding and shredding of grass blades by keeping mower blades sharp and adjusted properly. If possible, mow when the turf is dry. Mow as high as possible for species and the turf use, using the maximum mowing height in hot weather. Avoid mowing more than one-third of the total height at each cutting to reduce stress to the root system. Mowing in autumn until turf stops growing can help to reduce damage from snow molds.

Watering - Water is necessary for good plant growth, but too much water floods open spaces in the soil, depriving roots of oxygen. Disease-causing fungi reproduce by spores that, like seeds, need water to germinate and infect turf. Dry turfgrass blades reduce disease by reducing infection. Deep and infrequent watering is strongly preferred to shallow, frequent watering to minimize leaf wetness and to encourage an extensive root system. Every effort should be made to not extend the duration of time blades are wet from dew or irrigation. Do not water in late afternoon or early evening. Night irrigation after dew appears may help conserve water, but is not recommended on hot, humid nights because it can increase some diseases (Figure 2). Avoid light, frequent sprinklings (syringing) except to prevent wilting in close-cut or shallow rooted turf and during hot, dry weather. In certain situations, keeping upper soil layers moist may help to reduce the occurrence of necrotic ring spot and summer patch.

Figure 2. When NOT to water turf

 

Thatch - Thatch is mostly composed of partially decayed above- and below-ground lateral stem tissue (stolons and rhizomes). A thin layer is beneficial in most turf situations. When thatch is more than 1/2” thick, it reduces nutrient and water absorption and harbors insect pests and disease pathogens. Prevent excessive thatch formation by providing adequate fertility in combination with aeration, verticutting and topdressing when needed. Mechanical removal of thatch is disruptive and should be accomplished in spring and late summer when time and conditions will allow for sufficient turf recovery.

Compaction - Several diseases (e.g. necrotic ring spot, summer patch, or athracnose basal rot) are worse in areas with compacted soil. Core aeration can help relieve soil compaction and improve turf quality. On some sites, traffic management may also be appropriate to minimize soil compaction.

Targeted cultural practices

Some sites have a history of disease problems, while others exist in a growing environment conducive to certain diseases.  For some pathogens, targeted cultural practices can go a long way towards preventing disease occurrence, reducing severity of disease when it does occur, and promoting recovery from damage. Table 18 details cultural management strategies for some of the most common turf diseases encountered in the Northeast.

Table 18. Cultural management strategies for common turf diseases.

Disease (Pathogens) Turfgrass Hosts* Season Cultural Management Strategies
Algae, Mosses all turfgrasses Apr – Nov Improve fertility and drainage. Alleviate compaction. Modify shade-causing agents to increase light penetration.

Anthracnose (Crown/Basal Rot)
Colletotrichum cereale

bentgrasses, annual bluegrass Mar – Sept Provide adequate N fertility. Avoid stress from too little or too much water and compaction. Raise mowing height.
Bentgrass Dead Spot Ophiosphaerella agrostis bentgrasses less than 6 years old on sand-based root zones. June – Sept Add N. Rake out and reseed.

Brown Patch
Rhizoctonia solani

all turfgrasses, tall fescue, bentgrasses, perennial ryegrass July – Sept In hot weather, avoid excess N and excess water. Avoid night watering. Remove dew from putting greens.

Brown Ring Patch (Waitea Patch)
Waitea circinata

annual bluegrass, rough bluegrass, creeping bentgrass Dec – July Apply adequate N for rapid recovery from damage. Dethatch and improve drainage. Symptoms can often be masked with N or iron.

Copper Spot
Gloeocercospora sorghi

bentgrasses June – Sept Avoid excess N. Minimize leaf wetness. Plant resistant cultivars.
Damping-off, Seed Rot
several fungi including Pythium spp., Fusarium and Rhizoctonia solani
all turfgrasses Apr – Oct Ensure careful seedbed preparation. Use good quality seed. Maintain soil moisture but avoid overwatering.

Dollar Spot
Sclerotinia homoeocarpa

all turfgrasses, bentgrasses, annual bluegrass June – Sept Avoid N deficiency and water stress. Minimize leaf wetness. Relieve compaction and excess thatch. Raise mowing height.
Downy Mildew (Yellow Tuft) Sclerophthora macrospora all turfgrasses May – Sept Avoid excess N and excess watering. Iron sulfate may mask symptoms. Improve drainage.
Fairy Ring (various fungi) all turfgrasses April – Nov Mask symptoms with N or iron. Core aerate and water. Fumigate or remove soil in severe cases.

Gray Leaf Spot
Pyricularia grisea

perennial ryegrass, tall fescue July – Nov Avoid excess N. Minimize leaf wetness. Reduce shade, lower mowing height.

Leaf Smuts
Ustilago striiformis

bentgrasses, Kentucky bluegrass April – Nov Avoid excess N in spring. Avoid water stress. Plant resistant cultivars. Collect clippings and discard.
Leaf Spots and Blights/ Melting Out
“Helminthosporium” spp. Ascochyta, Bipolaris, Curvularia, Drechslera, Nigrospora, Septoria, Leptosphaerulina
all turfgrasses, Kentucky bluegrass, bentgrasses, fine fescues April – Oct Avoid excess N, especially in spring. Raise mowing height. Minimize leaf wetness. Plant resistant cultivars.
Necrotic Ring Spot Ophiosphaerella korrae Kentucky bluegrass, esp. sod (3-4 yrs old), fine fescues, annual bluegrass June – Sept Avoid water and fertility stress. Avoid compaction and excess thatch. Utilize slow release N sources.

Powdery Mildew
Blumeria graminis

Kentucky bluegrass, fine fescues July – Sept Reduce shade and increase air circulation. Avoid excess N.

Pythium Blight
Pythium spp.

all turfgrasses, perennial ryegrass, bentgrasses June – Aug Avoid excess N and night watering in hot weather. Do not mow when wet or when disease is active. Improve drainage and air circulation.
Pythium Root Dysfunction Pythium volutum creeping bentgrass Sept – June Avoid excess N. Improve drainage. Aerate Regularly.

Pythium Root Rot
Pythium spp.

all turfgrasses, bentgrasses and annual bluegrass in sand greens Mar – Nov Improve drainage. Increase soil organic matter.
Red Thread Laetisaria fuciformis and Pink Patch Limonomyces roseipellis all turfgrasses, perennial ryegrass, fine fescues April – Oct in mild, wet weather Avoid N deficiency, water stress, and low pH. Minimize leaf wetness. Water deeply and infrequently. Improve light penetration and air circulation.

Rusts
Puccinia spp.

all turfgrasses, Kentucky bluegrass, perennial ryegrass July – Oct Avoid N deficiency and water stress. Minimize leaf wetness. Plant resistant cultivars. Reduce thatch. Raise mowing height and collect clippings. Water deeply and infrequently.

