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Landscape Message: May 12, 2023

Landscape Message: May 12, 2023
May 12, 2023
Issue: 
5

UMass Extension's Landscape Message is an educational newsletter intended to inform and guide Massachusetts Green Industry 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.

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


Scouting Information by Region

Environmental Data

The following data was collected on or about May 10, 2023. 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 2023 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

GDD

Soil Temp
(°F at 4" depth)

Precipitation
(Gain since last report)

Time/Date of Readings

(Gain since last report)

2023 Total

Sun

Shade

CAPE 37 132 57 52 0.10 12:00 PM 5/10/2023
SOUTHEAST 33 143 69 55 0.18 3:00 PM 5/10/2023
NORTH SHORE 34 101 54 48 0.03 10:00 AM 5/10/2023
EAST 41 146 67 56 0.25 4:00 PM 5/10/2023
METRO 36 123 59 52 1.10 6:00 AM 5/10/2023
CENTRAL 36 135 59 52 0.27 3:45 PM 5/10/2023 
PIONEER VALLEY 33 135 58 53 0.17 12:00 PM 5/10/2023
BERKSHIRES 16 109 54 48 0.23 8:00 AM 5/10/2023

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.
Rhododendron carolinianum (Carolina rhododendron) Begin * Begin/Full Begin * Begin/Full Begin/Full *
Rhododendron catawbiense (catawba rhododendron) * * * * * * * *
Spiraea x vanhouttei (Vanhoutte spirea) Begin/Full n/a * Full Full Full Full Begin
Elaeagnus umbellata (autumn olive) Begin Full Full Full Full Full Full *
Syringa vulgaris (common lilac) Begin/Full Full Full Full Begin/ Full Full Full Begin/Full
Cornus florida (flowering dogwood) Begin Full/End Full Begin/Full Begin/ Full Begin/Full Full Full
Rhododendron spp.(early azaleas) Begin/Full Full Full Begin Begin/ Full Full Full Full
Malus spp. (crabapple) Full Full/End Full Full/End Full/End Full Full Full
Cercis canadensis (redbud) Full Full/End Full Full/End Full/End Full Full/End Full

Regional Notes

Cape Cod Region (Barnstable)

  • General Conditions:The average temperature for the period from May 3rd thru May 10th was 54ºF,  with a high of 74ºF on May 7 and a low of 37ºF on May 9.  On the mornings of May 9th & 10th there was a possibility of frost occurring in some low-lying areas such as cranberry bogs.  The period had more mostly-sunny days than mostly-cloudy days.  During the period precipitation was insignificant with 1/10th of an inch.  Soil moisture is short. Herbaceous plants seen in bloom include tulips, creeping phlox (Phlox stolonifera), barrenwort (Epimedium spp.), fringed bleeding heart (Dicentra eximia), basket of gold (Aurinia saxitilis) and solomon’s seal (Polygonatum odoratum).  Woody plants in bloom include Japanese cherry (Prunus serrullata ‘Kwanzan’) and koreanspice viburnum (Viburnum carlesii), blueberry (Vaccinium corymbosum), and aronia (Aronia melanocarpa).  Oaks in the red oak group are flowering, the white group are just beginning to flower.  
  • Pests/Problems: Winter moth and likely some fall cankerworm caterpillars can be found feeding on various woody plants, causing some holes in the leaves.  Eastern tent caterpillars are active on black cherry (Prunus serotina), viburnum leaf beetle damage was observed on arrowwood viburnum (Viburnum dentatum).  Slug damage was observed on bearded iris (Iris germanica).  Disease symptoms or signs observed during the period include tulip fire on tulip, leaf spot on ink berry (Ilex glabra), leaf spot on mountain laurel (Kalmia latifolia), shothole disease on cherry laurel (Prunus laurocerasus), sycamore anthracnose on sycamore (Plantanus occidentalis) and cedar apple-rust teliohorns on eastern red cedar (J. virginiana). Winter injuries are still a popular topic.  Bigleaf hydrangea (H. macrophylla), and to a lesser extent mountain hydrangea (H. serrata), were damaged by the extreme low temperatures on February 4th of around -8ºF.  The freeze injured stems resulting in death to buds and overwintering flower buds.  At this point stems can be pruned back in many cases near ground level or to a point of healthy buds.  Butterfly bush has also experienced severe damage also being killed to ground level.  Other injuries on needled evergreens and broadleaved evergreens are still being observed as well.  Weeds seen in bloom during the period include autumn olive (Eleagnus umbellatum), bush honeysuckles (Lonicera spp.), garlic mustard (Alliaria petiolata), common cinquefoil (Potentilla simplex), dandelion (Taraxacum officinale), corn speedwell (Veronica arvensis), thymeleaf speedwell (Veronica syrpyllifolia) deadnettle (Lamium purpureum), and common violet (Viola papilionacea), yellow rocket (Barbarea vulgaris) and cypress spurge (Euphorbia cyparissias). Ticks are active – keep yourself protected!  Rabbits are feeding on emerging perennials.

