Landscape Message: September 20, 2024

UMass Extension's Landscape Message is an educational newsletter intended to inform and guide Massachusetts land care professionals in the management of our collective landscape. Detailed reports from scouts and Extension specialists on growing conditions, pest activity, and cultural practices for the management of woody ornamentals, trees, and turf are regular features. The following issue has been updated to provide timely management information and the latest regional news and environmental data. 

Welcome to Landscape Message #18 for the 2024 growing season.  We will now move to the monthly phase of the annual schedule, and the next message will be posted on Friday, October 18. To receive immediate notification when the next Landscape Message update is posted, be sure to join our e-mail list 

Click on the headings below to jump to that section of the message.

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In This Issue

Scouting Information by Region

Environmental Data

Phenology

Regional Notes

Woody Ornamentals

Diseases

Insects and Other Arthropods

Landscape Weeds

Additional Resources

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Scouting Information by Region

Environmental Data

The following data was collected on or about September 18, 2024. Total accumulated growing degree days (GDD) represent the heating units above a 50ºF baseline temperature collected via regional NEWA stations (http://newa.cornell.edu) for the 2024 calendar year. This information is intended for use as a guide for monitoring the developmental stages of pests in your location and planning management strategies accordingly.

MA Region/Location	2024 Growing Degree Days		Soil Temp (°F at 4" depth)		Precipitation (Gain in inches since last report)	Time/Date of Readings
	Gain since last report	2024 total	Sun	Shade
CAPE	213	2445	68	64	0.00	12:00 PM 9/18/2024
SOUTHEAST	205	2724	71	66	0.00	3:00 PM 9/18/2024
NORTH SHORE	204	2507	63	61	0.00	9:00 AM 9/18/2024
EAST	232	2752	68	63	0.02	4:00 PM 9/18/2024
METRO	209	2580	62	60	0.03	6:30 AM 9/18/2024
CENTRAL	224	2633	66	62	0.10	11:00 AM 9/18/2024
PIONEER VALLEY	233	2587	67	65	0.40	11:00 AM 9/18/2024
BERKSHIRES	161	2286	65	59	0.60	7:00 AM 9/18/2024
AVERAGE	210	2564	66	63	0.14	-
n/a = information not available

 

US Drought Monitor:  At this time, all of Essex and Suffok counties, small portions of both Norfolk and Essex counties, a large portion of the Cape, and all of Nantucket are classified as "D0 - Abnormally Dry" (about 14% of the state's area in total). State map as of Thursday 9/19: https://droughtmonitor.unl.edu/CurrentMap/StateDroughtMonitor.aspx?MA

Phenology

Indicator Plants - Stages of Flowering (BEGIN, BEGIN/FULL, FULL, FULL/END, END)
PLANT NAME (Botanic / Common)	CAPE	S.E.	N.S.	EAST	METRO W.	CENT.	P.V.	BERK.
Heptacodium miconioides (seven son flower)	Full	*	Full	Full	Begin/Full	Full	Full	Begin/Full
Clematis terniflora (sweet autumn clematis)	Full	Full	Full/End	Full	Full	Full	Full/End	Full
Fallopia japonica (syn. Polygonum cuspidatum) (Japanese knotweed)	Full	Full/End	Full/End	Full	Full/ End	Full/End	Full/End	Full/End
* = no activity to report/information not available

 

Regional Notes

Cape Cod Region (Barnstable)

General Conditions:

The average temperature for the period from September 4 through September 18 was 64ºF with a high of 79ºF on September 4 and a low of 47ºF on September 5. Overall, temperatures have been very consistent with highs in the 70s and lows in the 50s and sunny days. During the period no precipitation was observed. Over the last 6 weeks less than an inch of precipitation has been recorded. Soil moisture is dry.

The lack of precipitation has hampered lawn renovation, planting, and transplanting projects that are usually ideal for late summer/early fall. Unirrigated landscapes are showing early fall color, wilting, scorch, and defoliation from lack of soil moisture. Fortunately, some relief in the form of precipitation appears to be on the way.

Herbaceous plants seen in bloom during the period include turtlehead (Chelone spp.), bluebeard (Caryopteris incana), Japanese anemone (Eriocapitella hupehensis), goldenrods (Solidago spp.), and asters (Symphotrichum spp.). Woody plants observed in bloom include Franklinia (Franklinia alatamaha), crepe myrtle (Lagerstroemia indica), butterfly bush (Buddleja davidii), and rose-of-Sharon (Hibiscus syriacus).

Pests/Problems:

Insects or insect damage observed during the period include box tree moth caterpillars on boxwood, fall webworm damage on tupelo (caterpillars no longer present), tupelo leafminer on tupelo (while damage does not impact plant health, fall foliage of heavily impacted trees will suffer), turpentine beetle damage on pitch pine, hemlock woolly adelgid on hemlock, hemlock elongate scale on hemlock, locust leafminer on black locust, sooty mold from white pine aphid on white pine, oleander aphid on milkweed, and chilli thrips on bigleaf hydrangea.

Disease symptoms or signs observed during the period include powdery mildew on numerous hosts, beech leaf disease on beech, cercospora leaf spot on bigleaf hydrangea, hydrangea rust on smooth hydrangea, pear trellis rust on Bradford pear, septoria leaf spot on Rudbeckia, foliar nematode on hosta and astrantia, guignardia leaf spot on horsechestnut, leaf spot on red twigged dogwood, white smut on gallardia, and leaf spot on chrysanthemum.

Weeds seen in bloom during the period include English ivy (Hedera helix), mugwort (Artemisia vulgaris), carpetweed (Mollugo verticillata), spotted spurge (Euphorbia maculata), redroot pigweed (Amaranthus retroflexus), and yellow wood sorrel (Oxalis stricta).

Other problems observed during the period include deer browse of hosta, snails, and slug damage on various herbaceous plants. Yellowjackets are more noticeable seeking out sugary foods.