Slime Molds
various organisms

all turfgrasses June – Sept Mow or hose away. Fungicide applications are not necessary.
Snow Molds: Pink Snow Mold (Microdochium Patch) Microdochium nivale and Gray or Speckled Snow Mold (Typhula Blight) Typhula spp. all turfgrasses, bentgrasses Nov – April Avoid lush growth in fall. Continue mowing until autumn growth ceases. Avoid prolonged snow cover; do not allow excessive piling of snow on turf and reduce drifting with placement of snow fences. Fertilize lightly in spring to promote re-growth.

Summer Patch
Magnaporthe poae

fine fescues, annual bluegrass, Kentucky bluegrass July – Sept Avoid water stress and overwatering. Avoid compaction. Maintain adequate fertility. Lower pH in top inch of soil. Raise mowing height. Utilize slow release forms of N. Apply 2 lb/A MnSO4 annually in spring.

Take-all Patch
Gaeumannomyces graminis var. avenae

bentgrasses Mar – June Sept – Nov Avoid heavy lime applications. Lower pH in top inch of soil. Improve drainage. Apply acidifying fertilizers.

Yellow Patch (Cool Weather Brown Patch)
Rhizoctonia cerealis

bentgrasses, Kentucky bluegrasses, perennial ryegrass Nov – April Avoid excess N. Minimize leaf wetness. Improve drainage and air circulation.
* The most susceptible turfgrass species are in bold italics.

 

Biological management of turf diseases

At this time, many research programs are investigating biological controls for turf diseases. The two main areas of emphasis are the use of organic composts and the use of specific microbes that inhibit disease-causing fungi. There are some new commercial products for the biological control of turf diseases that consist of specific microbes, and many potential products are currently under study. Several organic composts have exhibited some suppression of certain diseases, but much more research is needed before recommendations can be made. Such composts are thought to contain microbial populations that inhibit disease-causing fungi. Different composts inhibit certain diseases but not others; other composts do not appear to suppress disease at all.

Genetic resistance can also be considered a form of biological control because certain turfgrass cultivars are resistant to or tolerant of some diseases. Selection of disease-resistant cultivars or disease-immune species is a priority in many turfgrass breeding programs. If a certain disease is a continuing problem, it can be helpful to investigate the availability of new disease-resistant cultivars that can be used for over-seeding or reestablishment of damaged areas. See Turfgrass Selection: Species and Cultivars for information on disease tolerant cultivars that are well-adapted to Massachusetts conditions.

There is little doubt that the use of biological control products and improved genetic resistance will become a more significant part of turfgrass disease management in the near future. However, these new alternatives will work best as part of an integrated disease management program that includes a strong cultural approach to reduce stress factors and minimize opportunities for infection by pathogenic fungi.

Characteristics of turf fungicides

Most common turfgrass diseases are caused by fungi. Fungicides kill or inhibit the growth of fungi.

There are two general categories of fungicides:

  • contact/protectant
  • penetrant

Contact/protectant fungicides remain on the outside of the plant and protect the plant from new infection. They must be applied at comparatively short intervals that can range from 5 to 14 days, because the fungicides are degraded by ultraviolet light, washed from the leaf surface by irrigation or rain, or mowed away. These fungicides do not have curative activity and new growth is not protected. Thorough coverage of plant tissue is critical to successful protection. Examples of contact/protectant fungicides commonly used in turf include captan, chlorothalonil, chloroneb, etridiazole, fluazinam, fludioxonil, mancozeb, maneb, PCNB, and thiram. 


Penetrant fungicides are absorbed into plant tissue and may provide some curative action. The duration of control afforded by penetrant fungicides is often much longer than that offered by contact fungicides, and some redistribution into new tissue may occur as the plant grows. Application intervals vary, but often range from 14 to 21 days and longer. According to specific topical modes of action, penetrant/systemic fungicides can be further divided into three sub-categories:

  • Localized penetrants form a protective barrier on the plant surface and permeate into the leaf in the area where deposition occurred. These fungicides have some curative activity, but do not move upward or downward inside the plant. Examples include iprodione, polyoxin D zinc, trifloxystrobin, and vinclozolin.

  • Acropetal penetrants form a protective barrier on the plant, permeate into the plant, and move upward in the plant’s xylem. These fungicides have protective activity including new growth, and have good curative activity. Examples include azoxystrobin, fenarimol, mefenoxam, and triadimefon.

  • Systemic penetrants form a protective barrier on the plant, permeate into the plant, move upward in the plant’s xylem, and move downward in the plant’s phloem. These fungicides have protective activity including new growth, and have good curative activity. Of the currently available penetrant/systemic fungicides, only fosetyl-Al (Aliette Signature) is truly systemic and moves both upward and downward in the plant.

Refer to Table 20 for a list of available fungicide materials and their respective topical modes of action.

Fungicide resistance

Some fungicides are site specific in their mode-of-action. This means that it takes very little genetic change on the part of a fungus for resistance to occur. Resistance may result in poor disease control, meaning that higher application rates or shorter intervals are needed to maintain healthy turf, or complete control failure. Resistance may develop suddenly or gradually depending on the fungicide involved. Once resistance has developed in a fungal population, it may last for a long time or gradually disappear if the fungicide is no longer used, depending on the fungicide and site-specific factors. Resistance is common for some diseases, but not observed for others. Fungicide resistance has been documented for anthracnose, dollar spot, Microdochium patch, gray leaf spot, and Pythium blight. 


The best strategy is to try to prevent, or at least delay, resistance. All penetrant fungicides are at risk for resistance development due to their “single-site” mode-of-action. Contact/protectant fungicides are unlikely to result in resistance because most of them have “multi-site” modes-of-action with the exception of fludioxonil (Medallion) and a few others which have a “single-site” mode-of-action. There are multiple chemical groups with different biochemical modes-of-action for broad-spectrum disease control in turfgrass that are at risk for resistance. Fungicide resistance has already been reported in five of these groups (Benzimidazole, Dicarboximide, Demethylation Inhibitor (DMI), Strobilurin (QoI) and Phenylamide). 


Table 19. Turfgrass pathogens and chemical classes with documented fungicide resistance.

Turfgrass Disease (causal agent) Resistance to chemical classes (see Table 20)
Benzimidazole Dicarboximide DMI QoI Phenylamide
Anthracnose (Colletotrichum cereale) X   X X  
Dollar spot (Sclerotinia homoeocarpa) X X X    
Gray leaf spot (Pyricularia grisea)       X  
Microdochium patch/pink snow mold (Microdochium nivale)   X      
Pythium blight (Pythium aphanidermatum)         X

Mix or alternate between different site-specific chemical groups or with multi-site contact/protectant fungicides, indicated by different FRAC (Fungicide Resistance Action Committee) code numbers, to prevent or delay the development of resistance. Changing fungicides by brand or trade name will not prevent resistance if the active ingredient or chemical group is the same. Fungicide labels list the active ingredient(s) in smaller letters below the brand name. Be especially careful when using combination (pre-mixed) products, which may include fungicides subject to resistance prevention strategies. Tables 20-22 list fungicide materials along with their corresponding FRAC codes for ease of reference.