Southeast Region (Dighton)

  • General Conditions: The average temperature over the past week was 41ºF. The daytime high was 64ºF and the overnight low was 34ºF. Wind gusts were as high as 20 mph on May 7th. Precipitation was disappointing, less than two tenths of an inch. Hummingbirds have finally arrived, as have the Baltimore Orioles. Plants in flower: Ajuga (bugle), Alium (ornamental onion), Aquilegia (columbine), Arisaema triphyllum (jack-in-the-pulpit), Aurinia saxatilis (basket-of-gold), Cercis canadensis (redbud), Chelidonium majus (greater celandine), Cornus florida (native flowering dogwood), Convallaria majalis (lily of the valley), Cytisus scoparius (common broom), Deutzia, Dianthus (pinks), Euonymus alatus (burning bush), Euphorbia (spurge), Fothergillia (witches alder), Fragaria × ananassa (garden strawberry), Elaeagnus angustifolia (Russian olive), Geranium maculatum (wood geranium), Halesia carolina (Carolina silverbell), Hesperis matronalis (dame's rocket), Hyacinthoides hispanica (Spanish bluebell), Iberis (candytuft), Iris × germanica (German iris), Lamprocapnos spectabilis (bleeding heart), Leucothoe fontanesiana (highland doghobble), Lonicera (invasive bush honeysuckle), Lunaria annua (honesty, money plant), Lupinus (bluebonnet), Malus (crabapples), Narcissuss poeticus (pheasant's eye, poet's daffodil), Ornithogalum (star of Bethleham), Phlox stolonifera (creeping phlox), Polygonatum biflorum (Solomon's seal), Prunus maritima (beach plum), Rhododendron mollis, R. mucronulatum (Korean azalea), R. vaseyi (pinkshell azalea), (early azaleas, deciduous azaleas), Spiraea prunifolia  (bridal wreath), Syringa vulgaris (lilac), Trillium grandiflorum (great white trillium), Vaccinium corymbosum (highbush blueberry), Viburnum plicatum (Japanese snowbell, doublefile viburnum).
  • Pests/Problems: Leafroller defoliation on European beech. Imported willow leaf beetle skeletonization on weeping willow and American pussy willow. European pine sawflies are greater than one-half inch long and consuming last season's needles. Eastern tent caterpillar tents are numerous on native black cherries. Poison Ivy can still easily be distinguished by the newly emergent orange-red leaves. Windblown pollen is getting heavy, creating a yellow-green sheen on cars and other painted surfaces. Crabgrass is at the five to seven-leaf stage.

North Shore (Beverly)

  • General Conditions: After several weeks of cold and rainy weather with below average temperatures, the weather has been dry with clear sunny skies and variable temperatures. Day temperatures ranged from mid 50s to mid 70s with night temperatures ranged from high 30s to low 50s. The average daily temperature for this period was 54ºF with the maximum temperature of 77ºF recorded on May 7th and minimum temperature of 38ºF recorded on May 10th. Approximately 0.03 inches of rainfall were recorded at Long Hill 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. Woody plants seen in bloom during this reporting period include: beach plum (Prunus maritima), flowering dogwood (Cornus florida), redbud (Cercis canadensis), large fothergilla (Fothergilla major), dwarf fothergilla (Fothergilla gardenii), common lilac (Syringa vulgaris), Chinese lilac (Syringa x chinensis), crabapple (Malus spp.), Sargent crabapple (Malus sergentii), silverbell (Halesia carolina), Olga Mezitt rhododendron (Rhododendron ‘Olga Mezitt’), apple trees (Malus spp.) and highbush blueberry (Vaccinium corymbosum). Non-woody plants seen in bloom include: daffodil (Narcissus spp.), forget me not (Myosotis sylvatica), tulips (Tulipa spp.), bleeding heart (Dicentra spectabilis), trillium (Trillium grandiflorum), Virginia Bluebells (Mertensia virginica, barrenwort (Epimedium rubrum), Solomon’s seal (Polygonatum odoratum), vinca (Vinca minor) and money plant (Lunaria annua).
  • Iron deficiency on azalea (G.Njue) Leaf spot on mountain laurel (G. Njue) Pests/Problems: Invasive weeds garlic mustard (Alliaria petiolata) and lesser celandine (Ranunculus ficaria) are in full bloom. Other problematic weeds in bloom include dandelion (Taraxacum officinale) and violets (Viola spp.).Fungal leaf spot of mountain laurel was observed on some shrubs in the landscape. Cultural practices that promote plant vigor such as proper watering, fertilizing, properly timed hygiene tasks such as pruning, raking and removing fallen leaves in the fall will help manage this disease. Weeping cherries did not bloom this spring and they seem to be slow in leafing out, including those at Long Hill. Soil pH-induced iron deficiency symptoms were observed on some Azalea.  Ticks are very active. Be careful to protect yourself when working outdoors.

