Hort Notes 2018 Vol. 29:12

A monthly e-newsletter from UMass Extension for landscapers, arborists, and other Green Industry professionals.

To read individual sections of the message, click on the section headings below to expand the content:

Hot Topics

Thank your clients with a 2019 UMass Garden Calendar!

Cost: $14, with a bulk rate available for quantities of 10 or more.

Gardening is enjoyed by so many people — it can ease stress, keep you limber, and even improve your mood! To help keep your plants healthy, productive, and beautiful, the 2019 UMass Garden Calendar offers helpful guidelines, daily tips, and an inspiring garden image each month!

For many years, UMass Extension has worked with the citizens of Massachusetts to help them make sound choices about growing, planting and maintaining plants in their landscapes, including vegetables, backyard fruits, and ornamental plants. Our 2019 calendar continues UMass Extension’s tradition of providing gardeners with useful information. This year’s calendar features the use of tomography to identify internal decay in mature trees that do not yet show any visible symptoms of damage, making it difficult to assess their potential risk in urban and suburban settings.

Each Month Features

• An inspiring garden image
• Daily gardening tips for Northeast growing conditions
• Daily sunrise and sunset times
• Phases of the moon
• Plenty of room for notes
• Low gloss paper for easy writing

ORDER ONLINE at www.umassgardencalendar.org

 

Questions & Answers

Q. I have heard of the idea of a late fall fertilizer application for turf… should I consider incorporating a late fall application into my fertilizer program?

Some more sophisticated turf management programs do include what is referred to as a late fall (or late season) fertilizer application.  The concept is to provide a last round of nutrient resources to help enhance both winter hardiness and spring recovery.  Correct timing, which is the brief window just after shoot growth has stopped but before the turf has lost green color, has to be spot on in order to realize benefits and prevent net harm.  Incorrect timing can stimulate turf into undesirable growth immediately prior to the onset of low temperature stress, and/or increase the potential for nutrients to move off-site with leaching or runoff.  For these reasons, late fall fertilization is more appropriate for intensively managed, high value turf areas (e.g. golf courses and sports fields) and is normally not warranted for lawns or grounds.  Late season fertilization should also be avoided in areas that are or may be environmentally sensitive, to further reduce the potential for negative environmental impact.

Q. I’m concerned about woody foundation plants under my care with regard to winter–related injury… is there anything that can be done to reduce the possibility of damage?

The first line of defense against damage from snow and ice loads is proper pruning practices.  Regular and informed pruning that encourages good branch structure is the first line of defense against damage from snow and ice loads. 

Folks often ask whether it is prudent to physically remove accumulated ice and snow, and the answer is that it depends.  When weather conditions are conducive to snow being easily dislodged, branches can be lifted, tapped, or gently shaken to allow the snow to fall off.  When it is colder and snow and ice are stubbornly attached, however, it is best to let things be, as the vigorous shaking or brushing required carries a much greater potential to cause the very breakage and injury that it is the goal to avoid in the first place.

For some relevant tips… structural protection (e.g. wooden shelters) should be considered for valuable shrubs, especially those that may be subject to snow falling from roof tops.  Burlap is useful for protecting both broadleaf evergreens from the effect of extreme cold, and salt-sensitive plants from salt spray.  Hardware cloth can be placed around the trunk of shrubs to deter chewing by voles and other rodents during the winter season.

Q. Is dormant seeding an effective avenue for turf establishment?

Dormant seeding is the planting of turfgrass seed after temperatures fall below the range in which seeds germinate (< 40-45° F). Unlike seeding that occurs during a more favorable time period, the idea is not to have the seed germinate rapidly, but instead sit ‘dormant’ throughout the winter until rising temperatures stimulate germination in the spring. The party line on dormant seeding is that it is never as effective as an ideal late summer seeding, and may or may not be as effective as waiting to seed in the spring. Some pros of dormant seeding include soils that are drier and easier to prepare relative to spring, a reduced need for irrigation and weed control attention in the period after planting, and the fact that plants can emerge as early as possible in the spring and get the jump on annual weed pressure. Cons of dormant seeding include mid-winter warm ups that promote germination too early, risk of seeds desiccating and drying out due to dry winter conditions, and the need for higher seeding rates (50% higher or more) compared to conventional seeding. Slower-establishing species such as Kentucky bluegrass are better suited to dormant seeding, as they are less likely to germinate in response to winter temperature fluctuations.

Dormant seeding is a gamble, but if resources are available and you are comfortable with the possibility of project failure, it is possible to come out ahead of the game come spring.

Jason D. Lanier, UMass Extension Greenhouse & Floriculture and Turf Management Programs

Trouble Maker of the Month

Spotted Lanternfly, Ticks, and Tick-Associated Disease! 

Plant of the Month

Cornus sericea, Red twig dogwood

December in the landscape can be gloomy as many plants have gone dormant. The red and yellow stems of Cornus sericea can provide some much needed color to the winter landscape. Cornus sericea is large, multi-stemmed shrub with a round to spreading, open habit; commonly growing 6-10’ tall and wide if not pruned. Its common name, red twig dogwood, comes from the vibrant red winter stems. The species has a suckering habit; however, cultivars do not sucker as heavily, making them better options for the landscape. 