Guidelines to prevent or delay resistance to turf fungicides 


Minimize disease conditions

  • Employ good cultural practices.
  • Choose resistant turfgrass cultivars or species.

Make proper fungicide choices

  • Be sure of the problem.
  • Decide if it warrants treatment.
  • Read the label, calibrate, and apply properly.

Know the material

  • Read the label to determine the active ingredient.
  • Is repeated use likely to lead to resistance (i.e. does it have a single-site mode-of-action)?
  • Determine the fungicide group to which it belongs.
  • Mix or alternate between fungicide groups with single-site mode-of-action or with contact/protectant fungicides. Do not use fungicides with the same FRAC (Fungicide Resistance Action Committee) code number in combination or rotation.
  • Make sure all pesticides being applied in tank-mixtures are compatible prior to mixing.

Table 20. Chemical classes, trade names and topical modes of action of fungicides registered for use on turf.

Common Name FRAC 1 Group Name Trade Name(s) Topical mode of action 2

azoxystrobin

11

Strobilurin (QoI)

Heritage (50WG, TL, G)

Acropetal Penetrant

boscalid

7

Succinate Dehydrogenase Inhibitor

Emerald 70EG

Acropetal Penetrant

captan

M4

Phthamlimides

Captan (50W, 50WP, 4L), Captec 4L

Contact

chloroneb

14

Aromatic Hydrocarbon

Terraneb SP, Teremec SP, Andersons Fungicide V, Proturf Fungicide V

Contact

chlorothalonil 3

M5

Chloronitrile

Andersons 5% Daconil 5G, ArmorTech (825 DF, CLT 720), Concorde SST 6F, Daconil (5G, 2787, Zn, Ultrex, WeatherStik), Echo 720F, Ensign 720, Equus 500ZN, Manicure (6FL, Ultra), Lebanon Daconil 5G, Legend, Pegasus (6L, DFX, HPX)

Contact

cyazofamid

21

Quinone inside Inhibitors (QiI)

Segway

Localized Penetrant

etridiazol (ethazole)

14

Aromatic Hydrocarbon

Koban, Terrazole 35WP, Truban

Contact

fluazinam

29

Uncoupler of oxidative phosphorylation

Secure

Contact

fludioxonil

12

Phenylpyrrole

Medallion (WDG, WP)

Contact

fluoxastrobin

11

Strobilurin (QoI)

Fame 480SC

Acropetal Penetrant

flutolanil

7

Succinate Dehydrogenase Inhibitor

ProStar 70WP, Moncut 70-DF

Acropetal Penetrant

fluxapyroxad

7

Succinate Dehydrogenase Inhibitor

Xzemplar

Acropetal Penetrant

fosetyl-Al (Aluminum tris)

33

Phosphonate

Autograph, Chipco Aliette, Chipco Signature, Chipco Signature Xtra, Lesco Prodigy Signature, Viceroy 70DF

Systemic Penetrant

iprodione

2

Dicarboximide

Andersons Fungicide X, ArmorTech IP 233, Chipco 26 GT, Chipco 26019, Iprodione Pro, Lesco 18 Plus, Proturf Fungicide X, Raven

Localized Penetrant

isofetamid

7

Succinate Dehydrogenase Inhibitor

Kabuto

Acropetal Penetrant

mancozeb

M3

Dithiocarbamate

Dithane 75DF, Fore Rainshield 80WP, Junction, Lesco Mancozeb DG, Lesco 4 Flowable Mancozeb, Manzate Pro-Stick 200, Protect DF, WingMan (4L, DF)

Contact

mandestrobin

11

Strobilurin (QoI)

Pinpoint

Acropetal Penetrant

maneb

M3

Dithiocarbamate

Maneb 80WP, Maneb 75DF, Pentathalon (LF, DF)

Contact

mefenoxam

4

Phenylamide

Andersons Pythium Control, Mefanoxam, Subdue MAXX

Acropetal Penetrant

metalaxyl

4

Phenylamide

Subdue 2E, Subdue GR, Subdue WSP, Apron (seed treatment), Vireo MEC

Acropetal Penetrant

metconazole

3

Demethylation Inhibitor

Tourney

Acropetal Penetrant

myclobutanil

3

Demethylation Inhibitor

Andersons Golden Eagle, Eagle 20EW, Siskin

Acropetal Penetrant

PCNB (pentachloronitrobenzene or quintozene)

14

Aromatic Hydrocarbon

Andersons FFII 15.4G, Defend 4F, Engage 75W, Fluid Fungicide II, Lesco Revere 4000 4F (10G), Parflo 4F, PCNB 12.5G, Penstar 75WP, Terraclor 400F (75WP), Turfcide 400F (10G)

Contact

penthiopyrad

7

Succinate Dehydrogenase Inhibitor

Velista

Acropetal Penetrant

phosphite (salts)

33

Phosphonate

Appear, Alude 5.2F, Biophos, Fiata Stessguard, Fosphite, Jetphiter, Magellan, Phostrol, Reliant, ReSyst 5F, Vital 4L

Systemic Penetrant

polyoxin D zinc salt

19

Polyoxin

Endorse 2.5WP, Affirm 11.3WDG

Localized Penetrant

propamocarb

28

Carbamate

Banol 6S

Localized Penetrant

propiconazole

3

Demethylation Inhibitor

ArmorTech PPZ 143, Banner GL, Banner MAXX II, Kestrel, Lesco Spectator, Procon-Z, ProPensity, Propiconazole Pro 1.3MEC, PropiMax, Strider

Acropetal Penetrant

pyraclostrobin

11

Strobilurin (QoI)

Insignia Intrinsic SC, Insignia

Localized Penetrant

tebuconazole

3

Demethylation Inhibitor

Clearscape, Mirage Stressguard, Tebuconazole 3.6F, Torque, Skylark,

Acropetal Penetrant

thiophanate-methyl

1

Benzimidazole

Allban, Andersons Systemic Fungicide 2.3G, ArmorTech TM 462, Cleary's 3336 (F, WP, DG lite, G, GC, Pro-Pak, Plus), Fungo (Flo, 50WSB), Lesco T-Storm 2G, Systec, T-Bird (4.5L, WDG), Tee-Off 4.5F, T-Methyl SPC 50 WSB, TM (4, SF, 85WDG)

Acropetal Penetrant

thiram

M3

Dithiocarbamate

Defiant 75WDG, Thiram, Spotrete F

Contact

triadimefon

3

Demethylation Inhibitor

Accost 1G, Bayleton (50WSP, Flo), Andersons Fungicide VII 0.59G, Andersons 1% Bayleton 1G, Lebanon Bayleton 1G

Acropetal Penetrant

trifloxystrobin

11

Strobilurin (QoI)

Compass 50WDG

Localized Penetrant

triticonazole 5

3

Demethylation Inhibitor

Trinity, Chipco Triton (70WDG, Flo)

Acropetal Penetrant

vinclozolin

2

Dicarboximide

Curalan 4F, Touché EG

Localized Penetrant

1 Fungicide Resistance Action Committee (FRAC) Code: fungicides with the same FRAC code have the same mode of action. M-codes indicate multi-site chemicals with low risk of resistance development. It is recommended to rotate applications by FRAC code and not to make sequential applications of fungicides with the same FRAC code.