East Region (Boston)

  • General Conditions: Following last week’s cool, damp conditions, we have transitioned to consistently warm, sunny days. Daytime temperatures averaged 64ºF over the past seven days. We had an unseasonable 48ºF for a high on May 4th followed by a high of 78ºF on May 7th. We had consecutive cool nights of 42ºF and 40ºF on May 9th and 10th. We received a total of 0.25 inches of precipitation. Turf is green and growing. Plants in bloom include: Aquilegia spp. (columbine), Arisaema triphyllum (Jack-in-the-pulpit), Aronia melanocarpa (black chokecherry), Fothergilla major (large fothergilla), Polygonatum spp. (Solomon’s seal) and Phlox stolonifera (creeping phlox).
  • Pests/Problems: The white flowering garlic mustard (Arrilaria petiolata) continues to dominate roadsides and woodland edges. Japanese knotweed (Polygonum cuspidatum) red stalks are two to three feet tall. Poison Ivy (Toxicodendron radicans) is visible and detectable with its shiny, red tinged, three leafed new growth. Overall plant health continues to be a concern as many landscape plants are slow to leaf out. Many Japanese maples (Acer palmatum), flowering dogwood (Cornus florida), weeping cherry (Prunus subhirtella ‘Pendula’) and Rose of Sharon (Hybiscus syriacus) are not showing their typical vigor.

Metro West (Acton)

  • General Conditions: Weather is typical for a New England spring with varying temperatures from one day to the next, warm if not hot one day, cool the next, calm and/or windy days and nights, and then rainy, gray, and damp weather. The highest temperature recorded for this week was 79ºF on the 7th and the lowest temperature recorded was 37ºF on the 9th. The average monthly rainfall for May is 3.37” and as of the 9th, I have recorded a mere 1.01” with just over a quarter of an inch recorded this past week. The landscape is exploding with a riot of color. 
  • Pests/Problems: Eleagnus angustifolia (Russian olive), a woody invasive shrub/small tree is also flowering and can easily be detected by its silvery leaves and thorny branches. Alliaria petiolata (Garlic Mustard), one of the most invasive of all time, is just beginning to bloom and can easily be seen - because of its white flowers - growing everywhere including roadsides, woodlands, wetlands, and gardens. Other spontaneous plants seen in bloom now are Glechoma hederacea (ground ivy), Lamium purpureum (purple dead nettle) and Taraxacum officinale (dandelion). Be aware of Toxicodendron radicans (Poison Ivy). It is beginning to leaf out, so it is easy to detect its shiny red leaves of three. Black flies are active and out in force.

Central Region (Boylston)

  • General Conditions: Weather patterns this reporting period were average for the time of year. Daytime high temperatures ranged from 48ºF to 77ºF, with little recorded rainfall. Overnight low temperatures were consistently into the 40’s most nights. Lots of bright sunshine. Much is in bloom throughout the region. Lilacs (Syringa spp.) seem particularly floriferous this year. Plenty of herbaceous plants were observed in bloom, including bird’s foot violet (Viola pedata), white wakerobin (Trillium grandiflorum), and Atlantic camas (Camassia scilloides). Woody plants such as Flowering dogwood (Cornus florida), Carolina silverbell (Halesia carolina), and hawthorn (Crataegus spp.) are also nearly in full bloom.
  • Pests/Problems: Weeping cherry (Prunus × subhirtella ‘Pendula’) has barely leafed out and has not flowered, perhaps due to the extremely cold temperatures in early February. Garlic mustard (Alliaria petiolata) is in full bloom, as is autumn olive (Elaeagnus umbellata), two widespread invasive plant species in our region. Ticks, blackflies, and mosquitoes are widespread and very active.

Pioneer Valley (Amherst)

  • General Conditions: After a prolonged period of wet and cool weather, since 5/6 it’s been sunny and dry across the Pioneer Valley. Daytime temperatures are cresting in the upper 60s to upper 70s with relative humidity levels as low as 25% this reporting period. Despite the sun, low humidity and breezy conditions, soil moisture remains good. Pollen production is in full force for many trees, including oaks, and outdoor surfaces are coated. There was a frost warning in eastern Hampshire County on the morning of 5/10, but temperatures appeared to hover above freezing throughout the region. Lilac, daphne and dogwood are in full flower. Nearly every tree and shrub in the landscape is pushing new growth at an impressive rate right now. Spruce, true fir, hemlock, juniper, arborvitae, ginkgo, among other conifers are flushing bright green new growth. Spring peepers, bullfrogs, tree frogs and American toads have been heard in their various habitats. Black flies are abundant but mosquito populations seem to be relatively low right now. That will likely change quickly as the warming continues. Lawn and garden weeds, such as hairy bittercress (Cardamine), wild geranium (Geranium), henbit (Lamium), wild strawberry (Fragaria), old field cinquefoil (Potentilla), violet (Viola) and dandelion (Taraxacum) are flowering. These plants contribute to the spring color palette in untreated lawns and woodland borders. Turfgrass growth remains strong with the mild temperatures and ample soil moisture.  
  • Adult lily leaf beetles (Lilioceris lilii) feeding and mating. Photo by N. Brazee Pests/Problems: Beech leaf disease continues to be scattered in the Pioneer Valley but incidence is expected to increase with more confirmed sightings as new growth develops. Mass DCR has unveiled a new online reporting form for suspected cases of BLD, see Disease section below. Snowball aphid activity on viburnums is visible along with eriophyid mite activity on elms. Lily leaf beetles (Lilioceris lilii; see photo) were observed (and crushed). Targeting the mature adults before they can mate and lay eggs can reduce feeding pressure through the growing season. Now is the time to treat eastern hemlock for the elongate hemlock scale and hemlock wooly adelgid with dinotefuran. As new shoots and leaves develop on deciduous hardwoods, it becomes clear which stems and branches are dead. If it didn’t leaf out, prune it out. Removing dead twigs and branches from the canopy reduces inoculum of fungal cankering pathogens. Fungi such as Phomopsis, Nectria, Cytospora, and Botryosphaeria, are opportunistic and can readily attack stressed and weakened plants. Careful and close scouting is extremely important during the growing season. In many cases, this requires observation just a few inches away from the plant surface to view the early symptoms of insect feeding and disease development. Viewing from many feet away will often fail to yield early symptoms or signs that plants are infested or diseased. 

