Landscape Message: May 8, 2026

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 plants in the landscape are regular features. The following issue has been updated to provide timely management information and the latest regional news and environmental data. 

This is the fifth Landscape Message of 2026. The next message will be published in one week, on May 15.  

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In This Issue

Regional Scouting Observations

Environmental Data

Plant Phenology

Regional Notes 

     Cape Cod Region (Barnstable)

     Southeast Region (Plymouth)

     North Shore (Beverly)

     East (Boston)

              Metro West (Acton)

              Central Region (Boylston)

              Pioneer Valley (Amherst)

              Berkshire Region (West Stockbridge)

Landscape Pest Reports

Diseases

Insects and Other Arthropods

Weeds

Additional Resources

Regional Scouting Observations

Environmental Data

The following data was collected on or about May 6, 2026. Total accumulated growing degree days (GDD) represent the heating units above a 50ºF baseline temperature collected via regional NEWA stations for the 2026 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.

US Drought Monitor:  At this time, about 98% of the land area of Massachusetts is classified as at least D0 (Abnormally Dry).  Of this, 37% is classified as at least D1 (Moderate Drought). State map as of Thursday, May 7. 

Plant Phenology

The basis of plant phenology is that specific environmental conditions such as temperature, daylength, and precipitation directly influence plant development at a given location. The development of other organisms of interest, such as insects, are also subject to the same factors, and this natural synchrony can aid in decision making that is free of the limitations of calendar dates. The bloom stage of plants can be an especially visible and useful tool for optimizing planting schedules, better timing of cultural activities such as pruning, fertilization, and pest management, or simply taking note of seasonal progress.

Note also that the following is presented as a list of commonly observed indicator species and is not intended as a list of recommended plants, per se.  Plants denoted with # are officially classified as invasive in MA, and plants denoted with + often exhibit invasive or aggressive tendencies.

If you enjoy this publication or depend on it as a resource, consider contributing what you can to support its ongoing success. Click here to donate to UMass Extension!

Regional Notes

Cape Cod Region (Barnstable)

General Conditions:

The average temperature from April 29 to May 6 was 52°F with a high of 65°F on May 4 and a low of 39°F on May 3. The period had a mix of cloudy, partly cloudy and sunny days and was very windy May 4-6.

Precipitation occurred on April 30, and May 2-3 totaling less than 0.75”. Soil moisture is short.

Woody plants observed in bloom include border forsythia (Forysthia x intermedia), skimmia (Skimmia japonica), Korean spice viburnum (Viburnum carlesii), and Japanese flowering cherry (Prunus serrulata ‘Kwanzan’).

Herbaceous plants seen in bloom include barren strawberry (Waldsteinia fragarioides), sweet woodruff (Galium odoratum), barrenwort (Epimedium grandiflorum), and sessile-leaved bellwort (Uvularia sessilifolia).

Pests/Problems:

Cicada damage from last summer is visible on rhododendron resulting in many damaged shoots. Winter injury is still being observed on boxwood (Buxus spp.) and arborvitae (Thuja spp.). Rabbit and vole damage from the winter and spring rabbit damage is also being observed on newly emerging plants.

Needle cast has been observed on pitch pine (Pinus rigida) in the upper Cape region, typically random trees with the entire crown showing symptoms.

Winter moth (Operophtera brumata) larvae, 5-8 mm in size, can be observed in the buds of susceptible hosts. It no longer causes widespread defoliation and does warrant management in ornamentals; however, populations may still be large enough to damage fruit producing apples and blueberries. In recent years minor defoliation from a combination of winter moth and fall cankerworm has been observed in isolated areas of Barnstable, Falmouth, Harwich, Mashpee and Sandwich.

Box tree moth (Cydalima perspectalis) is active and can be found feeding on boxwood (Buxus spp.). Box tree moth overwinters as early instar caterpillar and begins feeding around forsythia bloom (now). Boxwood leafminer (Monarthropalpus flavus) and volutella blight (Volutella buxi) have also been observed during the period on boxwood.

Other insect or disease problems observed during the period include black knot (Apiosporina morbosa) on black cherry (Prunus serotina), fungal leaf spots on rhododendron, fungal leaf spot on mountain laurel (Kalmia latifolia), holly rust (Chrysomyxa ilicina) on holly, cracked cap polypore (Phellinus robiniae) on black locust (Robinia pseudoacacia), tip blight on arborvitae, holly leafminer (Phytomyza ilicicola) on holly (Ilex opaca), red lily leaf beetle (Lilioceris lilii) feeding on Asiatic lily, hemlock woolly adelgid (Adelges tsugae), hemlock elongate scale (Fiorinia externa) on hemlock, cottony camelia scale (Pulvinaria floccifera) on holly, lecanium scale (Parthenolecanium spp.) on oak, and andromeda lacebug (Stephanitis takeyai) symptoms on Japanese andromeda (Pieris japonica).

Weeds seen in bloom include dandelion (Taraxacum officinale), purple deadnettle (Lamium purpureum), speedwells (Veronica spp.), yellow rocket (Barbarea vulgaris), common violet (Viola sororia), and common groundsel (Senecio vulgaris).

Invasive plants in bloom include lesser celandine (Ficaria verna), garlic mustard (Alliaria petiolata), cypress spurge (Euphorbia cyparissias), and Japanese barberry (Berberis thunbergii).

Russell Norton, Horticulture and Agriculture Educator with Cape Cod Cooperative Extension, reporting from Barnstable.

Southeast Region (Plymouth)

General Conditions: 

The weather for the period was characterized by a mix of warm days and cool overcast days. 4 of 7 days reached above 60°F. However, the weather felt a lot cooler due to a high amount of wind towards the end of the period.

We saw very light precipitation on 3 days. Like last week, it was very light and barely amounted to much accumulation. As of April 28, the southern portion of the region is still experiencing some degree of drought.

Forsythia (Forsythia spp.), willow (Salix spp.), and magnolia (Magnolia spp.) are reaching the end of their blooms in most locations. Trailing arbutus (Epigaea repens) was observed blooming, but towards the end of its bloom.

Cherries (Prunus spp.), Vinca (Vinca spp.), daffodils (Narcissus spp.), violets (Viola spp.), rhododendrons (Rhododendron spp.), tulips (Tulipa spp.), bleeding heart (Lamprocapnos spectabilis), wood anemone (Anemone quinquefolia), and phlox (Phlox sp.) are still blooming.