2 See above text for information on topical mode of action.
3 Use of chlorothalonil is regulated in Massachusetts under the Public Drinking Water Supply protection regulations, see the Pesticide Regulations section of this guide for details.
Phosphite (salts) is also commonly referred to as phosphorus acid or phosphonate.
5 Use of triticonazole is regulated in Massachusetts under the Public Drinking Water Supply protection regulations, see the Pesticide Regulations section of this guide for details.

Updated October 2017

Table 21. Pre-mixed fungicide products registered for use on turf.

Pre-mixed Products (Common Name) FRAC 1 Trade Name(s)

azoxystrobin + chlorothalonil 2

11 + M5

Renown

azoxystrobin + difenconazole

11 + 3

Briskway

azoxystrobin + propiconazole

11 + 3

Headway, Headway G, Contend B

Benzovindulflupyr + difenconazole

3 + 7

Contend A

chlorothalonil 2 + acibenzolar-S-methyl

M5 + P1

Daconil Action

chlorothalonil 2 + propiconazole

M5 + 3

Concert II, Echo Propiconazole Turf Fungicide

chlorothalonil 2 + tebuconazole

M5 + 3

E-Scape ETQ

chlorothalonil 2+ thiophanate-methyl

M5 + 1

Broadside, ConSyst, Peregrine, TM/C WDG, Spectro

chlorothalonil 2 + fludioxonil + propiconazole

M5 + 12 + 3

Instrata

chlorothalonil 2 + iprodione + tebuconazole + thiophanate-methyl

M5 + 3 + 3 + 1

Enclave

fluoxastrobin + chlorothalonil 2

11 + M5

Fame C

fluoxastrobin + tebuconazole

11 + 3

Fame T

fluopyram + trifloxystrobin

7 +11

Exteris

iprodione + trifloxystrobin

2 + 11

Interface Stressguard

mancozeb + copper hydroxide

M3 + M1

Junction

mancozeb + myclobutanil

M3 + 3

MANhandle

propamocarb + fluopicolide

28 + 43

Stellar

pyraclostrobin + boscalid

11 + 7

Honor

pyraclostrobin + fluxapyroxad

11 + 7

Lexicon

pyraclostrobin + triticonazole 3

11 + 3

Pillar G Intrinsic

thiophanate-methyl + chloroneb

1 + 14

Proturf Fungicide IX

thiophanate-methyl + flutolanil

1 + 7

SysStar

thiophanate-methyl + iprodione

1 + 2

ArmorTech TMI 20/20, 26/36 Fungicide, Dovetail, Lesco Twosome, Proturf Fluid Fungicide

thiophanate-methyl + mancozeb

1 + M3

Duosan (WP, WSB)

triadimefon + flutolanil

3 + 7

Prostar Plus

triadimefon + trifloxystrobin

3 + 11

Armada

triadimefon + trifloxystrobin + stress guard

3 + 11

Tartan Stressguard

1 Fungicide Resistance Action Committee (FRAC) Code: fungicides with the same FRAC code have the same mode of action. M-codes indicate multi-site chemicals with low risk of resistance development. It is recommended to rotate applications by FRAC code and not to make sequential applications of fungicides with the same FRAC code.

2 Use of chlorothalonil is regulated in Massachusetts under the Public Drinking Water Supply protection regulation, see the Pesticide Regulations section of this guide for details.

3 Use of triticonazole is regulated in Massachusetts under the Public Drinking Water Supply protection regulations, see the Pesticide Regulations section of this guide for details.

Updated October 2017

Disease management with fungicides

To get the most from a fungicide application within an IPM program, it is important to proceed in an informed and intelligent manner. Keep in mind that fungal pathogens of plants are dependent on a susceptible host and specific, favorable environmental conditions in order to cause disease. Planting resistant turfgrass cultivars (see Turfgrass Selection: Species and Cultivars) and modifying the growing environment to help reduce disease will make fungicides more effective. The most important aspect of disease control is correct identification of your target pest. It is imperative to be certain of the identity of the pathogen prior to any fungicide application. If in doubt, send a turf sample to the UMass Extension Plant Diagnostic Lab (ag.umass.edu/services/plant-diagnostics-laboratory). Knowing the pathogen allows you to know which grass species are susceptible or resistant, the optimum conditions for disease development, and the sensitivity of the pathogen to specific fungicides.

If you experience reduced efficacy or complete failure from fungicide applications to control dollar spot and athracnose, the UMass Pathology Lab offers both in vitro and molecular assays to assess potential fungicide resistance in the disease population.  See the Fungicide Resistance Assay page of this web site for information.

Table 22. Commonly used turf fungicides and the diseases they are labeled to control or suppress.

Click to download Table 22

Section 6: Nematode Management

In this section:

Understanding nematode populations

In the Northeastern United States, high populations of nematodes in turf areas are generally restricted to golf greens as opposed to golf fairways, athletic fields, and lawn areas. Golf greens provide an ideal environment for nematodes. Root zones are commonly 75% to 95% sand which provides ideal pore spaces for oxygen, water and nematode mobility, and greens are watered frequently. Plant parasitic nematodes are found in all soils where plants grow but damage does not occur unless high populations develop. Golf greens can support high nematode populations and damage is exacerbated by other stresses brought about by environmental conditions, cultural practices and play.

Nematodes injure turfgrass roots either by feeding or burrowing through tissues. Depending on the host and the nematode involved, symptoms on roots include: inhibition of root elongation, swollen tips, galls, lesions, and shortened stubby roots. In most cases root symptoms are not obvious. Symptoms occurring above-ground result from root dysfunction and are not unique to nematodes. Patchy areas of wilting, thinning and decline occur where nematode populations are excessively high. Lance nematodes can result in patches of dead grass similar to fungal patch diseases. Above-ground symptoms are of little value in diagnosing nematode problems in turf. An accurate assessment of the pathogenic potential of nematodes can only be determined by a nematode assay.

Extraction of nematodes from soil is an imperfect process and only provides an estimation of the total population. Repeated extractions from the same soil sample will yield different results. It is not important exactly how many nematodes are recovered from the soil. Populations above thresholds are potentially a problem, while low populations are not. Moderate to high populations of nematodes should be considered within the context of other stresses and diseases present at the time.