Southeast Region (Dighton)

General Conditions:

Since the last report, the highest temperature recorded was 84ºF on Saturday, September 14^th, while the lowest was 52ºF on the mornings of Wednesday, September 4^th, Monday, September 9^th, Wednesday, September 11^th, and Thursday, September 12^th. The average temperature over the past two weeks was 65ºF, with a humidity of 76%. There has been no precipitation. Plants are visibly wilted, dropping leaves, and showing fall colors. The highest wind speed was 13 mph from the south-southeast in the afternoon of Friday, September 13th. The soil temperature in full sun was 71ºF and in shade 66ºF at 3:00 PM on September 18th.

Among the plants in flower are Fallopia japonica (Japanese knotweed) and Clematis terniflora (sweet autumn clematis).

Pests/Problems:

We haven’t had any significant rainfall in more than a month. Soils are dry, and plants are wilting. Despite the lack of rainfall, county mosquito projects continue to warn of the threat of eastern equine encephalitis (EEE) and West Nile virus (WNV) from infected mosquitoes.

North Shore (Beverly)

General Conditions:

Dry conditions continue to persist with no rainfall recorded at Long Hill during this reporting period. Weather conditions were very suitable for outdoor activities with day temperatures mostly in the 70s. Temperatures above 80ºF were recorded only on three days during this period. The average daily temperature was 64ºF with a minimum temperature of 47ºF recorded on September 11 and a maximum temperature of 84ºF recorded on September 13. Nighttime temperatures were mostly in the low to mid 50s, providing very comfortable sleeping weather. The weather forecast for the next 10 days shows that rain is expected on some days.

Woody plants seen in bloom include, Franklin tree (Franklinia alatamaha), seven-son flower (Heptacodium miconioides), blue mist shrub (Caryopteris x clandonensis), and bush clover (Lespedeza thunbergii). Herbaceous plants seen in bloom include New England aster (Symphyotrichum novae-angliae), garden phlox (Phlox paniculata), Rudbeckia (Rudbeckia hirta), Japanese anemone (Anemone x hybrida), hardy geranium/cranesbill (Geranium spp.), pink turtlehead (Chelone obliqua), begonia (Begonia grandis), and autumn crocus (Colchicum autumnale). An assortment of annual plants including garden mums are also contributing color in landscapes.

Pests/Problems:

Due to drought during the summer months, some plants are showing signs of drought stress such as yellowing and browning, premature leaf drop, and early foliage color change. Powdery mildew (Microsphaera alni) is still being observed on some lilac varieties and on New England aster. Crabgrass and other weeds such as ragweed (Ambrosia artemisiifolia), and Japanese knotweed (Fallopia japonica, formerly Polygonum cuspidatum) (Japanese knotweed) are thriving in the landscape. Deer browsing was observed on some vegetable plants. Mosquitoes are still active at dawn and dusk. Ticks are also active.

East (Boston)

General Conditions:

We have been experiencing summer-like conditions. The past two weeks have been sunny, warm and very dry. Daytime temperatures averaged 79ºF, with a high of 87ºF on September 17^th. Overnight lows were consistent, averaging 55ºF. Boston (Logan) is reporting 28 consecutive days with no measurable precipitation. We did record 0.02 inches in Boston (Weld Hill) on September 7^th. This is insignificant in the big picture.

The growing season is winding down, but we continue to accumulate growing degree days; we are currently at 2733 GDD’s. Heptacodium miconoides (seven-son flower) is in full bloom. Irrigated perennial beds continue to attract pollinators. Monarch butterfly caterpillars (Danaus plexippus) have been observed feeding on Asclepias spp. (milkweed).

Pests/Problems:

We have been experiencing unfavorable growing conditions for landscape plants. It has been extremely dry and warm. We have not received any significant precipitation in September. Total rainfall for August was 2.35 inches, which fell between the 2^nd and the 20^th. Plants are showing signs of stress, turf is going dormant. Early leafdrop is occuring on Amelanchier spp. (serviceberry), Betula spp. (birch), Cornus spp. (dogwood), and Populus spp. (poplar).

Metro West (Acton)

General Conditions:

Despite the first day of autumn arriving just around the corner on September 22^nd, summer weather is still hanging on with daytime temperatures recorded into the mid 80’s. Few signs of autumn are evident with some fall foliage colors, shortened days, and cooler evening temperatures. September’s average rainfall is 3.77” and a meager 0.026” of precipitation has been recorded for the month so far and plants are looking stressed.

Colchicum autumnale (autumn crocus), Heptacodium miconioides (seven-son flower), and Hibiscus moscheutos (swamp mallow) have been observed in some stage of bloom.

Pests/Problems:

Plants are stressed due to the lack of rain that has been exasperated by warm if not hot temperatures. Signs of plant stress include premature leaf drop, foliage discoloration, and flagging. Impacts of the more recent dry conditions are many and some include outdoor water restrictions, brittle trees, trees susceptible to pests, and wildfire risks.

According to the Massachusetts Drought Status, updated as of August 13th, a Level 0 – Normal status was declared for the Metro West area. With the lack of any significant rain, I anxiously await to see an updated drought report. The task force met recently, and an updated report is due out any day now and will certainly reveal worsening conditions. (Editor's note: the MA Drought Status has not been updated as of the time of publication. The U.S. Drought Monitor, linked above, does not show the Acton area as under an official drought designation as of Thursday 9/19)

Look to the official websites of the MA Executive Office of Health and Human Services for additional information on Eastern Equine Encephalitis (EEE) and the MA Department of Public Health (MDPH) for current reports of EEE and West Nile virus occurances in the state. Also see the report below under Insects and Other Arthropods (Medically Important Pests) for more details. Currently, towns surrounding Acton are at high-risk for EEE and residents are encouraged to take precautions.

Central Region (Boylston)

General Conditions:

The autumnal equinox approaches and warm dry weather persists into the last spell of summer. With temperatures averaging 78.8ºF (highest being 85.6ºF on the 13th), nights have dropped as low as 51.6ºF on the 8th. Precipitation was recorded at 0.10 inches since the last report, creating dry conditions.