Flowering quince (Chaenomeles spp.), lowbush blueberry (Vaccinium augustifolium), cinquefoils (Potentilla spp.), bearberry (Arctostaphylos uva-ursi), and bride-wreath spiraea (Spirea prunifolia) have begun blooming.

Pests/Problems:

Rainfall has been frequent, but light. The result is that you can find plants with either bacterial and/or fungal diseases, while suffering from drought stress.

Deer, rabbit, and groundhog browsing remain prevalent. Bagworm moths (Thyridopteryx ephemeraeformis) have been observed on cherries (Prunus spp.) and evergreens. Eastern tent caterpillars (Malacosoma americanum) are emerging and making webs at the crotch of cherries.

Like last week, weedy plants such as hairy bittercress (Cardamine hirsuta), mouse-ear cress (Arabidopsis thaliana), common chickweed (Stellaria media), common whitlowgrass (Draba varna), red deadnettle (Lamium purpureum), sheep sorrel (Rumex acetosella), grape hyacinth (Muscari botryoides), and dandelions (Taraxacum sp.) are blooming. In addition, thyme-leaved speedwell (Veronica serpyllifolia) and white clover (Trifolium repens) have begun blooming.

Several invasive plants are noticeable around the landscape. Callery pear (Pyrus calleryana) is still blooming. Japanese barberry (Berberis thunbergii) and garlic mustard (Alliaria petiolata) have begun blooming. Japanese knotweed (Reynoutria japonica) is sending up shoots. Oriental bittersweet (Celastrus orbiculatus) and autumn olive (Elaeagnus umbellata) are leafing out.

Be on the lookout for paper wasps (Polistes spp.) and yellowjackets (Vespula spp. and Dolichovespula spp.). They will start building nests soon. They tend to prefer shaded areas, such as eaves of houses or shrubs.

Ants are very active. Carpenter ants (Camponotus spp.) have been reported making their way into many homes in the area.

Deer ticks (Ixodes scapularis) and American dog ticks (Dermacentor variabilis) continue to be active. Nymphal deer ticks, which are responsible for most cases of Lyme disease, are active right now.

Blake Dinius, Entomologist with Plymouth County Extension, reporting from the Plymouth area.

North Shore (Beverly)

General Conditions: 

Temperatures during this week's reporting period were variable. Day temperatures ranged from 53ºF to 78ºF, and nights ranged from 41ºF to 56ºF. The average daily temperature for this period was 54ºF with the maximum of 78ºF recorded on May 5 and minimum of 41ºF recorded on May 4.

Approximately 0.14” of rainfall was recorded at Long Hill, on April 30, during this period. Because of dry and pleasant weather, gardening activities are in full gear in the area. Many groups are also organizing plant sale events to take advantage of good gardening weather.

Multiple plant species continue to be in full bloom, and others are beginning to bloom. Woody plants in full bloom include mountain pieris (Pieris floribunda), canary weigela (Weigela subsessilis), burkwood viburnum (Viburnum burkwoodii), flowering dogwood (Cornus florida), redbud (Cercis canadensis), allegany serviceberry (Amelanchier laevis), large fothergilla (Fothergilla major), royal azalea (Rhododendron schlippenbachii), common lilac (Syringa vulgaris), Kwanzan cherry (Prunus serrulata), Elizabeth magnolia (Magnolia ‘Elizabeth’), crabapple (Malus spp.), hardy orange (Poncirus trifoliata), Olga Mezitt rhododendron (Rhododendron ‘Olga Mezitt’), and highbush blueberry (Vaccinium corymbosum).

Non-woody plants seen in bloom include daffodil (Narcissus spp.), forget-me-not (Myosotis sylvatica), tulips (Tulipa spp.), Asian bleeding heart (Lamprocapnos spectabilis, formerly Dicentra spectabilis), Siberian iris (Iris sibirica), trillium (Trillium grandiflorum), vinca (Vinca minor), and honesty plant (Lunaria annua).

Pests/Problems:

Leaf spots, probably caused by fungus Pseudocercospora (formerly known as Cercospora), were observed on rhododendron leaves. Rake and destroy fallen leaves and avoid overhead irrigation. 

Probable colletotrichum leaf spot of daylily was observed on some daylilies. Colletotrichum leaf spot is caused by the fungus Colletotrichum dematium and causes leaf tissue to die in a streak along the mid-vein. Remove infected leaves and destroy leaf debris at the end of the season. Avoid overhead irrigation.

Native holly leaf miner (Phytomza ilicicola) was observed on American holly (Ilex opaca). Gather and destroy leaves that drop prematurely to reduce the adult population.

Weeds are thriving in some lawns and landscapes. Weeds seen in bloom include dandelion (Taraxacum officinale), ground ivy (Glechoma hederacea), common blue violets (Viola spp.), garlic mustard (Alliaria petiolata), and purple deadnettle (Lamium purpureum).

Ticks are active. Be careful to protect yourself with tick repellent when working outdoors and check yourself thoroughly after being outdoors in the woods or tall grasses.

Geoffrey Njue, Green Industry Specialist, UMass Extension, reporting from the Long Hill Reservation, Beverly.

East (Boston)

General Conditions: 

Over the past week daytime temperatures averaged 62ºF, with May 4 and 5 reaching 73ºF and 79ºF respectively. Overnight temperatures averaged 44ºF.

We received 0.23” of precipitation. April's total rainfall was 1.42”.

Plants continue to leaf out and insect activity is increasing. The common lilac (Syringa vulgaris) plus Syringa ‘Sensation’ and Syringa x oblata ‘Betsy Ross’ are in full bloom. The distinct yellow flowering Magnolia x ‘Elizabeth’ is in bloom. Beneficial lady beetles are feeding on aphids.

Pests/Problems:

Lack of adequate precipitation is a concern in non-irrigated landscapes. The consecutive 70ºF windy days have put stress on plants as they continue to leaf out and flower.

Lace bug (Stephanitis takeyai) is active on the underside of Japanese andromeda (Pieris japonica) foliage. There is visible yellowing and stippling to the leaves. Mountain andromeda (Pieris floribunda) is a recommended, resistant replacement.

Azalea bark scale (Acanthococcus azaleae) is active on susceptible plants. The white soft scales are visible on trunks and branches. They produce honeydew which often leads to infestations of sooty mold.

Snowball aphids (Ceruraphis viburnicola) are feeding on emerging leaves of Koreanspice Viburnum (Viburnum carlesii). The young leaves are showing signs of deformation and curling.

Kit Ganshaw & Sue Pfeiffer, Horticulturists, reporting from the Boston area.