Nematode population distribution

Nematodes are unequally distributed in the soil both vertically and horizontally. In the horizontal plane, nematodes have a clumped distribution. Figure 3 shows the number of nematodes in individual soil cores taken at one foot intervals in a transect across a putting green. The average number of nematodes in the example is 51. With regard to vertical distribution, population densities of various species differ according to the depth at which the sample was taken. Some tend to be concentrated in the upper portion of the soil profile. For example, a sample taken at a 2” depth may have twice the concentration of stunt nematodes as the same sample taken at 4”. Other nematodes may be more evenly distributed through the 4” depth.

Time of year

During winter months nematode populations decline. As the turf resumes growth, nematodes begin feeding. The reproductive potential of nematodes increases as the soil temperature rises. In Massachusetts, populations peak anytime from mid-June through mid- to late July. An additional peak of activity may occur later in the season.

For More Information
For further information about turf nematode assays and assay fees, refer to the UMass Extension Plant Diagnostic Lab at ag.umass.edu/services/plant-diagnostics-laboratory.

Assay procedure

It is not possible to extract all of the nematodes from a soil sample. Also, extraction techniques vary from one laboratory to another and some techniques are more efficient than others for recovering certain species.

Collecting a soil sample

Nematode populations are estimated most accurately with a composite sample. Use a 3/4” to 1” diameter soil probe, or something similar, and sample to a depth of 3 to 4” throughout the site. If a patch of dead turf is present, take 6 or 7 cores from within the patch, and for comparison, take 8 to 10 cores in a circle about 1 foot from the damage.

When damage is evident, collect 20 to 25 subsamples from throughout the affected area and bulk them. For comparison, a composite sample should also be taken from an adjacent, healthy appearing area.

When no damage is evident the entire green can be sampled by collecting 15 to 20 samples and bulking them as one. However, if the same green is sampled again, the assay results may be different solely because of the unequal distribution of nematodes. Also, there may be “hot spots” were nematode populations are high. When the intention is to monitor nematode populations over the course of the year, or from season to season, choose an area no larger than 500 sq. ft. Return to the same area later for additional samples. Collect 15 to 20 cores from within the designated area and bulk them.

The soil (at least one-half pint) should be placed in a container, such as a plastic bag, to prevent desiccation. Clearly identify the sample number on the outside of the container. After collection, refrigerate or deliver to The UMass Extension Plant Diagnostic Lab as soon as possible (ag.umass.edu/services/plant-diagnostics-laboratory).

Figure 3. Horizontal distribution of nematodes in a sample putting green
Golf greens provide an ideal environment for nematodes. Root zones are commonly 75% to 95% sand which provides ideal pore spaces for oxygen, water and nematode mobility.

Important note

Due to fluctuations in population levels over the course of the season, a single-sample evaluation for nematodes can be misleading, particularly if the results indicate populations below “threshold levels.” A more comprehensive evaluation the following year is recommended as a follow-up. Collect samples as outlined above starting in early June and re-sampling every four to five weeks until mid- to late September.

Nematode threshold levels

Threshold levels (nematode population levels which justify the implementation of control measures) are dependent on the variables described above. At this time there is very little experimental data to establish threshold levels for golf greens in Massachusetts and New England. The numbers listed in Table 23 are based on research from other states as well as from case history information and survey results compiled in our region. These numbers are meant to serve as a guide only and are subject to change.

Table 23. Guide to approximate threshold levels for nematodes in turf for the Northeast.

Nematode No. / 100cc soil *
needle 100
lance 400
stunt 800
spiral 1,500
ring 1,500
lesion 100
cyst juveniles 500
root-knot juveniles 500
stubby root 100
sting 20

* Note: These threshold levels were developed when a nematicide capable of stopping nematode populations from developing further was commercially available. The thresholds listed here are not meant to imply that damage would occur at these levels. Some stress may occur at these levels, but at 2x or 3x these numbers damage would likely be evident.

Assessing damage caused by nematodes

High populations of certain species of nematodes may indicate that the root system has become debilitated to a significant extent. However, this information should be evaluated in context with past and prevailing circumstances. For example, all of the following factors are important in the development of a diagnosis and recommendation: species and numbers of nematodes present; depth at which the sample was taken; turfgrass species composition; depth of root system; soil texture; symptoms and extent of damage; potential contamination of the environment by a nematicide; and presence of other stresses to turf.

Use of nematicides

The decision to use nematicides must be carefully evaluated. The simple presence of plant parasitic nematodes does not warrant chemical application. Furthermore, when high populations of nematodes occur in the absence of appreciable damage to turf, it is difficult to justify applications. Nematicides should not be used where contamination of water may occur.

Fenamiphos (Nemacur), the only nematicide both effective on and labeled for control of nematodes on tees and greens, is a restricted use material. In addition, it is one of the pesticides on the Massachusetts Groundwater Protection List. Fenamiphos is being phased out of the market and existing stocks can be used only until October 6, 2017. Turf managers who wish to apply this material should refer to the Pesticide Regulations section of this guide.

Alternatives to nematicides

There currently are no cultural practices that will significantly reduce nematode populations. Any practices that encourage root growth and increase plant health, however, will help turf tolerate nematodes. Several biological controls and other “novel products” are available; however, field trials of these products have not been promising.

Section 7: Pesticide Regulations

Massachusetts regulations overview

The Federal Government regulates pesticides through the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). FIFRA empowers the Environmental Protection Agency (EPA) to register pesticides and to regulate their use. FIFRA also allows for individual states to have primary enforcement responsibility for pesticide use within their borders

The Massachusetts Department of Agricultural Resources (MDAR) Pesticide Program regulates the use of pesticides in this state according to the 1978 Massachusetts Pesticide Control Act (Chapter 132 B of the Mass. General Laws). State regulations 333 CMR 1.00-14.00 have been promulgated pursuant to this law.

A brief overview of the specific parts of the regulation governing the application of pesticides by turf managers and in some instances other pesticide applicators follows. It is incumbent upon pesticide applicators to become familiar with the details of all aspects of the Pesticide Regulations, not just those listed here. For additional information on pesticide regulations, contact the Massachusetts Department of Agricultural Resources Pesticide Program (see contact information in the side bar of this page).

To obtain a complete copy of the regulations, contact the MDAR Pesticide Program or the UMass Extension Pesticide Education Program. The regulations are also available for download at the MDAR Pesticide Program web site.

For More Information

UMass Extension Pesticide Education Program Agricultural Engineering Building University of Massachusetts Amherst, MA 01003 (413) 545-1044 www.umass.edu/pested

Massachusetts Department of Agricultural Resources Pesticide Program 251 Causeway Street, Suite 500 Boston, MA 02114-2151 (617) 626-1720 http://www.mass.gov/eea/agencies/agr/pesticides/

Licensing and certification

The process of licensing and certification for those individuals who apply pesticides is conducted by the MDAR Pesticide Program under Massachusetts Pesticide Regulations 333 CMR 10.00. Applicators applying pesticides to the property of another or areas to which the public has access, both indoors and outdoors, must be licensed. Applicators must be certified in order to buy restricted use pesticides. Complete information on the procedures and exams for licensing and certification, as well as recertification and insurance requirements are detailed in the Pesticide Examination and License Information Bulletin, available annually from the MDAR Pesticide Program.