Some plants that can be seen blooming currently are late flowering asters such as: white wood aster (Eurybia divaricate), New York aster (Symphyotrichum novi-belgii), purple-stemmed aster (Symphyotrichum puniceum), turtlehead (Chelone spp.), and closed gentian (Gentiana clausa). Goldenrod (Solidago spp.) continues to bloom throughout the landscape.

Pests/Problems:

As was mentioned in general conditions, it has been extremely dry, creating dry soil conditions, early foliage color change, and even foliage which has completely dried up and dropped. A lot of established plants are exhibiting stresses such as drooping leaves and defoliation from the drought-like conditions. Some problematic plants seem to be thriving by flowering/fruiting/going to seed such as Japanese knotweed (Polygonum cuspidatum).

Some pests/problems seen more recently are birch sawfly (Arge pectoralis) and continuations of aphids on milkweeds (Asclepias spp.) Though the weather has exhibited drought-like conditions, mosquitoes continue to be quite active during early and late hours of the day; surrounding counties having precautions in place due to risks of EEE continuing into the late season.

Pioneer Valley (Amherst)

General Conditions:

The autumnal equinox is almost upon us, and we’ve been locked into an extended pattern of warm and sunny days with cool nights, making for some superb early fall conditions. One major downside, however, is the lack of precipitation. Since the last soaking rainfall on 8/18–19, there’s been only one rain event on 9/7, and accumulations were nothing to write home about (0.2–0.6”). Upper surface soils are really drying out, especially in full sun settings. It’s been a long time since we’ve had to properly irrigate here in the tri-counties. Going back to the record-setting rainfall of July 2023, there’s been plentiful and regular rain until this recent dry stretch. Established trees and shrubs should be able withstand this late summer dry spell. From June 1 to August 20, most weather stations in the valley recorded between 14–16” of rain, so there’s still plentiful moisture at lower soil horizons. Newly transplanted trees and shrubs will need a soaking irrigation of the root zone. Hand check the soil following irrigation to ensure the soil is actually wet, as bark mulch can absorb a significant volume of water before it soaks through.

Frogs, spiders, and crickets are still abundant across the landscape as we continue to lose several minutes of light each day. Acorns are dropping and squirrels are busy digging and stashing their hordes. Winterberry and dogwood fruits are quickly reddening. Early fall foliage is developing on scattered trees and the bright sun and cool nights should produce a spectacular display very soon now. The dry weather has helped to suppress mosquito populations.

Pests/Problems:

The beech leaf disease (BLD) nematode (Litylenchus crenatae ssp. mccannii) has been actively migrating to the buds that will produce next year’s growth. While the nematode requires a film of water to move on plant surfaces, they can withstand periods of desiccation until they’re rehydrated. Despite the lack of rain, heavy dew formation during the morning hours likely provides all the moisture they need. The severity of BLD this year across the tri-counties is truly staggering. There were certainly areas of heavy disease present already, but this year saw a rapid expansion of high severity symptoms throughout western Mass. Many of the forests in the western hill towns are dominated by American beech, primarily in the understory where beech thrives as the most shade-tolerant hardwood. The mortality that will ensue over the next several years will transform these forests to a degree not seen since the chestnut blight epidemic. Red maple, sugar maple and red oak will hopefully regenerate in large numbers.

Lilac leaf blotch, caused by the fungal pathogen Pseudocercospora, is once again causing premature defoliation on lilac (Syringa vulgaris). Brown spots, blotches and a complete blight have developed over the past four to six weeks, leaving some plants badly defoliated.

Berkshire Region (West Stockbridge)

General Conditions:

Despite a recent warming trend where daytime temperatures have been consistently in the lower 80ºF range, there has been a cool trend at night. The highest temperature for the latest 2-week scouting period occurred on September 14 with 80ºF in Pittsfield, 82ºF in Richmond, and 83ºF in North Adams. The nighttime temperatures have been consistently in or near the 40s at these 3 sites. The lowest temperatures for the 2-week period were: 41ºF in Richmond, 43ºF in Pittsfield, and 44ºF in North Adams. All the lows occurred on 9/11. The average temperatures for these sites were: 61.4ºF for Pittsfield, 62.0ºF for Richmond, and 62.1ºF for North Adams. These averages are about 3ºF lower than that of the previous 2-week scouting period.

The biggest concern, weather-wise, of late has been the lack of rain. Total rainfall for the past 4 weeks (August 21-September 18) has been less than an inch throughout the County: North Adams received 0.61 inches, Richmond had 0.71 inches, and Pittsfield got 0.74 inches. Of course, soils are now quite dry. This a concern since September is a key month for planting trees, shrubs, and many herbaceous perennials and the seeding of new lawns. Typically, September is cooling down and moist. Watering and mulching are musts at this time.

Despite the dry conditions, there are some bright spots in the landscape. A standout at this time is autumn crocus (Colchicum autumnale), often called “naked ladies” since they are devoid of leaves when in bloom. It is not only late blooming flowers that put on a show now. There are many shrubs with colorful fruit, perhaps none showier than that of beautyberry (Calicarpa dichotoma).

The lack of rain has also affected growth of existing turfgrass. Non-irrigated lawns have shown little growth. Closely mowed lawns are showing many browned spots. If irrigation is not feasible, grass should be cut no lower than 3 inches.

Pests/Problems:

The most obvious issue now is the premature fall color and dropping of leaves of trees and shrubs. This is largely due to a combination of various fungal diseases which infected leaves earlier in the year when rains were frequent. Clean up of infected leaves wherever possible is important to reduce foliar diseases next year. Insect problems are minimal at this time.

Asian jumping worms remain numerous and can easily be found when weeding gardens since the worms are so close to the soil surface.

Voles, mice, chipmunks, and deer continue to be voracious feeders of plant foliage.