Metro West (Acton)

General Conditions: 

Weather for this past week has certainly been typical for this time of the year and very spring-like with the cool mornings and warm afternoon temperatures, gusty winds, and rainy, damp days. For this past week, a high temperature of 72°F was recorded on May 4 and a low of 32°F was recorded on May 4 as well.

The average rainfall total for the month of April is 4.16” and I closed out the month for this metro west area with a total of 1.68” of rain recorded. The average rainfall total for the month of May is 3.37” and the total precipitation recorded for the month so far is 0.04”.

Despite the lack of April showers, there is still much in bloom, including common flowering quince (Chaenomeles speciosa), Carol Mackie daphne (Daphne x burkwoodii ‘Carol Mackie’), large fothergilla (fothergilla major), sweet woodruff (Gallium odoratum), highbush blueberry (Vaccinium corymbosum), and burkwood viburnum (Viburnum x burkwoodii).

Pests/Problems:

Weather alerts for elevated fire risks were broadcast throughout the area and beyond in the earlier part of the week. The potential is high due to the lack of rainfall, strong winds gusts, and low humidity.

One of our most invasive herbaceous weeds of all time, garlic mustard (Alliaria petiolata), is in full bloom and can be easily spotted because of its white flowers. It is seen growing anywhere and everywhere, including on roadsides and in woodlands, wetlands, and gardens.

Julie Coop, Forester, Massachusetts Department of Conservation & Recreation, reporting from Acton.

Central Region (Boylston)

General Conditions: 

Temperatures averaged around 63.6°F; the lowest night temperature was 39°F on May 3. A record high was hit on May 5, being 84°F.

Recorded precipitation within this report period was 0.17”, the majority falling on April 30.

Herbaceous material that can be seen in bloom are moss phlox (Phlox subulata), goldenseal (Hydrastis canadensis), foam flower (Tiarella cordifolia), barren strawberry (Waldsteinia fragarioides), trillium (Trillium spp.), violets (Viola spp.), bishop's-cap (Mitella diphylla), Dutchman's-breeches (Dicentra cucullaria), wood poppy (Stylophorum diphyllum), eastern bluebells (Mertensia virginica), and bishop's hat (Epimedium spp.).

Woody material that can be seen in bloom are chokecherry (Prunus virginiana), apple/crabapple (Malus spp.), Koreanspice viburnum (Viburnum carlesii), and fothergilla (Fothergilla spp.).

Pests/Problems:

Precipitation is still very little. Conditions have been very dry, and the central region is still within level 1 mild drought status. Fire risk alerts were also sent out, with high winds accompanying the dry conditions.

Rabbits continue to be seen foraging any emerging green material, mowing down strawberry groundcover and its flowers (Fragaria virginiana) especially.

Our native tent caterpillar (Malacosoma americanum) can be seen forming nests on different woody material.

Ticks have been particularly bad this spring, with the winter seeming to have no negative effects on their productivity.

Swaths of dandelions (Taraxacum officinale) can be seen throughout the landscape, along with garlic mustard (Alliaria petiolata). It is perfect time for physical removal of these species, for the size ensures that the whole root can be taken as the plant is pulled.

Anna Petrie, Plant Recorder, and Steven Conaway, Director of Horticulture, reporting from New England Botanic Garden at Tower Hill, Boylston.

Pioneer Valley (Amherst)

General Conditions: 

The glory of spring continues across the Pioneer Valley as we settle into May. There is so much new growth and color right now across the landscape that it’s almost impossible to keep up. Yet, if it wasn’t for the unseasonably warm temperatures in mid-April, we could be experiencing a late spring, with the persistence of cold nights in the 30s over this past reporting period.

April rainfall totals for the tri-counties were nothing to write home about, aside from a few locations. Totals ranged from 2.4–4.1” in Franklin County, 2.3–2.5” in Hampshire County, and 2.0–3.2” in Hampden County. The forecast at the time of writing calls for various showers in the extended forecast, so hopefully some respectable accumulations develop. With the showers last week and cool to mild temperatures, soil moisture remains okay in most locations. That said, new plantings should be closely monitored and watered as needed throughout the growing season. The small root zone of many transplanted trees can be shielded by the canopy from rainfall and overhead sprinklers, so be sure to hand check the soil.

Spring is often a very windy time in the Connecticut River Valley but aside from this past week (especially May 4-5) the spring winds have been less prominent this year. Mosquitoes and black flies are out, and the consensus is that tick populations are very high. Pollen levels continue to ramp up with oaks and hemlocks dispersing pollen, among many other trees and shrubs.

Pests/Problems:

The scattered rain showers, cloud cover, and recent strong winds were ideal for spreading fungal spores over this past reporting period. Of note, the orange and gelatinous spore masses of cedar-quince rust (Gymnosporangium clavipes) and cedar-apple rust (Gymnosporangium juniperi-virginianae) have been abundant on eastern red-cedar (Juniperus virginiana) and other Juniperus hosts. While cedar-apple rust can occasionally be a problem, cedar-quince rust can be very damaging to both red-cedar/juniper and rosaceous hosts like serviceberry (Amelanchier) and hawthorn (Crataegus). While the cedar-apple rust pathogen produces galls on juniper needles, cedar-quince rust galls form on twigs and branches. When abundant, they girdle these tissues resulting in serious canopy dieback. The fungal cankering pathogen Diplodia can also be readily found on Juniperus with cedar-quince rust infections, furthering the dieback.

As noted last week, pine tip moth damage has been observed on several pines (Pinus) across Hampshire County this spring. Pictured here is damage from a pine tip moth larva (Rhyacionia sp.) on the developing candles of a mugo pine (P. mugo) on the UMass campus. Two species are problematic in the region, the European pine shoot moth (R. buoliana) and Nantucket pine tip moth (R. frustrana). Continue to scout hard and soft pines for this destructive pest. Small green caterpillars can be found on various deciduous hardwoods, although identifying them is much more challenging than finding them. Bruce spanworm (Operophtera bruceata) is a native moth that may be the culprit in some cases. In general, its presence does not warrant our time and energy but if numerous, it can be treated.

According to the UMass Fruit Team, the rainfall on May 6 will result in significant apple scab (Venturia inaequalis) infections across the area. We are also entering the period of fire blight (Erwinia amylovora) infections on apple (Malus) and pear (Pyrus).

Nick Brazee, Plant Pathologist, UMass Extension Plant Diagnostic Lab, reporting from Amherst.