The flat clusters of small, white flowers are present in late May to early June. Leaves are medium to dark green 2-5” long and 1-2.5” wide. Fall color can be variable, but is usually a nice mix of red and purple. Fruits are white to pale blue berries and appear in August and September. Fruit is commonly eaten by birds. Removing 1/4-1/3 of the oldest stems in early spring helps to promote growth of new stems, which have the best color. Stems are most effective in the winter. 

Native to eastern North America, Cornus sericea’s natural habitat is in wet, swampy areas or along streams and ponds. Plants do best in full sun to part shade and are adaptable to many soils, but like moisture. Cornus sericea is susceptible to leaf and twig blights, canker, and spots. Related species include Cornus alba and Cornus sanguinea, which are also large multi-stemmed shrubs with red stems. 
There are many notable cultivars of value in the landscape:

• ‘Budd’s Yellow’ – yellowtwig dogwood rapidly growing to 5-8’; disease resistant leaves
• ‘Cardinal’ – rapid growing redtwig dogwood to 6-9’
• ‘Farrow’ Artic Fire – dwarf cultivar growing 3-4’ with bright red winter stems
• ‘Flaviramea’ – yellowtwig growing 5-6’ tall
• ‘Neil Z’ Pucker Up – compact cultivar growing 3-4’ with puckered leaves
• ‘Silver and Gold’ – yellowtwig with variegated foliage
• Cornus sanguinea ‘Midwinter Fire’ – yellow stems tipped with red; yellow fall color
• Cornus sanguinea ‘Cato’ Artic Sun – dwarf yellowtwig with red tips
• Cornus alba ‘Ivory Halo’ – compact cultivar with variegated foliage

 

Amanda Bayer, UMass Extension Sustainable Nursery and Landscapes Specialist

Upcoming Events

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Spotted Lanternfly Preparedness Conference

February 7, 2019 - 8:30 am to 3:30 pm
Location: Doubletree Hotel, Milford MA

The spotted lanternfly (Lycorma delicatula) was first detected in the United States in Pennsylvania in 2014. This non-native, invasive insect has since had a large impact on agricultural and ornamental crops and the quality of life of many Pennsylvania residents. While this insect is associated with the invasive tree of heaven (Ailanthus altissima), it has been reported from 70+ species of host plants, including apple, plum, peach, grape, and many native and ornamental trees and shrubs. This insect is unfortunately on the move, having been detected in additional states including Delaware, New York, Virginia, New Jersey, Connecticut, and Maryland.

What can we do in Massachusetts to prepare for this insect? Knowledge is power. This conference will provide the latest research and information about the identification, life cycle, impact, monitoring, and Integrated Pest Management options that are known for this insect. Landscapers, arborists, tree wardens, foresters, nursery operators, lawn care professionals, grounds managers, and tree fruit and small fruit growers are encouraged to attend. Join UMass Extension in learning more about the spotted lanternfly!  6 pesticide contact hours for categories 25, 27, 29, 35, 36, and Applicators License.

 

For complete information, including the schedule and registration information, go to http://ag.umass.edu/landscape/events/spotted-lanternfly-preparedness-conference

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Other Upcoming Events:​

• 2/19: Principles and Fundamentals of Weed Science (part A1 of the Invasive Plant Certification series), Milford, MA
• 3/5: Community Tree Conference: Species Selection in the Urban Landscape - Professional Perspectives
• 3/14: State Regulations Pertaining to Invasive Plant Management (part A2 of the Invasive Plant Certification series), Milford, MA
• 3/19:  The Invasive Plant Issue and Invasive Plant Identification (part A3 of the Invasive Plant Certification series), Milford, MA
• 3/28:  Spring Kickoff: UMass Extension Landscape Education Day, Wareham, MA
• 4/9:  Developing an Invasive Plant Management Program (part B of the Invasive Plant Certification series), Milford, MA

For more information and registration for any of these events, go to the UMass Extension Landscape, Nursery, and Urban Forestry Program Upcoming Events Page. 

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Additional Resources

For detailed reports on growing conditions and pest activity – Check out the Landscape Message

For commercial growers of greenhouse crops and flowers - Check out the New England Greenhouse Update website

For professional turf managers - Check out Turf Management Updates

For home gardeners and garden retailers - Check out home lawn and garden resources. UMass Extension also has a Twitter feed that provides timely, daily gardening tips, sunrise and sunset times to home gardeners, see https://twitter.com/UMassGardenClip

Diagnostic Services

A UMass Laboratory Diagnoses Landscape and Turf Problems - The UMass Extension Plant Diagnostic Lab is available to serve commercial landscape contractors, turf managers, arborists, nurseries and other green industry professionals. It provides woody plant and turf disease analysis, woody plant and turf insect identification, turfgrass identification, weed identification, and offers a report of pest management strategies that are research based, economically sound and environmentally appropriate for the situation. Accurate diagnosis for a turf or landscape problem can often eliminate or reduce the need for pesticide use. For sampling procedures, detailed submission instructions and a list of fees, see Plant Diagnostics Laboratory

Soil and Plant Nutrient Testing - The University of Massachusetts Soil and Plant Nutrient Testing Laboratory is located on the campus of The University of Massachusetts at Amherst. Testing services are available to all. The function of the Soil and Plant Nutrient Testing Laboratory is to provide test results and recommendations that lead to the wise and economical use of soils and soil amendments. For complete information, visit the UMass Soil and Plant Nutrient Testing Laboratory web site.   Alternatively, call the lab at (413) 545-2311.