 

Regional Scouting Credits

• CAPE COD REGION - Russell Norton, Horticulture and Agriculture Educator with Cape Cod Cooperative Extension, reporting from Barnstable.
• SOUTHEAST REGION - Brian McMahon, Arborist, reporting from the Dighton area.
• NORTH SHORE REGION - Geoffrey Njue, Green Industry Specialist, UMass Extension, reporting from the Long Hill Reservation, Beverly.
• EAST REGION - Kit Ganshaw & Sue Pfeiffer, Horticulturists reporting from the Boston area.
• METRO WEST REGION – Julie Coop, Forester, Massachusetts Department of Conservation & Recreation, reporting from Acton.
• CENTRAL REGION - Mark Richardson, Director of Horticulture, and Anna Petrie, reporting from New England Botanic Garden at Tower Hill, Boylston.
• PIONEER VALLEY REGION - Nick Brazee, Plant Pathologist, UMass Extension Plant Diagnostic Lab, reporting from Amherst.
• BERKSHIRE REGION - Ron Kujawski, Horticultural Consultant, reporting from Great Barrington.

Woody Ornamentals

Diseases

Recent pests, pathogens, or problems of interest seen in the UMass Extension Plant Diagnostic Lab, a select few:

Lilac leaf blotch, caused by Pseudocercospora, on numerous mature lilac (Syringa vulgaris) throughout the region. Samples have been submitted from plants ranging in age from 5 to 30 years old, residing in part shade to full sun, with and without supplemental irrigation. Beginning in late July to early August, brown-colored spots and blotches developed on the foliage. They quickly expanded to consume significant portions of the leaf, in some cases causing a total blight. Infected leaves are often prematurely shed from the canopy and some plants are now badly defoliated. An outbreak of lilac leaf blotch occurred in 2023 and for many landscapers, it was the first time the disease was observed in high severity. Abundant overwintering inoculum combined with the wet spring likely facilitated another outbreak in 2024. Last year, many defoliated plants pushed new growth with scattered blooms. This late season growth did not have time to fully harden off and subsequently died over the winter due to freeze injury. In addition to leaf blotch, some plants are also experiencing shoot tip dieback caused by opportunistic cankering fungi like Phomopsis. Most plants are also impacted by lilac powdery mildew (Erysiphe syringae), although this disease alone typically causes only minor, aesthetic injury. Fungicide application in 2025 may be warranted for certain plants, with applications beginning in June and on extended intervals (e.g. 21 days) into late summer.

Needle blight caused by Didymascella thujina (previously Keithia thujina) on Green Giant arborvitae (Thuja plicata × standishii). Didymascella is a common and sometimes destructive pathogen of western redcedar (T. plicata)throughout its native range, but the fungus is considered uncommon in eastern North America. This is the first time the disease has been observed at the UMass Plant Diagnostic Laboratory, although reports from other regional labs have occurred. Symptoms develop on one-year-old needles and appear as large, black-colored lesions that swell to release clear spore masses. Once the spores are discharged, the old fruiting bodies appear as sunken pits and were first confused with insect chewing injury. Causing further confusion was a secondary tip dieback caused by the common needle blight pathogen Pestalotiopsis. Needle scales infected by Didymascella may not be killed outright and needle elongation continues the following year (visible in the photo). The infected trees are 10 years old and were planted into a shaded landscape with good loams soils and supplemental irrigation from lawn sprinklers. The rising popularity of Green Giants may result in higher levels of disease incidence in the future. Shade and free moisture on the needles can help to promote the disease.

Fire blight, caused by the bacterium Erwinia amylovora, on apple (Malus domestica) and pear (Pyrus communis). In addition, apple scab (Venturia inaequalis) and cedar-quince rust (Gymnosporangium clavipes) were present on the apple, while Fabraea leaf and fruit spot (Diplocarpon mespili) was found on the pear. The trees are approximately 10 years old and were transplanted at a residential property three years ago. They reside in full sun at an open, windy site, receive drip irrigation, and have experienced lawn mower and string trimmer injury. In 2022, the trees suffered from a serious fire blight outbreak and were put on a minimal pesticide IPM program to control the variety of diseases present. Apple scab lesions and the conspicuous, hair-like spore tendrils of cedar-quince rust were present on the apple fruits. Fabraea leaf and fruit spot (also known as Entomosporium leaf spot) is a common foliar and fruit disease pathogen on pear, quince (Cydonia) and hawthorn (Crataegus) in the region. Untreated pears are often badly defoliated by late August due to this disease. The fruit spots had cream-colored, waxy spore masses present, and when viewed microscopically appear like small insects (see photo). The pathogen, Diplocarpon mespili (syn. Entomosporium mespili), is responsible for a serious foliar blight and premature leaf shedding on several large and shaded hawthorns on the UMass campus every year.

Report by Nick Brazee, Plant Pathologist, UMass Extension Plant Diagnostic Lab, UMass Amherst

Insects and Other Arthropods

 

MDAR is Looking for Help from Citizen Scientists! Help spot invasive species early and learn about what’s living on or near the plants they threaten! This October 1 to 15, 2024, pick a spot in Massachusetts where trees are growing, and record all the living things you see on or near those trees. This year’s event will focus on spotted lanternfly and Asian longhorned beetle. For information about how to participate, visit the: Spot Invasive Insects: A Massachusetts BioBlitz page.

 

Invasive Updates:

• Asian Longhorned Beetle is still present in Worcester, Shrewsbury, Boylston, West Boylston, and parts of Holden and Auburn, MA. If you suspect you’ve found this insect or the damage it causes, please report it to the Asian Longhorned Beetle Eradication Program office in Worcester, MA at 508-852-8090 or toll free at 1-866-702-9938.

To report an Asian longhorned beetle find online or to compare it to common insect look-alikes, visit the Asian Longhorned Beetle Report page from the MA Department of Agricultural Resources.