Berkshire Region (West Stockbridge)

General Conditions: 

This past week brought typical spring variability in temperature and weather patterns. We recently had a high of 79°F on May 5 with significant wind later in the day as a forecasted period of rain approached. As of this writing, we are in the middle of a much-appreciated gentle soaking rain. Earlier, Saturday May 3 was pleasantly sunny and crisp, but the temperature never rose above 52°F. There was a low of 31°F reported on May 3 but it didn't seem to do any harm.

A walk in the Berkshire woods at this time is magical with spring ephemerals in bloom or in bud. Recent sightings include both the painted trillium (Trillium undulatum) and red trillium (Trillium erectum), bluets (Houstonia caerulea), various species of violets (Viola spp.) including the sweet white violet (Viola blanda), and northern starflower (Lysimachia borealis) all in full bloom. Canada mayflower (Maianthemum canadense) and bluebead lily (Clintonia borealis) are in bud.

In the garden, the later daffodils are still putting on a show with tulips joining the spring bulb display. The fern leaf peony (Paeonia tenuifolia) is blooming, as is globeflower (Trollius spp.) Virginia bluebells (Mertensia virginica), Soloman's seal (Polygonatum spp.), primrose (Primula spp.), and much more. Shrubs in bloom include fothergilla (Fothergilla x intermedia), viburnum (Viburnum carlesii), and yellowroot (Xanthorhiza simplicissima).

Pests/Problems:

Mosquitos and black flies are becoming increasingly prevalent, and deer ticks (Ixodes scapularis) are active and numerous.

Voles, deer and rabbits are continuous pests.

The eastern tent caterpillar (Malacosoma americanum) has been spotted frequently.

Weeds in bloom include cow parsley (Anthriscus sylvestris), dandelion (Taraxacum officinale), chickweed (Stellaria media), ground ivy (Glechoma hederacea), garlic mustard (Alliaria petiolata), cuckooflower (Cardamine pratensis), and bitter wintercress (Barbarea vulgaris).

Eric Ruquist, Director of Horticulture, reporting from Berkshire Botanical Garden, Stockbridge.

Landscape Pest Reports

Diseases

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

Insects and Other Arthropods

Are you a professional (landscaper, arborist, municipal employee, tree warden, pest management professional, etc.) managing insect & mite pests of trees & shrubs in Massachusetts? Please consider joining our Tree & Shrub Insect & Mite Pests of Massachusetts Collection Project on iNaturalist! 

Here's how to participate:

• Use your existing iNaturalist account or create a new iNat account using a valid e-mail address, creating a unique username & password.
• Visit the Tree & Shrub Insect & Mite Pests of Massachusetts Collection Project and navigate either to the "join" or "join this project" area. Further instruction on how to join an existing project are explained on iNatHelp.
• Take up-close & in-focus photos of insect & mite pests on trees & shrubs you are currently managing (as a regular part of your monitoring activities). You can take multiple photos of the same observation - including images of any life stages that are present as well as the feeding damage seen on the tree or shrub. A smart phone works just fine to make and upload observations. (Mites may require magnification.)
• Start uploading your observations of insect & mite pests on trees & shrubs in Massachusetts. At this time, the project should automatically collect & include your observations, as long as you start identifying what you've found and note your location in MA. (See the project description for more information on obscuring location data for privacy, while still being able to participate.)

Please upload any monitoring data you collect throughout the 2026 growing season. This information may help us to identify native pest outbreaks on trees and shrubs, non-native pests on trees & shrubs, increase stakeholder engagement, and inform the creation of pertinent educational materials. We hope to see you on iNat!

The Professional Insect and Mite Management Guide for Woody Plants is freely available. The online, searchable guide is for professionals managing the health of trees and shrubs in Massachusetts, although the insect and mite species mentioned within may be applicable to much of New England. Search for information about over 200 pest species, native and introduced, using common and scientific names, host plants, and growing degree days. Information about pest identification and life cycles as well as integrated pest management options are included.

Please let me know how it works or isn’t working for you using this feedback form. Your response is valuable, and I cannot wait to hear from you!

2026 Updated Resources:

• Monthly Insect Almanacs: Track pest insect activity on trees and shrubs in Massachusetts seasonally with monthly insect almanacs. Pest life cycles vary throughout the growing season and so do professional options for management. Consider this pest itinerary when planning. It is a new resource within the Professional Insect and Mite Management Guide for Woody Plants. It is not meant to replace site-specific monitoring or growing degree day tracking.
• Insects Added to the Professional Insect & Mite Guide:
  • Imported Longhorned Weevil
  • Gouty Oak Gall Wasp
  • Horned Oak Gall Wasp
  • Hickory Tussock Moth

Introduced (Invasive) Species Updates:

• Asian Longhorned Beetle is still a concern in Worcester, Shrewsbury, Boylston, West Boylston, and parts of Auburn, MA. The 12.3 square miles of Holden, MA that were originally part of the regulated area for ALB has been removed as of 2025.

  If you suspect you’ve found this insect or the damage it causes, particularly on maple, there are many ways to report it depending on your location:

  1. If in Massachusetts: please report suspicious insects or damage to host plants to the Asian Longhorned Beetle Eradication Program office in Worcester, MA at 508-852-8090 or visit the Massachusetts Introduced Pests Outreach Project.
  2. All US states outside of MA: please visit the USDA APHIS Asian Longhorned Beetle page.

• Box Tree Moth has been detected in some communities in Barnstable County, MA as well as Norfolk County, MA in the community of Brookline. A map of these locations is available courtesy of the MA Department of Agricultural Resources. If you believe you have found this insect, please take a photo, note your location, and report it to the Massachusetts Introduced Pests Outreach Project. *MDAR has an excellent new box tree moth short video alert available.

Box tree moth caterpillars that overwinter are now active where this insect occurs in Barnstable County, MA. Refer to the Cape Cod Region (Barnstable) report by Russ Norton, above, for updates about this pest throughout the season. 

• Elm Zigzag Sawfly has been detected in various communities in Massachusetts. A map of where elm zigzag sawfly has been confirmed in MA is available. If you believe you have found this insect, please take a photo, note your location, and report it immediately using the Massachusetts Elm Zigzag Sawfly Reporting Form.

• Spotted Lanternfly now has established populations in multiple communities in Massachusetts. If you believe you have found this insect, please take a photo, note your location, and report it immediately to the Massachusetts Introduced Pests Outreach Project. 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.