The UMass Extension Pesticide Education Program conducts regular workshops and trainings designed to assist applicators in preparation for licensing and certification exams. Study materials are also available for purchase. For additional information on Massachusetts pesticide applicator licensing and training visit the Pesticide License Information page of this web site.

Notification and posting for turf pesticide applications to residential and public or private non-residential properties

333 CMR 13.06 requires turf pesticide applicators provide to the entity with which they contract or the manager or superintendent of the contracting entity information about pesticides used, safety measures for humans and the environment, and specific application information. Provisions for pre-notification of application are covered in this regulation. It further requires that turf pesticide applicators post approved signs on properties prior to treatment and that signs remain in place for 24-72 hours. Further information on this regulation should be obtained from the MDAR Pesticide Program.

Record keeping

Regulation 333 CMR 10.14 requires that all licensed and certified commercial applicators or their employers keep true and accurate operational records on each application of a pesticide. The same regulation authorizes the Massachusetts Department of Agricultural Resources to require annual records and reports of the information maintained in accordance with the regulation. Record keeping forms and/or a listing of specific information required is available from the MDAR Pesticide Program.

The Children & Families Protection Act

Legislation (The Act Protecting Children and Families from Harmful Pesticides — Chapter 85 of the Acts of 2000) that amends the Massachusetts Pesticide Control Act (Chapter 132B of the M.G.L.) took effect on November 1, 2000. This regulation is commonly known as the Children and Families Protection Act.

This legislation primarily addresses the use of pesticides in schools, day care centers, and school-age childcare programs. Other sections of the legislation include but are not limited to: notification and posting requirements, pesticide use along rights-of- way, applicator competency evaluation, and Integrated Pest Management (IPM) plans. Ultimately, the intent of the legislation is to encourage the use of IPM and to minimize pesticide exposure, especially to children and facility employees.

Who is responsible? Those persons who perform, contract, and/or administratively oversee pest management services for schools, day care centers, and school-age child care programs play significant roles in ensuring compliance regulation. Additional parties involved may include utility companies and state agencies.

The MDAR Pesticide Program is responsible for the implementation of this legislation. Detailed information about how to comply with the Children and Families Protection Act can be obtained from the MDAR Pesticide Program. For turf managers that must develop an IPM plan under the requirements of the Children and Families Protection Act, UMass Extension has published Integrated Pest Management Protocols for Turf on School Properties and Sports Fields. This manual is a tool that specifies the steps required for development and implementation of a comprehensive IPM plan. For additional information see the Printed Publications page of this web site.

Massachusetts Public Drinking Water Supply Protection Regulations

The Massachusetts Department of Agricultural Resources (MDAR) Public Drinking Water Supply Protection Regulations (State Regulation 333 CMR 12.00, enacted 1/1/1992) are intended to prevent non-point source contamination of public drinking water supply wells from pesticide products on the Massachusetts Groundwater Protection List. Updated annually, the Groundwater Protection List identifies specific pesticide active ingredients that could potentially impact groundwater due to their chemical characteristics and toxicological profile.

Geographic sites protected under the regulations are referred to as primary recharge areas. For pesticide regulatory purposes, a primary recharge area is considered to be either an Interim Wellhead Protection Area (IWPA) or a “Zone II” for wells that have pumping rates of over 100,000 gallons per day (gpd). The Drinking Water Supply Protection Regulations do not apply to wells that pump less than 100,000 gpd.

If a management decision has been made to use one of the pesticides listed on the Groundwater Protection List, then it is the responsibility of the applicator to be aware if the site is within an IWPA or Zone II area, and to act accordingly. For general guidelines about how to comply with the Massachusetts Public Drinking Water Supply Protection Regulations, consult the flowchart in Figure 4 below.

Table 24. Massachusetts Groundwater Protection List (current as of April 1, 2018)

Herbicides Insecticides Fungicides
Acetochlor
Acifluorfen
Alachlor
Aldicarb
Atrazine
Bentazon*
Bromacil
Cyanazine
Chlorthal-dimethyl (DCPA)
Dimethanamid*
Diuron
Flufenacet
Fluthiacet-methyl
MCPA*
Metolachlor
Metribuzin
PCP
Pronamide
Propazine
Simazine
Sulfentrazone*
Aldicarb
Carbofuran
Dinotefuran*
Disulfoton
Fonofos
Lindane
Methoxyfenozide
PCP
Propoxur
Terbufos
Thiamethoxam*
Chlorothalonil*
Cyflufenamid
Cyproconazole
Folpet
Kresoxim-methyl
Triticonazole*
Sedaxane
Nematicides
Fenamiphos*

* Denotes active ingredient labeled for cool-season turf use

Figure 4. Do the Massachusetts Public Drinking Water Supply Protection Regulations Apply to You? 


1. Do you plan to make a pesticide application within a Zone II or Interim Wellhead Protection Area (IWPA)?

For instructions on how to determine if your application will fall within a Zone II or an IWPA, contact the MDAR Pesticide Program at (617) 626-1771, or visit https://www.mass.gov/pesticides-and-water-supply-protection

If NO, then STOP. You do not need to be concerned about the regulations.

If YES, then proceed to Question 2.
 

2. Does the pesticide product that you intend to use contain any of the active ingredients listed on the current Massachusetts Groundwater Protection List?

If NO, then STOP. You do not need to be concerned about the regulations.

If YES, then proceed to question 3.
 

3. Are there any viable alternatives to the pesticide that you intend to use?

If YES,  then STOP and use the alternative.

If NO, then proceed to Question 4.
 

4. Will the pesticide product be applied to an area which has greater than 50% foliar cover?

If YES, then you must confirm the non-viability of alternatives, you must apply the pesticide as part of an Integrated Pest Management (IPM) program approved by MDAR, and you must submit a Groundwater Protection Program Notification Form to MDAR within 10 days of the end of the calendar month in which the pesticide is applied.

If NO (meaning that the pesticide product that you intend to use is soil-applied, or will be applied to an area with less than 50% foliar cover), then you must confirm the non-viability of alternatives, you must apply the pesticide as part of a MDAR approved Integrated Pest Management (IPM) program, and you must verify that a Pesticide Management Plan (PMP) for that use pattern has been approved by MDAR.
 

For further information on MDAR notification requirements, MDAR approved Integrated Pest Management (IPM) programs and/or a Pesticide Management Plan (PMP), contact the MDAR Pesticide Program at (617) 626-1771.

Turf pesticides on the Massachusetts Groundwater Protection List

Herbicides

Bentazon (Basagran) is used primarily for the control of yellow nutsedge in turf. Possible alternatives to bentazon include halosulfuron and mesotrione. For more information about bentazon, see the Characteristics of Turf Herbicides section of this guide.