Berkshire Region (West Stockbridge)

  • General Conditions: After a cool start to the past week, which included some scattered frost on the morning of May 6th, temperatures took a jump into the low 70s on May 7th. High temperature for the three NEWA sites occurred on May 7th were: 73ºF in North Adams, 70ºF in Pittsfield, and 71ºF in Richmond. The low temperatures were: 34ºF in Pittsfield and 36ºF in Richmond on May 6th, and 35ºF in North Adams on May 9th. Another scattered frost occurred on the morning of May 10th. Rainfall levels over the week were: 0.14 inches in North Adams, 0.33 inches in Pittsfield, 0.65 inches in Richmond, and 0.23 inches at this site in West Stockbridge. Soil surfaces are quite dry with the combination of little precipitation and frequent winds. However, soils are not bone dry as they remain moist below the surface inch. Growth of plants continues at a steady pace.
  • Pests/Problems:Plant pest and disease pressures are quite low. One pest found this week was magnolia leaf scale. The spongy moths observed last week seem to have disappeared and, surprisingly, could not be found where they were first observed earlier this spring. Various soil grubs were found but not identified when digging soils. Likewise, Asian jumping worms were a common sight in these same soils. 

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 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 and pathogens of interest seen in the UMass Extension Plant Diagnostic Lab, a select few:

Beach leaf disease (BLD) symptoms should be apparent as trees leaf out this spring season. The Massachusetts DCR Forest Health group has unveiled a new online reporting form, found here: https://arcg.is/1Svrz40

Anyone who suspects they have seen an infected beech is invited to submit the location. The goal is to better track BLD as it spreads throughout Massachusetts. The nematode responsible for BLD (Litylenchus crenatae ssp. mccanii) causes damage within the buds before bud break. Therefore, leaves emerge fully symptomatic in the spring. Foliar symptoms include: (i) dark green, interveinal banding; (ii) convex cupping of the interveinal region; and (iii) stunting and distortion. Over time, when nematode populations are high, buds are killed and no new growth develops. BLD has been reported in every county in Massachusetts, but disease incidence and severity is much higher in the eastern part of the Commonwealth. With new growth developing, this is a good time for treatment with phosphites, either as a lower trunk drench or root drench around the flare. Fluopyram is a nematicide that shows promise in controlling BLD, but demand for products with this chemical is extremely high, supplies are limited, and further trials are necessary to better understand rates and timing. 

Symptoms of winter injury (pale green to brown, desiccated leaves) on a Japanese holly (Ilex crenata). Photo by N. Brazee The UMass Extension Plant Diagnostic Lab continues to receive reports and samples of trees and shrubs injured during the ‘22–’23 winter season. The deep cold the region experienced on February 3 & 4, when ambient temperatures dropped to -15ºF and wind chills approached -40ºF, is the most likely culprit in many cases. However, some injured plants may have been predisposed. Drought stress from the summer of 2022 could have hindered cold acclimation and/or the warm January could have also reduced hardiness. Ornamental and orchard cherries (Prunus spp.) were injured along with all species of holly (Ilex crenata I. glabra, I. opaca and I. pedunculosa). Symptoms on holly may appear as pale green to brown foliage that is dry and desiccated (see image). There may also be purple spots and blotches scattered across the foliage. The fungal pathogen Phyllosticta can readily colonize these injured leaves but by itself is not a serious threat to overall health. The stems may have survived and shaving the bark will often reveal healthy vascular tissue. If the stems are dead, the vascular tissue under the bark will be some shade of brown. It may be prudent to see if plants flush new growth before pruning. Boxwood were also seriouslyinjured and there are scattered reports of major injury to eastern hemlock, Japanese maple, forsythia, azalea and redbud.

Research update: Brazee N.J. and Burcham D.C. 2023. Internal decay in landscape oaks (Quercus spp.): incidence, severity, explanatory variables, and estimates of strength loss. Forests 14(5): 978.

This publication is open access and available here: https://www.mdpi.com/1999-4907/14/5/978

Scattered dieback and thinning in the canopy of a young (10-y-o) Norway spruce (Picea abies) due to Rhizosphaera needle cast (Rhizosphaera kalkhoffii) and Phomopsis stem cankering (Phomopsis sp.). The tree has been present at the site for six years and resides in full sun with drip irrigation in well-drained, loam soils. This is one of several trees planted in a berm and according to the managing arborist, was planted a bit too deep. The sample exhibited pale green needles that were prematurely shedding. Norway spruce is generally very resistant to needle cast but a combination of stem cankering and needle cast can be damaging.