Spotted Lanternfly egg hatch is expected to occur in the coming weeks. Monitor overwintered egg masses from last season for the presence of early instar nymphs. Immediately upon hatching, the immature lanternflies may appear white in color. Within approximately an hour, first instar nymphs become black with white spots. A great timelapse video of spotted lanternfly egg hatch and the color change observed in the nymph is available at Bug of the Week by Dr. Michael Raupp.

Medically Important Pests:

• Mosquitos and the diseases they vector are also a serious public health concern in Massachusetts by summer. Available resources include Mosquito Repellents from the Massachusetts Department of Public Health and Preventing 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. Beginning in June, risk maps with details about mosquito activity will be available through the MA Department of Public Health. 

• Stinging Insects such as bees and wasps are awakening from their overwintering shelters on mild, sunny spring days!

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

Tree & Shrub Insect & Mite Pest Suggested Scouting:

• Andromeda Lace Bug is most commonly encountered on Japanese Andromeda. Eggs are tiny and inserted into the midveins on the lower surface of the leaf and covered with a coating that hardens into a protective covering. 5 nymphal stages are reported. Nymphs are different in appearance from adults, often covered with spiky protrusions. 3-4 generations per year have been observed in New England, with most activity seen between late-May into September.

• Arborvitae Leafminer mature caterpillars are found roughly from April to June and fully grown caterpillars overwinter in mined host plant leaves. Pupation occurs the following spring and adults emerge, and females lay eggs.

• Ash Plant Bug eggs are laid in cracks and crevices of host bark in the fall, where they overwinter. Eggs hatch in mid-May. Nymphs crawl to the undersides of the leaves where they will feed. Adults of the first generation will lay eggs on the midveins of the leaves in the summer (July) and eventually hatch to produce the second generation of nymphs. Second generation plant bugs will feed on the underside of leaves until killed by the frost, laying the eggs that overwinter on host bark.

• Azalea Lace Bug native to Japan, deposits tiny eggs on the midveins on leaf undersides. Look for dark, black tar-like spots of excrement deposited by immature and adult lace bugs on the underside of susceptible host plant leaves, especially on leaves with white-yellow stippling visible on the upper surface. If lace bugs are not already known to the location, check susceptible hosts located in full sun first. Monitor plants for lace bug feeding from late April through the summer.

• Bagworm is overwintering on Juniperus spp., Thuja spp., Quercus spp., Platanus spp., and others as 500-1000 eggs found in the bags of last season’s deceased females. Now is the time to remove and destroy overwintering bags of eggs, prior to egg hatch at approximately 600 GDD’s (approx. mid-June).

• Boxwood Mite feeds on upper and lower leaf surfaces of Buxus spp. hosts. Overwintered eggs hatch into larvae in the spring, which mature into nymphs and eventually adults. The entire life cycle takes approximately 18-21 days. Most feeding injury occurs in the spring, and hosts may appear off-color.

• Boxwood Psyllid nymphs feed on Buxus spp. developing buds and leaves. Upward cupping and yellow of leaves can be a sign of previous or current season’s damage.

• Cankerworms can be found feeding on similar host plants in the spring, despite fall and spring cankerworm being different species of insects. Spring cankerworm adult moths are active in February and March, laying masses of 100 or so eggs in the rough bark of larger branches or the trunk of the host plant. Fall cankerworm adults have already laid their masses of eggs on host plant branches and twigs, back in late November and early December of last year (sometimes the current year’s January). Egg hatch of both species occurs by approximately mid-May, with caterpillar feeding through roughly the end of June.

• Carpenter Ants are called carpenter ants as they seek out soft wood to make a nesting place for their brood or young. Nests may be found in the interior of living trees, including sugar maple, sweetgum, Prunus species, northern white cedar, and balsam fir. They may be also found in standing dead trees, stumps, or wooden structures that are in a state of decay. While these insects do not feed on trees, the activity of them creating galleries and nesting locations for their brood can sometimes weaken the core of the tree and potentially make it hazardous.

• Cooley Spruce Gall Adelgid typically overwinters as an immature female near spruce twig terminals. By early spring, this female matures into a stem mother which will lay hundreds of eggs on lateral terminals. Following egg hatch, nymphal feeding induces gall formation on spruce hosts. Green galls on spruce may be removed and destroyed. On Douglas fir, the Cooley spruce gall adelgid’s alternate host, look for woolly masses in the spring and distorted or crooked needles. Do not plant spruce and Douglas fir close together when possible.

• Dogwood Borer feeds as a larva on the phloem and cambium of their host plants. When dogwood flowers begin to drop, adult dogwood borer moths begin to emerge. Moth flight and activity can last through September. That being said, it is best to combine phenological indicators, growing degree day tracking, and pheromone trapping to accurately monitor this insect and time treatments. Research has suggested that emergence times for dogwood borer adult moths differ regionally and by host plant.

• Eastern Spruce Gall Adelgid overwinters as a partially grown female, maturing into a stem mother by early spring. Stem mothers lay 100-200 eggs by budbreak. Eggs hatch and nymphs feed on the needles of their Picea spp. hosts. As green galls develop, prune out and destroy when possible.

• Eastern Tent Caterpillar eggs have hatched and young caterpillars have begun to feed on expanding cherry foliage. Look for ever growing silken tents around groups of feeding caterpillars as the season continues. Tents are often placed where branches join.

• European Pine Sawfly eggs have overwintered in slits in last year’s needles. Egg hatch begins in approximately late-April and early May, with larvae feeding on previous year's needles until approximately late-May or early June, at which time they drop to the ground to pupate.

• European Pine Shoot Moth may refer to at least three species of native moths in the Northeast. The yellowing of the tips of twigs or the clear deposits of pitch between new bud clusters may be early signs of activity of this insect on Pinus spp. hosts. Mined needles will die and turn brown in color, which can be noticed in the summer. Initial areas of wounding are covered with resin-coated webbing. By the middle of the summer, the larvae move to the buds and burrow into them. Scaring is often caused. In August, feeding stops and tiny, black caterpillars overwinter in this area covered by the resin-coated webs.

• Fletcher Scale is a pest of arborvitae, juniper, yew and others. Second instar nymphs (immatures) overwinter. They begin to mature in May and females will lay (500-600; but up to 1000) eggs beneath their bulbous bodies by late May and early June. During this time of development in the spring, plant damage and honeydew may become especially obvious, particularly on yew. Sooty mold may grow on the honeydew. 

• Forest Tent Caterpillars will feed together in groups when caterpillars are still small but may wander individually as they mature. Caterpillars may reach up to 2 inches in length and are blue and gray with oval white spots down the back that are sometimes described as "key holes" or "tiny penguins". They do not create tents, unlike the common name suggests.