• Box Tree Moth has been detected in the following Massachusetts communities: Plymouth, Bourne, Sandwich, Barnstable, and Yarmouth. A map of these locations is available at MDAR’s Invasive Pest Dashboard. If you believe you have found this insect, please take a photo, note your location, and report it immediately to the MA Department of Agricultural Resources using their Report a Pest Form.

The USDA APHIS has announced a new quarantine for box tree moth in Massachusetts and Ohio, and has expanded existing quarantines in Michigan and New York. This includes conditions for interstate movement of regulated Buxus species. This quarantine includes the entire Commonwealth of Massachusetts. The federal order states:

“Boxwood plants may only be moved interstate from a quarantined area from an establishment operating under a compliance agreement, and only if accompanied by a certificate issued by a State Agricultural Authority certifying that the requirements of this Federal Order and the compliance agreement have been met. These requirements will prevent producers and distributors of boxwood from moving infested plants interstate. State Agricultural Authorities may prescribe additional safeguards and protocols.

All other regulated articles of boxwood, including plant parts, pieces, cuttings, clippings, debris, and any portion of the plant, alive or dead, except for decorative purposes, are prohibited from movement.”

MDAR has recently sent a notice to boxwood growers in Massachusetts of the following:

"Effective May 22, 2024, the USDA has issued a Federal Order establishing a quarantine for the entire state of Massachusetts. In an effort to restrict the movement of box tree moth, boxwoods (Buxus spp.) may no longer be exported from Massachusetts except by an establishment operating under a compliance agreement (CA) to be issued by MDAR. Anyone wishing to register for a CA must go to the Massachusetts Department of Agricultural Resources box tree moth page and click on the EXPORTS link, and fill out the form. An MDAR staff person will follow up within one week. Please note that the quarantine does NOT restrict in-state sales, movement within the state, or import of boxwoods into Massachusetts. If you have any further questions, please feel free to contact either MDAR (taryn.lascola@mass.gov) or USDA (203-741-5641)."

To read the full announcement of the box tree moth quarantine for Massachusetts from MDAR, please visit the Massachusetts Introduced Pests Outreach Blog.

Need information about monitoring and trapping box tree moth? Check out this newly available Box Tree Moth Monitoring & Trapping fact sheet from UMass Extension. 

• Elm Zigzag Sawfly has been detected in the following Massachusetts communities: Tyringham, Washington, Williamsburg, Amherst, Great Barrington, New Ashford, Dalton, Chesterfield, Holyoke, Hinsdale, Granby, Greenfield, Westfield, Chester, Deerfield, Becket, Sunderland, Williamstown, Windsor, Erving, Palmer, Ware, and Hardwick. A map of these locations can be found on the MA DCR Forest Health Program Elm Zigzag Sawfly page.  If you believe you have found this insect, please take a photo, note your location, and report it immediately using MA DCR’s Massachusetts Elm Zigzag Sawfly Reporting Form.

Please report any suspicious defoliation of elm to the previous reporting link.

• Emerald Ash Borer is well established across most of Massachusetts. A map of these locations from the MA Department of Conservation and Recreation is available.
• Jumping Worms are non-native earthworms that impact natural ecosystems. Available resources include a fact sheet about earthworms in Massachusetts and jumping worm FAQ’s. In the fall, adult jumping worm sightings typically increase due to the life cycle of these earthworms and their large and noticeable size at this time of year.
• Spotted Lanternfly now has established populations in the following locations in Massachusetts: Holyoke, Springfield, West Springfield, Agawam, Fitchburg, Worcester, Shrewsbury, Southborough, Ashland, Wellesley, Weston, Chelmsford, Grafton, Lawrence, Lynn, Wilbraham, Ludlow, Chicopee, Seekonk, Attleboro, Andover, Framingham, Norton, Upton, and Longmeadow, MA. A single, dead adult spotted lanternfly was recently seen in the Southwest Residential Area of the UMass, Amherst campus. MDAR was notified and they do NOT believe there is an established population at UMass. This was likely a single, dead adult accidentally transported. (Photo courtesy of Jim Williams.) It remains important to photograph and report this insect in Massachusetts! 

In areas of the state where spotted lanternfly is present and has been observed through monitoring, the SLF Management Guide suggests management options for SLF nymphs and adults. Spotted lanternfly should not be managed using insecticides in locations where the insect has not been confirmed in the state. This may result in unnecessary, costly, and environmentally irresponsible applications. The first step in areas outside of the communities listed above for MA is to report SLF to MDAR (also see link below).

For homeowners now living with spotted lanternfly in Massachusetts, the MA Department of Agricultural Resources offers the following decision-making guides:
• Checklist for residents living in infested areas
• Checklist for businesses in infested areas
• Management guide for homeowners

If you believe you have found this insect, please take a photo, note your location, and report it immediately using the Spotted Lanternfly Report Form. Available resources include a map of spotted lanternfly locations in Massachusetts from the MA Department of Agricultural Resources, MDAR’s spotted lanternfly fact sheet, UMass Extension’s Spotted Lanternfly Management Guide, and an SLF InsectXaminer episode.

New SLF PSA's are available from the MA Department of Agricultural Resources! Share with your friends!

Medically Important Pests:

• Ticks are a serious public health concern and may be active in managed landscapes any time temperatures are above freezing. 

Check your children and loved ones and selves for ticks daily! High exposure risk, such as recreational and work time outdoors, summer camps, and back-to-school time outside combined with tick activity is a recipe for tick bites. Check your entire body and remove any attached ticks immediately. If an attached tick is found, submit the tick to one of the testing resources in the link below and go see your physician immediately. Lyme disease is only one of the pathogens ticks can vector. Others include but are not limited to babesiosis, anaplasmosis, ehrlichiosis, and many more!

Blood tests for tick borne pathogens are available. Ask your doctor about FA and Western blot testing. A doctor may prescribe doxycycline or amoxicillin or other antibiotics to treat certain tick-borne pathogens. Remember, the pathogen that causes babesiosis is different and requires different treatment! Co-infections are possible – meaning more than one pathogen may be present at a time. Test for all of them. UMass Extension cannot provide medical advice. This information is for educational purposes only.