Dimethanamid (Tower) is used primarily for the preemergence control of yellow nutsedge in turf.  No other material is currently labeled for preemergence yellow nutsedge control.  Postemergence control with halosulfuron or mesotrione is an alternative option.  For more information about dimethanamid, see the Characteristics of Turf Herbicides section of this guide.

MCPA (several trade names) is a component of several combination products labeled for postemergence control of broadleaf weeds in turf. MCPP has gained favor over MCPA for many formulations in recent years because of higher activity. Thus, viable alternatives are readily available. For more information about MCPA, see the Characteristics of Turf Herbicides section of this guide.

Sulfentrazone (several trade names) is used primarily for postemergence management of a range of broadleaf weeds in turf. It is formulated alone or in combination with additional herbicides. Possible alternatives to sulfentrazone include halosulfuron and mesotrione. See the Characteristics of Turf Herbicides section of this guide for additional information about sulfentrazone.

Fungicides

Chlorothalonil (Daconil and several other trade names) is labeled for use on several major turfgrass diseases in the Northeastern U.S, including anthracnose, brown patch, copper spot, dollar spot, Microdochium patch (pink snow mold), Helminthosporium leaf spot disease, red thread, rusts, and Typhula blight (gray or speckled snow mold). Many alternative fungicides are available for these diseases (see Table 22 in the Disease Management with Fungicides section of this guide). The primary disadvantage of many of the alternative compounds, however, is the potential for fungicide resistance development with repeated use. Because resistance has not been reported for chlorothalonil, it is an important rotation and tank-mix product for resistance management programs (refer to the Characteristics of Turf Fungicides section of this guide for a discussion of fungicide resistance). Also, the broad spectrum activity of chlorothalonil is part of its value as a fungicide. This value is reflected in the relatively frequent use of chlorothalonil on turf, despite decreased residual control compared to penetrant fungicides. Many of the alternative products do not have the same broad spectrum of activity.

Unfortunately, cultural management may not be sufficient to protect turf in stressful conditions, especially when weather conditions are conducive to the development of a particular disease, and in particular on golf greens and tees. In a good IPM program, no fungicide application should be considered for a specific disease problem without considering secondary problems. Before it is determined that use of an alternative to chlorothalonil will be a sound decision, it is necessary to consider all disease problems in an area and in a particular season. Often, determining a viable alternative is a complex task involving more than a single disease evaluation. At this time, there is no viable alternative to chlorothalonil plus a penetrant fungicide for control of anthracnose on putting greens. See Figure 5 for special considerations about the application of chlorothalonil for anthracnose in Massachusetts.

Figure 5. Guidelines for the use of chlorothalonil for anthracnose on putting greens in Massachusetts.

  • Obtain a diagnosis, at least once, from a diagnostic lab and keep the report in your records. Information for submitting samples to the UMass Extension Plant Diagnostic Lab can be found at ag.umass.edu/services/plant-diagnostics-laboratory.
     
  • File the Notification Form with MDAR within 10 days of the end of each calendar month in which chlorothalonil is applied (you also must record all applications of chlorothalonil on the IPM Program form listed below). The proper Notification Form can be obtained by contacting the MDAR Pesticide Program at (617) 626-1720 or visiting http://www.mass.gov/eea/agencies/agr/pesticides/.
     
  • Obtain a copy of the UMass Extension fact sheet “Why is it so Difficult to Control Anthracnose?” The fact sheet is available on the MDAR web site or on the UMass Extension Turf Program web site at ag.umass.edu/turf/fact-sheets/why-is-it-so-difficult-to-control-anthracnose.
     
Manage anthracnose using the MDAR approved Turf Anthracnose Management Approved IPM Program and maintain the required records with your pesticide application records. A copy of the program can be obtained by contacting the MDAR Pesticide Program at (617) 626-1720 or visiting http://www.mass.gov/eea/agencies/agr/pesticides/.

Triticonazole (Trinity, Triton) provides good control of a number of turf diseases including anthracnose, dollar spot, necrotic ring spot, red thread, brown patch, and take-all patch. Triticonazole is one of the demethylation inhibitor (DMI) fungicides. If you make a decision to use triticonazole, but are located in a Zone II or IWPA area, several alternatives in the DMI class are available. Alternatives include propiconazole, fenarimol, metconazole, triadimefon, and myclobutanil. Refer to Table 22 in the Disease Management with Fungicides section of this guide for additional information.

Insecticides

Dinotefuran (Zylam) is one of several insecticide compounds in the neonicotinoid class. While it is used more commonly in landscape settings, it is now being marketed for control of annual bluegrass weevils on golf courses. If you wish to control ABW in a Zone II or IWPA area, there are several alternatives to dinotefuran.  These include a pyrethroid to target adults; or indoxacarb, spinosad, chlorantraniliprole, or trichlorfon to target larvae.

Thiamethoxam (Meridian) is another insecticide in the neonicotinoid class. Insects on the label include annual bluegrass weevil, black turfgrass ataenius, caterpillars, billbugs, and white grubs. If you wish to make an application for any of these target insects in a Zone II or IWPA area, you should be able to substitute another neonicotinoid. For example, imidacloprid or chlothianidin are viable alternatives and are both somewhat less soluble than thiamethoxam. If the primary target is white grubs, chlorantraniliprole would also be an alternative. See the Insect Management with Insecticides section of this guide for additional information.

Nematicides

Fenamiphos (Nemacur) is a nematicide and is labeled for use on golf course greens (bentgrass) where virtually all nematode problems on turf occur. Fenamiphos has been gradually phased out of the turf market, but any existing stocks can still be used until October 6, 2017. As such, fenamiphos is a highly toxic material and should be used only after high nematode populations have been confirmed by a diagnostic lab (for the UMass Extension Plant Diagnostic Lab, see ag.umass.edu/services/plant-diagnostics-laboratory).

Considerable testing underway at this time seeks to identify viable alternatives to fenamiphos, but an effective replacement has yet to be found. Cultural practices that encourage root system health and development are strongly recommended as a first line of defense against nematode pressure. Cultural management may help to mitigate damage from low nematode populations, but unfortunately may not be sufficient for golf greens with high populations.

Appendix A: Turf Pest Damage Monitoring Chart

This chart indicates when peak periods of damage are most likely to occur in the case of diseases and insects, and when seed will begin to germinate in the case of weeds. It is intended for use as a guide for monitoring pest activity and for pinpointing time periods when pest damage may occur. Please refer to the appropriate pest management sections of this guide for further information. This chart is not intended to indicate when applications of pesticides should be made, if at all.

Weeds J F M A M J J A S O N D Comments
General Weed Scouting Period                                                 Most weeds are large enough for easy identification.
Crabgrass and other Annual Grasses                                                 Period of peak germination.  Germination begins in spring when average soil temperature is 55°F for one week.
Annual Bluegrass                                                 Period of peak germination. May develop seed heads earlier in season if weather is favorable.
Yellow Nutsedge                                                 Sedges have triangular, solid stems, in contrast to the round, hollow stems of grasses.
Winter Annual Broadleaves                                                 Period of peak germination.
Summer Annual Broadleaves                                                 Period of peak germination.
Perennial Broadleaves                                                 Period of peak germination.