• Four-Lined Plant Bug feeds on over 250 plant species, many of which are herbaceous. The four-lined plant bug overwinters as eggs which are inserted into the tender shoots or water sprouts of certain host plants. Females use their ovipositor to cut a slit in the tissue of the plant, into which the eggs are inserted. Egg hatch may occur in late April or May in Massachusetts. Nymphs develop over the course of approximately 30 days. Feeding injury from both the nymphs and adults causes black or brown disease-like spots to form on the foliage of numerous hosts. The injured areas may turn black or appear translucent. After a few weeks, the necrotic tissue may drop from the plant leaving small holes behind.

• Fruitworms is a complex of at least 10 species that are sometimes collectively referred to as "fruitworms" or "green fruitworms". These are native insects that feed on similar hosts at the same time and cause similar feeding damage. Eggs hatch and young larvae crawl to the opening buds of their host plants and begin to feed, usually beginning around April or May in Massachusetts. Caterpillars mature as the leaves of their host plants mature. Fruitworm caterpillars may be observed feeding on their hosts until approximately the end of June.

• Hackberry Psyllid may refer to at least 10 species of psyllid in the genus Pachypsylla that are reported on hackberry. When new hackberry leaves begin to unfold from the buds, mating and egg laying by these species will occur over the next few weeks. Eggs hatch in approximately 10 days and the nymphs (immatures) will begin to feed on the leaves. Depending on the species, a blister or a nipple gall is formed on the leaf in response to the insect's feeding. 

• Hemlock Looper collectively refers to two species of geometrid (inchworm; looper) caterpillars. Overwintered eggs hatch by late May or early June, at which time young larvae begin their messy feeding on host plant needles. Hemlock and balsam fir are preferred hosts.

• Hemlock Rust Mite feeds on the needles of its hosts by removing fluids from the needles. When mite populations are high, foliage may appear blue-ish in color and turn yellow before dropping from the plant. The hemlock rust mite causes most of its damage in the spring and may be a pest in nurseries. Damage by this eriophyid mite is most noticeable by mid-summer, but by that time the populations typically die off.

• Holly Leafminer is an introduced from Europe and feeds only on Ilex aquifolium. The damage this species causes, as well as its biology, are both similar to our native holly leafminer (P. ilicicola) which is discussed below. The main difference in the life cycle is that the European holly leafminer lays its eggs in the midvein of the leaf. The young larvae then tunnel in the midvein until the fall. One generation occurs per year. Larvae overwinter in their leaf mines, pupating in March or April. Over an approximately 6-week period, the adult flies emerge in the spring. This may begin after new leaves have formed on the host. Adults are tiny, black flies approximately 1/8 inch in length. In approximately 10 days, adult females lay their eggs in the leaf midveins. Larvae are yellow maggots and up to 1.5 mm. when fully grown. Larvae feed slowly, and current year's mines may be easily overlooked.

• Honeylocust Plantbug is one of the most impactful (of at least 7 species of) plant bugs on this tree species. There is one generation per year and this insect overwinters as eggs laid just beneath the bark surface of 2 and 3 year old twigs. Eggs hatch once the buds of honeylocust begin to open. Young nymphs will move to the freshly opening leaves and begin to feed. Nymphs (immatures) are pale green with short wing buds that do not extend to the end of the abdomen. The majority of the feeding damage from this insect occurs at this time, while leaves are still very small and the insect is well hidden. 

• Hydrangea Leaftier  is a moth in the Family Tortricidae whose caterpillars use silk applied to the edges of two newly expanding hydrangea leaves to tie them together to create an envelope-like structure within which they feed. These leaf-envelopes tend to occur near the tips of plant stems and can be very obvious. As a result, the two tied leaves may not fully expand when compared to healthy, non-impacted leaves. Pupation is thought to occur in the ground nearby host plants, so the insect drops to the ground to pupate where it overwinters. Pupation occurs sometime in June. Adults are found in the spring and are small white and brown moths; the white patterns somewhat resemble bird droppings, aiding in camouflage from bird predation. 

• Imported Willow Leaf Beetle adults overwinter in loose bark or other sheltered areas near susceptible Salix and Populus spp. host plants. Adults are active and feed and lay tiny, yellow eggs in clusters on leaf undersides. Additional resources include an InsectXaminer episode about imported willow leaf beetle.

• Juniper Scale is native to Europe and is now found throughout the United States. The overwintering life stage are adult females, which can be found on the needles of the host plant, filled with yellow eggs. By late May or early June (in Connecticut, New Jersey, and Ohio) crawlers appear. Monitor susceptible host plants for off-color foliage. Examine needles using magnification (10X hand lens) for tiny, circular, white female scale covers. Observe scale covers for the evidence of natural enemy activity (ex. exit holes from parasitoids).

• Larch Casebearer is an introduced species from Europe. Fully grown larvae are approximately 6 mm in length. By late May or June, larvae complete their feeding and pupate within their case. Adults emerge by June and early July and are winged to disperse.

• Lily Leaf Beetle, while not a pest of trees and shrubs, can be an important insect found in ornamental landscapes. Bright red overwintered adult beetles mate and lay eggs by May. 250-450 eggs may be laid per female. Additional resources include an InsectXaminer episode about lily leaf beetle.

• Magnolia Scale overwinters as nymphs (immatures) found on 1 and 2-year old twigs of the host plant. Nymphs begin feeding as temperatures warm in the spring, molting once by late April or May and again by early June.

• Native Holly Leafminer is one of seven species of leafminers that feed on holly. Phytomyza ilicicola is usually referred to as the native holly leafminer. This species is known to feed on Ilex opaca, I. crenata, and related cultivars; however, it only lays its eggs in American holly (Ilex opaca). Some research suggests that the native holly leafminer may lay its eggs in other Ilex species, but that the larvae are unable to complete their development. This insect is found throughout the native range of its host plants. Larvae overwinter in leaf mines and pupation occurs in March and April and adult emergence by mid-May. Adult flies are known to emerge over a period of 6 or so weeks in the spring. Adults appear by June in Massachusetts. Adults are black and 1.0-1.6 mm long. Females lay eggs using their ovipositor on the underside of newly formed leaves. A tiny green blister forms on the leaf as the first symptom of injury.

• Oak Leaftier caterpillars hatch from eggs in approximately mid-April to early May. The earliest hatched caterpillars are capable of entering the buds of their host plants even prior to their expansion. Any leaves that survive often expand with holes created before they even opened.