Major branch dieback in the canopy of an Alaska cedar (Callitropsis nootkatensis), caused by winter injury and Phyllosticta needle blight (Phyllosticta sp.). The tree is approximately 10’ tall and was transplanted to the site four years ago. It resides in a small landscape bed in front of a residential home with full sun and well-drained soils. It has performed well in recent years without supplemental irrigation. This spring, several main branches and the terminal leader died. Needles were brown to tan in color and remained attached. Phyllosticta was abundant on the submitted needles and stems. Drought stress may also be a factor in the branch collapse. A lateral branch will need to be staked to create a new terminal leader.

Death of several Alberta spruce (Picea glauca ‘Conica’) due to drought stress, transplant shock and Botryosphaeria canker (Botryosphaeria sp.). The trees were approximately five- to seven-years-old and were transplanted last year. They were established in a woodland border garden that is mostly shaded. No supplemental irrigation was provided. In early September of last year, needles began browning and prematurely shedding. By this spring, the trees were almost entirely brown.

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

Insects and Other Arthropods

  • Deer Tick/Blacklegged Tick: Ixodes scapularis adults are active all winter and spring, as they typically are from October through May, and “quest” or search for hosts at any point when daytime temperatures are above freezing. Engorged females survive the winter and will lay 1,500+ eggs in the forest leaf litter beginning around Memorial Day (late May). For images of all deer tick life stages, along with an outline of the diseases they carry, visit: https://web.uri.edu/tickencounter/species/blacklegged-tick/ .

Anyone working in the yard and garden should be aware that there is the potential to encounter deer ticks. The deer tick or blacklegged tick can transmit Lyme disease, human babesiosis, human anaplasmosis, and other diseases. Preventative activities, such as daily tick checks, wearing appropriate clothing, and permethrin treatments for clothing (according to label instructions) can aid in reducing the risk that a tick will become attached to your body. If a tick cannot attach and feed, it will not transmit disease. For more information about personal protective measures, visit: https://web.uri.edu/tickencounter/prevention/protect-yourself/ . 

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

In the news: UMass Amherst has now been designated as the location for the New England Center of Excellence in Vector-Borne Diseases (NEWVEC). This CDC (Centers for Disease Control and Prevention) funded center will work to reduce the risk of vector-borne diseases spread by ticks, mosquitoes, and other blood-sucking insects or insect relatives in New England: https://www.umass.edu/news/article/cdc-designates-new-england-center-excellence-vector-borne-diseases-umass-amherst . For more information and to contact NEWVEC, visit: https://www.newvec.org . To contact the center for more information about their Spring 2023 Project ITCH (“Is Tick Control Helping”), visit: https://www.newvec.org/itch .

Note: Dog ticks (Dermacentor variabilis) have recently become noticeably active in parts of Berkshire and Hampshire County in 2023.

Highlighted Invasive Insects & Other Organisms Update:

  • Newly hatched spongy moth caterpillars have ballooned and settled on host plants to begin feeding on newly opened leaves in Millers Falls, MA as seen on 5/2/2023. Photo courtesy of: Nicole Keleher, MA Department of Conservation and Recreation, Forest Health Program. Spongy moth egg mass (T. Simisky) Spongy moth egg masses were seen hatching in Erving, MA on 5/2/2023. Photo courtesy of: Nicole Keleher, MA Department of Conservation and Recreation, Forest Health Program. Spongy moth egg masses were seen hatching in Great Barrington, MA on 4/18/2023. Photo courtesy of: Tom Ingersoll. Spongy Moth: Lymantria dispar egg masses are laid by the adult female moth on any flat surface, including host plants such as oak, but also fencing, buildings, steps, outdoor furniture, and more. Egg hatch typically occurs between 90-100 growing degree days (roughly the first week in May, but this varies depending upon location; in warm springs egg hatch can occur in April).

    Spongy moth egg hatch was reported on April 18, 2023, in Great Barrington, MA (Berkshire County). The tiny caterpillars can be seen on top of the egg mass from which they hatched in the photo courtesy of Tom Ingersoll. Spongy moth egg hatch has also been reported from Erving, MA and Millers Falls, MA (Franklin County) on 5/2/2023. Tiny caterpillars were observed to be dispersing and settling on host plant leaves and beginning to feed. See photos courtesy of Nicole Keleher, MA Department of Conservation and Recreation, Forest Health Program.

Spongy moth caterpillars may again be noticeable in parts of Berkshire County and abutting locations in NY and CT this year, as well as parts of Franklin County that were impacted in 2022. This is despite seeing caterpillar die-off from the spongy moth killing fungus Entomophaga maimaiga last season.

For more information from the MA Department of Conservation and Recreation, Forest Health Program, visit: https://storymaps.arcgis.com/stories/b60f63199fa14805a8b9f7c82447a25b and look under the spongy moth navigation tab.

If large numbers of egg masses are seen, plan to monitor them between 90-100 growing degree days (roughly the first week in May, but this varies) to better time egg hatch and caterpillar emergence. The MA Department of Conservation and Recreation, Forest Health Program reports that winter counts of spongy moth egg masses are higher than hoped for in parts of Berkshire County coming into the spring of 2023. This may mean that spongy moth caterpillars will again be noticeable in these areas this year, despite seeing caterpillar die-off from the spongy moth killing fungus Entomophaga maimaiga last season. For more information from the Forest Health Program, visit: https://storymaps.arcgis.com/stories/b60f63199fa14805a8b9f7c82447a25b and look under the spongy moth navigation tab.