Encounters with deer ticks can increase in New England in April, October, and November; however, precautions should be taken year-round to prevent tick bite exposure. Available resources include tick information from Cape Cod Cooperative Extension, personal protective measures, and a list of potential tick testing resources. The New England Center of Excellence in Vector-Borne Diseases (NEWVEC) also provides the latest tick information and resources.

• Mosquitoes and the diseases they vector are also a serious public health concern and remain active at this time! Available resources include Mosquito Repellents from the Department of Public Health and Prevent Mosquito Bites from the Centers for Disease Control and Prevention. The Massachusetts Department of Public Health tests for Eastern Equine Encephalitis (EEE) and West Nile Virus (WNV) from June to October. The Massachusetts risk maps are currently available for both EEE and WNV. 

As of September 13th, EEE has been detected in mosquito samples taken from Plymouth, Barnstable, Essex, Norfolk, Bristol, Middlesex, and Worcester counties in Massachusetts. The MA Department of Public Health now ranks certain communities at moderate risk (meaning there is EEE in mosquito populations in that area now) in these counties. Middleborough, Carver, and Plymouth, MA are ranked as high risk (meaning “conditions likely to lead to infection of a person with EEE are occurring in your area”). Oxford, Sutton, Douglas, and Webster, MA have been elevated to critical risk, meaning “excessive risk from EEE virus exists, and a person with EEE infection has been identified in your area”. And most recently, Harvard, Groton, Boxborough, Littleton, Acton, Concord, and Carlisle have also been elevated to high risk. People living and working in these communities should take the precautions as suggested in the links above to protect themselves from mosquito bites.

As of September 13th, WNV risk has been increased to moderate (infection with WNV is likely or has already occurred) in many communities in the following Massachusetts counties: Norfolk, Plymouth, Bristol, Dukes, Middlesex, Worcester, Hampden, Essex, Suffolk, Berkshire, Barnstable, and Franklin. The list of communities that have been elevated to high risk, meaning “more people may get infected with WNV in your area”, has become too long to feature here. If you are in any of the above counties, search for your city or town on the Massachusetts risk map. Individuals in these areas should continue to take precautions to protect themselves from mosquito bites.

As of 9/13/2024, there have been 4 human cases and 2 animal cases of EEE in MA and 11 human cases of WNV in MA. As of 9/13/2024 there have been 95 EEE positive and 317 WNV positive mosquito samples in MA. As of 9/13/2024, the MA Department of Public Health announced the 11th human case of West Nile virus and EEE risk level change in Massachusetts. See that article for additional ways to protect yourself and loved ones. Continue to protect yourself from mosquitoes until the first hard frost in MA.

• Wasps/Hornets: Many wasps are predators of other arthropods, including pest insects such as certain caterpillars that feed on trees and shrubs. Adult wasps hunt prey and bring it back to their nest where young are being reared as food for the immature wasps. At this time of year, this behavior can cause conflict between wasps or hornets and humans. It is best to sit still, and wait for the insect to move on (rather than make it feel threatened, resulting in it using its sting as self-defense). For example, this photo shows a wasp in the family Vespidae helping itself to some turkey from an Extension professional’s sandwich on August 23, 2024 in Sequia National Park, CA. Once a piece of the turkey was acquired by the insect, it moved on and gave enough time to move away from the area.

A common such example are the paper wasps (Polistes spp.) who rear their young on chewed up insects. Paper wasps can sting, and will defend their nests, which are open-celled paper nests that are not covered with a papery “envelope”. These open-celled nests may be seen hanging from eaves or other outdoor building structures. Aerial yellow jackets and hornets create large aerial nests that are covered with a papery shell or “envelope”. Common yellow jacket species include those in the genus Vespula. Dolichovespula maculata is commonly known as the baldfaced hornet, although it is not a true hornet. The European hornet (Vespa crabro) is three times the size of a yellow jacket and may be confused for the northern giant hornet (Vespa mandarinia). The European hornet is known to Massachusetts, but the northern giant hornet is not. If you are concerned that you have found or photographed a northern giant hornet, please report it using the MA Department of Agricultural Resources Report Pest Sightings page. Some people are allergic to stinging insects, so care should be taken around wasp/hornet nests. Unlike the European honeybee (Apis mellifera), wasps and hornets do not have barbed stingers and therefore can sting repeatedly when defending their nests. It is best to avoid them and, if that cannot be done and assistance is needed to remove them, consult a professional.

Tree & Shrub Insect & Mite Pest Suggested Scouting:

• Ailanthus Webworm, Atteva aurea (formerly A. punctella), is a tropical ermine moth from the family Attevidae. While they may be referred to as tropical, apparently the moths themselves can tolerate much colder temperatures than their original host plants. Prior to 1784 when tree of heaven (Ailanthus altissima) was introduced into Philadelphia, PA, the ailanthus webworm was restricted to southern Florida and points south. It would appear that this restriction in distribution was due to the distribution of their original host plants in the genus Simarouba. Once tree of heaven’s range extended from the north to the south, including Florida, the moths were able to move northward on the newly available and suitable host plant. Larvae of this moth feed almost exclusively on tree of heaven in the northern parts of its expanded range. Occasionally, these caterpillars will defoliate tree of heaven, but not to the extent that they could provide any form of control of this invasive tree. (On younger plants, sometimes caterpillars can completely defoliate the trees and strip the bark off of small branches.) Larvae cluster together in a loose web. Larvae of the ailanthus webworm have five white longitudinal lines on an olive-brown colored base with sparsely hairy bodies. Caterpillars are found in the late summer. Larvae pupate within their webs, moths emerge, mate, and then lay their eggs on the outside of the webs. Multiple, overlapping generations can occur per year.
• Andromeda Lace Bug is most commonly encountered on Japanese andromeda, however other host plants may be impacted. Most activity from this insect occurs between late May through September, with several generations occurring per year. Both nymphs and adults feed on host plant leaf undersides and cause white/yellow-colored spots or chlorosis to occur on host plant leaf surfaces. 
• Azalea Lace Bug is a pest of both deciduous and evergreen azaleas (Rhododendron spp.), however resistance has been reported in Rhododendron atlanticum, R. arborescens, R. canescens, R. periclymenoides, and R. prunifolium. The insects feed on host plant leaf undersides, and cause chlorosis on leaf surfaces. Azalea lace bugs are active throughout the summer.
• Fall Home-Invading Insects: Various insects, such as ladybugs, boxelder bugs, seedbugs, and stink bugs will begin to seek overwintering shelters in warm places, such as homes, throughout the next couple of months. While such invaders do not cause any measurable structural damage, they can become a nuisance, especially when they are present in large numbers. While the invasion has not yet begun, if you are not willing to share your home with such insects, now should be the time to repair torn window screens, repair gaps around windows and doors, and seal up any other gaps through which they might enter the home.
• Hickory Tussock Moth caterpillars are out and about, as is common this time of year. Lophocampa caryae is native to North America with caterpillars of this species found from July through September. These white, black and hairy caterpillars may be seen wandering landscapes. Hickory, walnut, hornbeam, and others are favored host plants, although these caterpillars may be seen on many other trees and shrubs. The hairy caterpillars themselves or their cocoons may cause dermatitis in sensitive individuals, especially children. Avoid handling and teach children to ask an adult first before picking up a hairy caterpillar. Typically does not require management.
• Lily Leaf Beetle strikes again! Adults are still active in Chesterfield, MA as of 9/16/2024. This plant was purchased this season. It is suspected that the insect came in on the plant, but that cannot be determined for sure. It may have also been present on a neighboring property and made its way to this location.

• Locust Borer adult beetles are typically active by early September until the first frost, often associated with goldenrod. Beetles are attractive – black with a series of yellow stripes throughout the body and approximately ½-1 inches long. Black locust (Robinia pseudoacacia) is the host of the wood boring larvae of this visually striking insect.

• Magnolia Scale reports to UMass Extension have increased as now is the time when adult female scales are large, covered in a white, waxy coating, and very noticeable. Nymphs will soon wander to the newest twigs of their host plants where they will settle to overwinter. When safe and practical to do so, such as on smaller trees, large female scales can be removed with a soft brush (without damaging the host plant bark). See link for more management options.

• Obscure Scale may be present on oak, chestnut, hickory, or pecan. Newly hatched crawlers may be active on infested stems and branches for a long period of time, roughly between mid-July through September. Because the scale coverings, even of dead scales, cling to the host plant bark, heavy infestations that have been present for multiple years may be detected any time of the year if the layered, encrusted scales are searched for. Take note if branches appear deformed or lumpy/misshapen.

• Pear Sawfly is an introduced (European) species that feeds on a wide variety of trees and shrubs, including pear, cherry, cotoneaster, crabapple, hawthorn, mountain ash, plum, and shadbush. Sawfly larvae feed on the leaves of their hosts, skeletonizing them at first and eventually leading to leaf browning and early leaf loss. A second generation of adult sawflies may emerge from pupal cells in the soil by August. Second generation larvae may feed on host plant leaves through September until they drop to the soil to overwinter as pupae. 
• Pine Needle Scale can be a very serious pest of the needles of ornamental pines. Light infestations may go unnoticed and typically do not cause considerable damage. As a population increases, this scale insect feeds with piercing-sucking mouthparts to remove host plant fluids from the needles, causing them to eventually turn yellowish in color and possibly brown. Twigs and entire branches may eventually be killed. Lower branches typically die first. Depending upon geographic location, one or two generations of pine needle scales occur per year. If a second generation is present, second-generation crawlers are present by late July through September. Two generations per year occur in Massachusetts. More northerly locations may have a single generation per year.
• Redheaded Pine Sawfly larvae feed on the outside of host plant needles. This results in shriveled, browned, and straw-like needles that remain attached to the hosts. Older caterpillars are capable of eating the entire needle. Feeding began in the spring and early summer, and can sometimes be extensive by the fall. Redheaded pine sawfly larvae were observed on 8/3/2024 in the Montague Sandplains (Montague and Franklin County, MA) by Dr. Paul Sievert, emeritus faculty of UMass Amherst. Parasitoid wasps possibly in the genus Exenterus were observed interacting with the larvae (see photos). 
• Southern Pine Beetle has been trapped in Massachusetts since 2015. By 2022 and 2023, southern pine beetle has reached outbreak conditions in small areas of the state, killing pitch pine (Pinus rigida), particularly on Martha’s Vineyard and Nantucket islands in MA. If you believe you have found infested pitch pine in Massachusetts, please report southern pine beetle using the Massachusetts Southern Pine Beetle Reporting Form from MA DCR.
• Spotted Tussock Moth (Lophocampa maculata) is a native species known to both the east and west coasts of the United States. Mature caterpillars of this species are known from July through September. Host plants include basswood, cherry, elm, hazel, maple, oak, poplar, and many others (Wagner, 2005). This species is not typically a significant pest of its host plants and management may not be necessary. It is more of a curiosity, due to its bright and beautiful coloration. As with most tussock moths, discourage the handling of these hairy caterpillars by children. Some sensitive individuals may react (dermatitis) to the hairs.
• Viburnum Leaf Beetle larvae may be found anywhere on the leaves and usually in groups. When young, larvae feed on the undersides of the leaves. As they grow larger, they may feed on the upper surface. Larval development may take approximately 8-10 weeks to complete and 3 larval instars are reported. Pupae are yellowish and are found in the soil beneath the host plant. Adults emerge around the middle of July and are brown, smaller than the largest larvae (approximately ¼ inch), and will also feed on the leaves. Adults are present in the landscape until the first hard frost.
• White Marked Tussock Moth is one of many native tussock moth species commonly encountered in the late summer and early fall. Avoid touching these caterpillars or their cocoons: they may cause allergic reactions, especially if their hairs come into contact with sensitive skin (ex. back, stomach, underside of arms) (Wagner, 2005). Contact dermatitis (itching) as a result of interacting with these insects has been reported from schools and daycares. Teach children how to identify and avoid handling cocoons and caterpillars. These caterpillars have urticating (irritating) hairs. Welts may appear on the skin within minutes, but subside the next day; however, itching can last for several days depending upon the sensitivity of the individual.