 

Insects J F M A M J J A S O N D Comments
White Grubs                                                 Turf appears to suffer drought stress. Skunks, raccoons, or birds may tear up the turf. Turf may pull up “carpet like.”
Ants                                                 Mounds in turf. Mound activity begins in mid-April to mid-May.
Billbugs                                                 Areas wilt and do not respond to watering. Sawdust-like material in thatch. Turf is easily tugged loose. Adults active in late May – mid June.
Chinch Bugs                                                 Wilted or browned areas, most severe in sunny or sandy areas.
Cutworms                                                 Burrows surrounded by brown patches, green frass may be present.
Annual Bluegrass (Hyperodes) Weevil                                                 Yellow patches begin at edges of turf areas. Damaged areas may appear water soaked. Usually two generations per year.
Sod Webworm                                                 Discrete browned areas which coalesce later. Most common in sunny areas. May cause damage in late spring.

 

Diseases that cause irregular damage J F M A M J J A S O N D Comments
Algae, Mosses                                                 Algae: irregularly thinning turf, soil surface with has green or black coating that is slimy to the touch. Mosses: irregularly thinning turf, soil surface with has a thick, silvery green mat.
Bentgrass Dead Spot                                                 Circular patches (1”-2”). Tan dead tissues with reddish-brown borders on young, sand-based bentgrass putting greens.
Brown Ring Patch (Waitea Patch)                                                 Yellow, irregular rings or arcs
Copper Spot                                                 Small, copper or salmon colored circular spots less than 3” in diameter.
Damping-Off, Seed Rot                                                 Poor germination and dying or dead young seedlings.
Gray Leaf Spot                                                 Gray to brown leaf spots with black margin and yellow halo. Can coalesce to irregular patterns and complete blight.
Leaf Smuts                                                 Gray to black streaks of black powdery spores on leaves. Usually in turf three or more years old.
Leaf Spots and Blights/Melting Out                                                 Oval or eye-shaped, dark bordered spots; dark specks (fruiting bodies) may be present in older diseased tissue.
Powdery Mildew                                                 White to powdery gray mold on leaf surfaces, often found in shade. No leaf spots present.
Red Thread/Pink Patch                                                 Pink-red, often gelatinous mycelium on leaves when moist.  Tiny pink cotton candy-like puffs of spores.
Rusts                                                 Irregular pattern of bright orange, yellow, reddish-brown pustules on the grass blades. Powdery orange spores.
Slime Molds                                                 Slimy, superficially whitish-gray to yellow fungus, turning powdery later.

 

Diseases that cause Circular damage J F M A M J J A S O N D Comments
Anthracnose (Crown/Basal Rot)                                                 Leaves yellow and wilt, tiny black spiny fungal hairs in tufts may be visible by hand lens.
Brown Patch                                                 1’-3’ patches of light brown grass. Gray to white (smoke ring) mycelium at edge of patch may be present in moist conditions.
Dollar Spot                                                 Straw-colored silver dollar-sized spots. Leaf bands with brown or reddish-brown borders. White mycelium when wet.
Downy Mildew (Yellow Tuft)                                                 Yellow patches or tufts < 1” across. Plants easily pulled from turf.
Fairy Ring                                                 Rings or arcs up to 15’ across often with outer ring of dark green grass. Mushrooms may be present in ring.
Microdochium Patch) (Pink Snow Mold)                                                 Small orange brown to tan spots. Under humid conditions white to pink mycelium at margins.
Necrotic Ring Spot                                                 Patches, rings, “frog eyes” approx. 6”- 8” across, enlarging later. Common in Kentucky bluegrass.
Pythium Blight                                                 Circular pattern with tan spots, lacking dark borders on the leaves. Leaves matted and slimy with dense white mycelium.
Pythium Root Dysfunction                                                 Circular or irregular patches slowly wilt due to affected roots. Often found following sand topdressing or on recently-constructed sand-based putting greens
Pythium Root Rot                                                 Turf wilted, killed, or rotted. Often in poorly drained areas.
Summer Patch                                                 Circular patches or rings of straw-colored grass 6”- 8” across. Center may be green. Common in annual bluegrass.
Take-All Patch                                                 Yellow turning reddish, then brown, and later sunken patches occur. Centers often invaded by weeds. Common in bentgrass.
Typhula Blight (Gray or Speckled Snow Mold)                                                 Matted grass covered with white-gray mycelium. Small reddish, brown, or yellow sclerotia present.
Yellow Patch (Cool Weather Brown Patch)                                                 Yellow to straw-colored grass often sunken in high cut areas.

Appendix B: Calendar for Cultural Practices and Related Activities

This chart summarizes when turf management practices are most effective as to timing of fertilization, mowing, irrigation, liming, soil testing, cultivation, and planting activities. These dates are only approximate guidelines and are not intended to indicate absolute start and end dates for all regions of Massachusetts. Consult the appropriate pest sections in this guide for cultural practices recommended for pest management.

Weeds J F M A M J J A S O N D Comments
Cultivation
(aerification, dethatching)
                                                Practice during peak shoot growth; terminate 2 weeks before low or high temperature stress.  Fall cultivation is often preferable due to annual grass weed pressure in spring.
Fertilization                                                 If 1 time per year, apply in early fall. If 2 times per year, apply in spring and early fall. If 3 times per year, apply in early spring, late spring/early summer, and early fall.
Irrigation                                                 Irrigate at leaf roll/fold (mild stress), avoid over-watering.
Liming                                                 Apply any time the ground is not frozen, effective with aerification. Use caution later in the season as fall liming can increase Microdochium patch.
Mowing                                                 Continue to mow using the 1/3 rule until shoot growth ceases.
Planting (seeding, over-seeding)                                                 Late summer - early fall plantings are preferred, followed by spring. Avoid early summer and mid-summer plantings.
Soil testing                                                 Sample anytime the ground is not frozen; avoid recently fertilized and limed areas.

 

Appendix C: Useful Information

In the event of accidental poisoning, contact:

1-800-222-1222
(emergency hotline)
The Regional Center for Poison Control and Prevention
Boston Children’s Hospital
300 Longwood Avenue
Boston, MA 02115

Administrative phone: 1-617-335-6607

For emergency spill, fire, leak, or explosion:

1-800-262-8200
Chemtrec® 24-hour HAZMAT Emergency Communications Center
http://www.chemtrec.com

1-800-424-8802
National Response System (NRS)
http://www.nrc.uscg.mil/

For pesticide information:

National Pesticide Information Center (NPIC)
1-800-858-7378
http://www.npic.orst.edu

EXTOXNET
The Extension Toxicology Network
http://extoxnet.orst.edu

Greenbook®
http://www.greenbook.net

Crop Data Management Systems, Inc. (CDMS)
http://www.cdms.net