If egg masses are plentiful near high-value specimen trees in Berkshire County in 2023, consider applying the reduced risk insecticide Bacillus thuringiensis Kurstaki (Btk) to host plant leaves before caterpillars are over ¾ inch in length. Work with a licensed pesticide applicator and arborist to plan these applications, if necessary, especially if a high-value host plant was defoliated by this insect in 2021 or 2022.

Additionally, we’ve been asked about wrapping trees to prevent spongy moth caterpillars from accessing the canopy to feed. Here is some information. If you are interested in wrapping trees or shrubs with a sticky barrier to capture older, crawling spongy moth caterpillars, there are a few things to consider. 1) This will not prevent all caterpillars from accessing the tree to feed, nor is it a guarantee that no foliage will be eaten by them on the plant to which it has been applied. 2) This will not prevent the tiniest of caterpillars (newly hatched) from ballooning on the wind into tall trees and settling to feed. For example, this could mean that caterpillars will still have some access to the leaves following their dispersal in the spring. 3) Do not apply any sticky substances directly to the tree or shrub bark to avoid risk of injury to the plant. 4) Sticky bands will need to be monitored frequently throughout the growing season, particularly in mid-to-late May and especially June, to clean and replace them.

If the bands become covered in dead caterpillars, living ones can crawl over the dead and still access the leaves of the tree. It is recommended that bands be placed on trees (and sticky material on the bands) once the caterpillars are approximately an inch in length. This may be approximately in early or mid-June. Bands should then be left up and changed frequently through July, until the caterpillars have pupated. This technique may work best with an engaged property owner that is willing and able to frequently check and help change the bands. For more information, visit: https://www.canr.msu.edu/resources/using-bands-to-protect-shade-trees-from-spongy-moth

The good news – homeowners in central and eastern Massachusetts will hopefully not have to worry too much about spongy moth this year. It may be undetectable in many central and eastern MA locations. MA DCR reports not seeing significant overwintering spongy moth egg masses in those locations. The primary area of concern includes parts of southwestern Berkshire County and areas in Franklin County that were impacted in 2022.

For more information about spongy moth, view the first episode of InsectXaminer, here: https://ag.umass.edu/landscape/education-events/insectxaminer .

Why did the common name for Lymantria dispar change recently? More information is available here: https://entsoc.org/news/press-releases/spongy-moth-approved-new-common-name-lymantria-dispar .

  • Hemlock Woolly Adelgid (T. Simisky) Hemlock Woolly Adelgid: Adelges tsugae is present on eastern and Carolina hemlock. The overwintering hemlock woolly adelgid generation (sistens) is present through mid-spring and produces the spring generation (progrediens) which will be present from early spring through mid-summer. HWA, unlike many other insects, does most of its feeding over the winter. Hemlock woolly adelgid winter mortality (due to two significant regional cold snap events) is expected to be high for 2023. HWA that were most likely to survive these extreme cold events are those on lower host tree branches, if they were insulated by snow pack at the time. Determine if HWA are alive or dead on host plants before making chemical management decisions. This can be done quickly in the field by squishing overwintered HWA in their ovisacs between your thumb and forefinger and looking for a dark brown/blackish stain (from the hemolymph, or insect blood). If staining does not occur, the insect may have died and dried up. Test at least a few insects on at least a few branches to determine if any are alive. (Much more extensive examination may involve viewing at least 200 adelgids per site/location to calculate percent winter mortality.)

Eggs may be found in woolly masses at the base of hemlock needles beginning in mid-March. Each woolly mass is created by a female who may then lay 50-300 eggs. Eggs hatch and crawlers may be found from mid-March through mid-July. Infested trees may be treated with foliar sprays in late April to early May, using Japanese quince as a phenological indicator. Systemic* applications may be made in the spring and fall, or when soil conditions are favorable for translocation to foliage. Nitrogen fertilizer applications may make hemlock woolly adelgid infestations worse.

For more information, visit: https://ag.umass.edu/landscape/fact-sheets/hemlock-woolly-adelgid .

*Note: beginning July 1, 2022 systemic insecticides known as neonicotinoids (including imidacloprid) have become state restricted use for tree and shrub uses in Massachusetts. More information is available, here:https://www.mass.gov/service-details/pesticide-newsupdates

  • Spotted Lantern Fly egg masses (T. Simisky) Spotted Lanternfly: (Lycorma delicatula, SLF) is a non-native, invasive insect that feeds on over 103 species of plants, including many trees and shrubs that are important in our landscapes. It overwinters as an egg mass, which the adult female insect lays on just about any flat surface. Pictures of egg masses can be seen here:https://massnrc.org/pests/linkeddocuments/SLFChecklistForResidents.pdf

    States south of Massachusetts (Virginia to Pennsylvania) have begun reporting spotted lanternfly egg hatch for 2023. The MA Department of Agricultural Resources expects that spotted lanternfly eggs should begin hatching in Massachusetts over the course of May. For further updates from MDAR, visit: https://massnrc.org/pests/blog/?p=3187 .