• Winter Cutworm Eggs: the eggs of Noctua pronuba or the winter cutworm (caterpillar stage) or the large yellow underwing (moth stage) are being seen again on various landscape ornamental and shade trees and shrubs. See photo of the winter cutworm eggs viewed on Japanese elm on 8/22/2024 courtesy of Brady Yacek. This (until now) mysterious appearance of eggs, followed by very minor feeding on leaves (if laid on leaves) and apparent disappearance of the culprit has occurred this time of year for the last few seasons. With the help of Charley Eiseman and Whitney Cranshaw in 2023, the identity of the eggs is finally known. The winter cutworm is a non-native insect that may feed on a variety of plants in the landscape. Larvae mature by the winter and can be seen on mild days in the snow! Pupation is believed to occur in the spring, with adults found in the spring and again in the late summer. There may be two generations per year, but the life cycle of this insect is not completely understood. Increasingly, winter cutworm caterpillars are reported in Massachusetts throughout the winter season (see the Insects section under Turf in the April 7, 2023 Issue of the Landscape Message). The good news is, even though the eggs of this species have been observed on beautyberry, beech, and Japanese white pine in ornamental landscapes in recent years, no significant feeding damage has been seen on these plants. In most cases, although noticeable, the egg masses can be ignored or tolerated.

Beneficials/Non-Pests:

• Monarch Butterflies are one of the most iconic Lepidoptera of North America. Beloved by all ages, these insects impress the public and entomologists alike. Whether it be for rearing their striped caterpillars or the impressive migration completed by multiple generations, monarchs have captured the hearts of many. While providing the necessary food plants (milkweed) for these insects is a noble pursuit, don’t forget that milkweeds are food for many other insects as well, including but not limited to: beetles, bugs, tussock moth caterpillars, and aphids. Just because Danaus plexippus holds the crown, does not mean that insect is the only one with the right to eat.

Report by Tawny Simisky, Extension Entomologist, UMass Extension Landscape, Nursery & Urban Forestry Program

Landscape Weeds

For information about identification of weeds noted below, check out UMass Extension's Weed Herbarium.

Dry conditions and herbicide performance: Just returned from a trip to the MA North Shore and was surprised to see the amount of dryness in eastern Massachusetts. While the North Shore is a bit dry, it was super dry in Bolton, Littleton and Leominster. In these towns, some of the roadside vegetation has severely witted or dropped leaves. Recent US Drought Monitor maps show progressing drought status in eastern MA.

Droughty growing conditions can greatly impact herbicide performance. The best herbicide performance is achieved when both the weed and any desirable plant material is actively growing with no drought and/or heat stress. In weed science, the principle of herbicide selectivity is when an herbicide effectively controls the target weed with no injury or adverse effects to desirable plants. Drought and/or dry growing conditions can change herbicide selectivity. Weeds that are normally susceptible to an herbicide may become tolerant, resulting in poor control. Desirable plants that are normally tolerant of an herbicide may become susceptible, resulting in injury or death. In other words, the best control of a weed and protection of a desirable plant occurs when both types of plants are actively growing. This is important because, due to the current dry growing conditions, there is a possibility that herbicide treatments we have planned may have to be cancelled.

Common reed or phragmites, Phragmites australis: Common reed is now past flowering in New England, so now is the time for herbicide treatment. Glyphosate-based herbicide products are the best choice for the control of common reed. In areas near water, a formulation of glyphosate that is labeled for these areas should be used. Common reed is commonly associated with water and wet habits and will likely invoke the Massachusetts Wetland Protection Act 310 CMR 10.00, so the management of this invasive plant will likely require a permit.

Crabgrass management in turf: We are quickly approaching the point where postemergence herbicide applications are of no value. Focus should shift to reseeding turf areas where the crabgrass has resulted in turf loss. An aggressive verti-cutting or hollow-tine aeration can be used to prepare the area for over-seeding.

Japanese knotweed (Fallopia japonica): As mentioned in the first section, the dry conditions in New England should have us rethinking some of our herbicide applications. Japanese knotweed herbicide applications certainly jump to the “let’s think about it basket”. If the leaves of Japanese knotweed are green with no visible signs of yellowing, then herbicide applications should be completed.

Report by Randy Prostak, Weed Specialist, UMass Extension Landscape, Nursery, and Urban Forestry Program

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Diagnostic Services

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 the Plant Diagnostic Laboratory web site.

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 lab provides test results and recommendations that lead to the wise and economical use of soils and soil amendments. For more information, including current turn-around times, visit the UMass Soil and Plant Nutrient Testing Laboratory web site. The lab is currently accepting orders for Routine Soil Analysis (including optional Organic Matter, Soluble Salts, and Nitrate testing), Particle Size Analysis, Pre-Sidedress Nitrate (PSNT), Total Sorbed Metals, and Soilless Media (no other types of soil analyses available at this time). Check for current turnaround time. Please plan for the fact that date of receipt in the lab is affected by weekends, holidays, shipping time, and time for UMass Campus Mail to deliver samples to the lab.

Tick Testing - The UMass Center for Agriculture, Food, and the Environment provides a list of potential tick identification and testing options at https://ag.umass.edu/resources/tick-testing-resources.

Acknowledgements: UMass Extension gratefully acknowledges the support of the following funding sources for the production of the Landscape Message –

• The Massachusetts Nursery and Landscape Association Fund
• The Massachusetts Department of Conservation and Recreation, Award #ISADCR28219926UMA24A
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