• Oystershell Scale eggs hatch from early May to mid-June. Second instar crawlers (immatures) are found from mid-June to late July. Adults from early August to late September.

• Pales Weevil overwintering life stage are the adults who hide at the soil surface or in the leaf litter. Activity resumes in the spring with warming temperatures, typically by late April and early June (in warmer climates, adult activity can occur year-round). Adult beetles are particularly attracted to freshly cut stumps, where egg laying will preferentially occur on the roots.

• Pale Tussock Moth (Banded Tussock Moth) is an eastern United States species that feeds on the foliage of deciduous trees and shrubs. Adult moths are seen in June and July, with females laying egg masses on the underside of host plant leaves in July. The forewings of the adult moths are pale yellow-tan or cream-colored with a checkered pattern with darker bands; the thorax of the adult also possesses a pale orange stripe with thinner turquoise stripes on either side. Eggs hatch and caterpillars feed on host plant leaves beginning in mid-July. Caterpillars feed on the leaf tissue between leaf veins and may be seen resting on upper leaf surfaces. Caterpillars are yellow/brown/tan and hairy, and active until the end of September. Caterpillars have noticeably longer black and white hairs (lashes) extending from either end of the body.

• Peachtree Borer is a clearwing moth pest of ornamental trees and shrubs. In particular, those in the genus Prunus are most impacted. The larvae of this insect feed on the inner bark of the host plants near the root crown and are capable of girdling the tree. Larvae (caterpillars) are cream colored with brown heads. Once mature, following approximately 7 instar stages, caterpillars pupate in their tunnels and the adult moths emerge around early July (records from New York). Adult females lay 200-800 oval, reddish-brown, 1/2 mm long eggs on the trunk or lower branches of their host plants over a period of approximately 6 weeks. Eggs are laid in small groups. Newly hatched larvae of this species, unlike some other species of clearwing moths, are able to chew through the external bark to reach the phloem (Johnson and Lyon, 1991) where they feed.

• Pine Bark Adelgid overwinters in an immature life form, which begins feeding again as springtime temperatures increase. This is the time when the insects begin secreting a white, waxy layer over their bodies. High populations can make the trunks of eastern white pine appear as if coated in snow. Typically, management is not necessary. Syringing (washing adelgids off the trunk of larger trees with a strong jet of water) is an option.

• Pine Spittle Bugs feed on a variety of coniferous and other host plants. "Spittlebug" refers to the habit of the nymphs of these species, which produce frothy liquid around themselves to keep moist and protected from natural enemies. Eggs overwinter. In the spring, the nymphs hatch and begin feeding on host plant twigs. With piercing-sucking mouthparts, the nymphs feed on sap from host plant phloem. Sap is partially digested, whipped into a spittle-like foam, and several nymphs may be found in a single spittle mass. 

• Pitch Twig Moth is a clearwing moth species that will develop in the twigs of pine, particularly pitch pine, of the current year's growth. Eggs of this species are tiny, circular, and yellow when first laid by the adult female moth. Eggs hatch and caterpillars were present in Ohio by June. Early feeding by the caterpillars is completed at the needle bases for 1-2 weeks. Caterpillars molt at least once before then boring into the twigs and feeding, creating a nodule. After a month of feeding, the caterpillars move through the center of the twig and begin feeding on the pith. The feeding done by this insect causes ample resin (pitch) to leak from the initial feeding sites. Resin combined with frass form the characteristic nodule created by the activity of this insect. Nodules are typically found on the upper surfaces of the twigs.

• Privet Thrips adult females lay their eggs on host plant leaves late in the spring, with several generations per year possible through the summer. The number of generations on a single plant may depend upon the food quality of the plant for the thrips following so many generations of feeding. Immature thrips (larvae) are slender and wingless and found with magnification primarily on leaf undersides. Adults are also tiny, 1 mm in length, with wings. The larvae and adults feed and cause chlorosis on host plant leaves, which may be visible to the naked eye as a dusty/gray color.

• Rhododendron Borer is a tiny, native clearwing moth. Adult moth emergence may begin in May and last through July, depending upon local temperatures. After mating, adult females lay their eggs (up to 40 each) near locations of the host plant with defects or injury - particularly, branch crotches, pruning cuts, scars, or old larval feeding galleries. Eggs are tucked into these areas by the females, who perish shortly thereafter. Larvae hatch and chew their way to the inner bark, where they tunnel and feed and fill these tunnels with small, reddish frass pellets. By late fall, the larvae move to the sapwood to overwinter.

• Snowball Aphid overwinters as an egg on the twigs and buds of Viburnum spp. hosts. Egg hatch occurs at the same time host plant buds are opening in the spring. Newly hatched aphids will begin to feed on and distort the newly developing leaves of their hosts. Aphids may be protected from contact insecticides within curled leaves.

• Spruce Spider Mite is a cool season mite which causes most of its feeding damage on coniferous hosts in the spring and fall. Monitor for discolored needles and the mites themselves. Monitoring for spruce spider mite can be done by shaking 3-4 branches over a white piece of paper and viewing mites with a hand lens.

• Taxus Mealybug first instar nymphs are reported as the overwintering life stage in New Jersey. They may be found in bark crevices on the host plant. In April and May few live mealybugs are found. However, by mid-June the population may increase considerably. Adult female taxus mealybugs are present from June to August and give birth to live young in the early summer. Nymphs and adults have been reported in Massachusetts in June, but no eggs or young nymphs were seen at that time in prior studies.

•  Tuliptree Scale is a soft scale pest of Liriodendron and Magnolia spp. among others. Second instar nymphs overwinter, begin feeding as temperatures warm in the spring, and mature into adults by the late spring/early summer.

• Tussock Moths may have many host plants, depending on the species of moth. One example are those that feed on spruce. There are two common tussock moth species in eastern North America that use spruce. Orgyia antiqua (rusty tussock moth) and Orgyia leucostigma (white-marked tussock moth). Both feed on spruce as well as other conifers and deciduous trees and shrubs (shared hosts include hemlock, fir, apple, or cherry). Both lay their eggs on the outside of the cocoon. This photo is of tussock moth cocoons found on the interior branches of a large blue spruce in northern VT on 5/2/2026. The slightly rounded/oblong structures are the cocoons, often with the setae or hairs of the caterpillars woven into them. The pupae were within the cocoons, emerged as adult moths, and deposited eggs on the outside of the cocoon, which overwintered. Use caution handling the cocoons, as the hairs may cause rashes on the skin or allergic reactions.