    Currently, the only established populations of spotted lanternfly in Massachusetts are in Fitchburg, Shrewsbury, Worcester, and Springfield MA. Therefore, there is no reason to be preemptively treating for this insect in other areas of Massachusetts. If you suspect you have found spotted lanternfly in additional locations, please report it immediately to MDAR here: https://massnrc.org/pests/slfreport.aspx . If you are living and working in the Fitchburg, Shrewsbury, Worcester, and Springfield, MA areas, please be vigilant and continue to report anything suspicious.

For More Information:

From UMass Extension:

*New*: Spotted Lanternfly Management Guide for Professionals:https://ag.umass.edu/landscape/fact-sheets/spotted-lanternfly-management

*Note that management may only be necessary in areas where this insect has become established in Massachusetts, and if high value host plants are at risk. Preemptive management of the spotted lanternfly is not recommended.

Fact Sheet:https://ag.umass.edu/landscape/fact-sheets/spotted-lanternfly

Check out the InsectXaminer Episode about spotted lanternfly adults and egg masses! Available here:https://ag.umass.edu/landscape/education-events/insectxaminer

From the MA Department of Agricultural Resources:

Fact Sheet and Map of Locations in MA:https://massnrc.org/pests/pestFAQsheets/spottedlanternfly.html

Spotted Lanternfly Management Guide for Homeowners in Infested Areas:https://massnrc.org/pests/linkeddocuments/SLFHomeownerMgmtGuide.pdf

  • Asian Longhorned Beetle: (Anoplophora glabripennis, ALB) Look for signs of an ALB infestation which include perfectly round exit holes (about the size of a dime), shallow oval or round scars in the bark where a female has chewed an egg site, or sawdust-like frass (excrement) on the ground nearby host trees or caught in between branches. Be advised that other, native insects may create perfectly round exit holes or sawdust-like frass, which can be confused with signs of ALB activity. 

The regulated area for Asian longhorned beetle is 110 square miles encompassing Worcester, Shrewsbury, Boylston, West Boylston, and parts of Holden and Auburn.  If you believe you have seen damage caused by this insect, such as exit holes or egg sites, on susceptible host trees like maple, please call 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 compare it to common insect look-alikes, visit: http://massnrc.org/pests/albreport.aspx or https://www.aphis.usda.gov/pests-diseases/alb/report .

This wood-boring beetle readily attacks ash (Fraxinus spp.) including white, green, and black ash and has also been found developing in white fringe tree (Chionanthus virginicus) and has been reported in cultivated olive (Olea europaea). Signs of an EAB infested tree may include D-shaped exit holes in the bark (from adult emergence), “blonding” or lighter coloration of the ash bark from woodpecker feeding (chipping away of the bark as they search for larvae beneath), and serpentine galleries visible through splits in the bark, from larval feeding beneath. It is interesting to note that woodpeckers are capable of eating 30-95% of the emerald ash borer larvae found in a single tree (Murphy et al. 2018). Unfortunately, despite high predation rates, EAB populations continue to grow. However, there is hope that biological control efforts will eventually catch up with the emerald ash borer population and preserve some of our native ash tree species for the future.

  • Winter Moth: (Operophtera brumata) data since 2017 has indicated that the winter moth population in eastern Massachusetts has been on the decline while the percent of winter moth pupae parasitized by Cyzenis albicans has increased! Dr. Joseph Elkinton’s laboratory at UMass Amherst has released this biological control agent of winter moth since 2005 and conducted the rigorous sampling required to determine where the insect has established and what its impact on the winter moth population has been at multiple sites in eastern MA.

The take-home point? Do not worry about winter moth this spring! In fact, management of this insect in landscaped settings will likely not be necessary in most locations. Blueberry growers may still, on the other hand, be interested in scouting and continuing to monitor for this insect, as only very low numbers of winter moth caterpillars might be tolerated in that system.

For blueberry and apple growers in Rhode Island, check out this winter moth update from Heather Faubert (University of Rhode Island) for April 13, 2023: https://web.uri.edu/ipm/2023/04/winter-moth-update-april-13-2023/ .

In recent years, it is worth-while to note that some areas on the Cape and other locations in eastern MA have reported noticeable native cankerworm populations in the spring, which are often confused for winter moth. Read more about cankerworms in the spring scouting list below.

  • Jumping Worms: Amynthas spp. earthworms, collectively referred to as “jumping or crazy or snake” worms, overwinter as eggs in tiny, mustard-seed sized cocoons found in the soil or other substrate (ex. compost). Immature jumping worms hatch from their eggs by approximately mid-to-late May. It may be impossible to see them at first, and it may be more likely that jumping worms are noticed when the first adults begin to appear at the end of May and in June. It is easy to misidentify jumping worms (ex. mistake European earthworms for jumping worms) if only juveniles are found. In August and September, most jumping worms have matured into the adult life stage and identification of infestations is more likely to occur at that time of year.

For More Information:

UMass Extension Fact Sheets:

Spring Scouting Suggestions & Preparation for Upcoming Tree & Shrub Insects (Native and Invasive):

  • Andromeda Lace Bug: Stephanitis takeyai 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 the 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 (starting at approximately 120 GDD’s, Base 50°F). Both nymphs and adults can be seen feeding on leaf undersides. Adults have delicate, lace-like wings and what appears to be an "inflated hood" that covers their head. Adults are approximately 1/8 of an inch long. Arrived in the US in Connecticut in 1945 from Japan (Johnson and Lyon, 1991).