• Viburnum Leaf Beetle eggs hatch around May and young larvae are approximately 1 mm in length and greenish yellow in color. They may also be off-white, and they lack spots. Larger larvae may appear yellowish-brown or green with black spots and may grow up to ½ inch in length. 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 Pine Weevil adults have already been active. Before June, remove and destroy flagging or crooked leaders on small trees. Affected trees can be pruned and staked to regain single leader dominance. Trees in sunny locations are more apt to be attacked.

• White Prunicola Scale (Pseudaulacaspis prunicola) is a temperate species of armored scale. It is so very closely related to and easily confused with the white peach scale (P. pentagona) that for a very long time, scientists thought each was a single species. Mated adult females are the overwintering life stage. In northeastern Pennsylvania, egg laying began in mid-May, and again in late-July, with crawlers shortly thereafter. Each female laid approximately 27-78 eggs. In points north of Pennsylvania, there are typically 2 generations per year, occurring approximately in early June and early August in central New England.

• Winter Moth caterpillars feed in both flower and foliar buds and, once a bud has been devoured from within, the caterpillar will migrate to other buds and repeat the process. At maturity, the caterpillars will be approximately one-inch-long, whereupon they drop to the soil for pupation. Pupation occurs in late May/early June depending on the geographic location. Areas including Cape Cod are often a week or two behind inland locations. While patchy and noticeable populations of winter moth may exist in eastern MA, overall, this insect is not expected to be in an outbreak status. An update about winter moth populations in Massachusetts is available from UMass Extension's Landscape, Nursery and Urban Forestry program.

• Woolly Apple Aphid overwinters as eggs in the cracks and crevices of Ulmus spp. host plants. As spring temperatures warm, these eggs hatch, and stem mothers begin feeding on developing elm leaves. Their feeding and the feeding of the wingless nymphs they produce causes leaf distortion, and a rosette to form on elm. If no elm are present, the aphids will complete their life cycle on apple year round.

• Woolly Elm Aphid overwinters as eggs hidden in cracks and crevices of elm bark. As leaves unfold in the spring, eggs hatch and young aphids feed on the underside of elm leaf tissue. These aphids mature and give birth to hundreds of additional females. Feeding causes leaves to curl around the aphids. Curled leaves may also turn reddish brown.

Beneficials/Non-Pests:

• Green Lacewings may be seen in their adult stage at this time. Genus Chrysoperla is common in much of the United States. While adult lacewings mostly feed on pollen and nectar, their larvae (immatures) are beneficial predators of aphids, mealybugs, thrips, mites, leafhoppers, whiteflies, caterpillars and other soft bodied insects that are also often pests of ornamental plants. They are beneficial insects that are naturally occurring in our landscapes and should be preserved. Depending upon the species, they may have multiple generations per year.

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

Weeds

Explore UMass Extension's Weed Herbarium, a definitive picture identification guide designed to aid in the management of our most common weed species. 

As forsythia approaches the end of its flowering period, preemergence crabgrass control products for the management of crabgrass and other summer annual grassy weeds should be wrapping up. These preemergence herbicide products are available as on-fertilizer or sprayable formulations. The correct timing of these applications is likely to vary significantly from location to location within specific regions of New England. These applications need to be watered in to be effective; insufficient watering in will result in less than optimal control. Both spray (sprayable formulations) and spread (granular or on-fertilizer formulations) applications that are not watered in sufficiently are essentially the same as the product still being in the jug or the bag, so an application is only completed after it is watered into the turf canopy.

Wild garlic (Allium vineale) is visible in turf and landscape settings now. Other common names include field garlic, crow garlic, stag's garlic and on rare occasions, wild chives. Visit the Weed Herbarium to see images and identification characteristics. Managing this species in turf and landscapes is often unnecessarily difficult for professionals as herbicide control can be very effective. Like garden onions, wild garlic has a very waxy leaf. This wax results in a large amounts of applied herbicide running off the leaf with little or no plant uptake. When growing in turf, a broadleaf turf herbicide will control wild garlic. In landscape areas, a directed-spray treatment of glyphosate will be effective. To overcome the “waxy-leaf-herbicide-runs-off” problem it is best to step on or roll the plant prior to treatment. This will lay it horizontally so less herbicide spray will run off the leaves and results in some mild wax disturbance which will also improve herbicide absorption.

Garlic mustard (Alliaria petiolata): This biennial weed is considered invasive in Massachusetts and other states. Second year plants are beginning to actively grow, and first-year plants have begun to germinate. Herbicide applications can begin now.

Japanese knotweed (Fallopia japonica): Do not attempt to control Japanese knotweed now, as herbicide applications are not effective in the early part of the growing season. Stay tuned to the Landscape Message for more management information as the season progresses.

A member of the lily plant family (Liliaceae), star-of-Bethlehem (Ornithogalum umbellatum) is currently apparent in some turf and landscape areas. Visit the Weed Herbarium for photos and characteristics. Star-of Bethlehem can be difficult to control but can be managed with glyphosate. Non-chemical, burn-down herbicides (acetic acid, d-limonene, clove oil) will desiccate the leaves and will gradually weaken the bulb of this weed with repeated applications over time. Star-of Bethlehem is also very susceptible to the broadleaf turf herbicide sulfentrazone. Sulfentrazone is found in several 2-, 3- and 4-way broadleaf turf herbicide combinations and in combination with carfentrazone in the herbicide Dismiss NXT. Sulfentrazone alone can be found in several post-patent, generic products. Consult with your distributor about the product options available.

Early season control of woody invasive plants can be very effective. Basal bark or cut-stem application of glyphosate or triclopyr can be used for the management of buckthorn, oriental bittersweet, and Norway maple.

Miscanthus sinensis (Chinese silver grass, eulalia, or maiden grass) is now considered to be invasive in Massachusetts. As of December 8, 2025, the import and propagation of this species is prohibited in Massachusetts, and all sales will become prohibited on December 31, 2026. Information on deadlines for importation, propagation and sale of Miscanthus sinensis and other recently listed species can be found at the Massachusetts Department of Agricultural Resources’ Massachusetts Prohibited Plant List.

Reported by Randy Prostak, Weed Specialist, UMass Extension Landscape, Nursery, & 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, Total Carbon, Total Nitrogen and Soilless Media. The lab is also accepting samples for Plant Tissue analysis, including macro and micronutrients, total carbon, and total nitrogen. 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 on our website.

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
• Stakeholders like you! The Landscape Message is partially supported by educational program user fees and support from readers.