    Can cause severe injury to Japanese andromeda, especially those in full sun. Mountain Andromeda (Pieris floribunda) is highly resistant to this pest. Like other lace bugs, this insect uses piercing-sucking mouthparts to drain plant fluids from the undersides of the leaves. Damage may be first noticed on the upper leaf surface, causing stippling and chlorosis (yellow or off-white coloration). Lace bug damage is distinguished from that of other insects upon inspecting the lower leaf surface for black, shiny spots, "shed" skins from the insects, and adult and nymphal lace bugs themselves.

    A first sign of potential lace bug infestation is stippling or yellow/white colored spots or chlorosis on host plant leaf surfaces. Lace bugs excrete a shiny, black, tar-like excrement that can often be found on the undersides of infested host plant leaves. Flip leaves over to inspect for this when lace bug damage is suspected.

    Mountain Andromeda (Pieris floribunda) is considered to be highly resistant to this insect and can be used as an alternative for such plantings, along with other lace bug-resistant cultivars. Consider replacing Japanese Andromeda with mountain andromeda as a way to manage for this pest. Natural enemies are usually predators, and sometimes not present in large enough numbers in landscapes to reduce lace bug populations. Structurally and (plant) species complex landscapes have been shown to reduce azalea lace bug (Stephanitis pyrioides) populations through the increase of natural enemies.

  • Azalea Lace Bug: Stephanitis pyrioides is native to Japan. The azalea lace bug deposits tiny eggs on the midveins on leaf undersides. They then cover the area where the egg was inserted with a brownish material that hardens into a protective covering. Each female may lay up to 300 eggs (University of Florida). Nymphs hatch from the eggs and pass through 5 instars. The length of time this takes depends on temperature. Between 2 and 4 generations may be completed in a single year. In Maryland, there are four generations per year. Adults are approximately 1/10 of an inch in length with lacy, cream colored, transparent wings held flat against the back of the insect. Wings also have black/brown patches. Adults of this species also possess a "hood" over their head. Nymphs are colorless upon hatch from the egg, but develop a black color as they mature and are covered in spiny protrusions. 

    Immatures and adults use piercing-sucking mouthparts to remove plant fluids from leaf tissues. This feeding leaves behind white-yellow stippling on the upper surface of host plant leaves, even though the insects themselves feed on the underside of the leaf. Plants in full sun are often particularly damaged by these insects. In heavy infestations, plants in full sun may be killed by the feeding of the azalea lace bug. 

    Begin scouting for azalea lace bugs when 120 GDD’s (Base 50°F) are reached. This species is active throughout the summer, following. 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.

    Plant azaleas in partial shade. Resistance has been reported in Rhododendron atlanticum, R. arborescens, R. canescens, R. periclymenoides, and R. prunifolium.

    Many of the natural enemies reported for this insect are predators. They are rarely abundant enough to reduce damaging populations of lace bugs, especially on plants in sunny locations. Structurally and (plant) species complex landscapes have been shown to reduce azalea lace bug (Stephanitis pyrioides) populations through the increase of natural enemies.

  • Bagworm (T. Simisky) Bagworm:Thyridopteryx ephemeraeformis is a native species of moth whose larvae construct bag-like coverings over themselves with host plant leaves and twigs. This insect overwinters in the egg stage, within the bags of deceased females from last season. Eggs may hatch and young larvae are observed feeding around mid-June, or roughly between 600-900 GDD’s. Now is the time to scout for and remove and destroy overwintered bags. In recent years, an increase in bagworm activity (particularly in urban forests) in Massachusetts has been noticed by professionals. Thus far in 2023, reports have been made from Plymouth County, MA. More information can be found here:https://ag.umass.edu/landscape/fact-sheets/bagworm
  • Black Turpentine Beetle: Dendroctonus terebrans adults may begin to be active between mid-April to mid-May. Host plants include: black pine (Pinus thunbergiana), eastern white pine (Pinus strobus), Japanese black pine (Pinus thunbergii), loblolly pine (Pinus taeda), pitch pine (Pinus rigida), red spruce (Picea rubens), Scots pine (Pinus sylvestris), and slash pine (Pinus elliottii).

    This is one of the largest native North American bark beetles. In the northern parts of its extensive range, the black turpentine beetle overwinters as an adult in the bark of its hosts. In the southern portions of its range, all life stages may be present throughout the year. Egg laying and feeding is usually kept to the basal 6 feet of the host plant. Mated pairs of adult beetles work to excavate galleries that may be 9.8 inches wide and 11.8 inches long. 100-200 eggs may be laid on one side of the gallery. Once hatched, larvae feed in groups on the inner bark. Fully grown larvae are legless, white, and almost 1/2 inch in length. Pupation occurs and adults eventually emerge from the bark to re-infest the same tree, or disperse to another susceptible host.

    Stumps and buttress roots of freshly cut trees are favored by this insect. Attacked trees may exhibit browning of needles and oozing of large masses of pitch. Masses of pitch (pitch tubes) may cover holes in the trunk and may be considerably larger than those of southern pine beetle. Pitch hardens and is first white but may turn red as it ages. Pitch is irregular in shape and up to 1.6 inches in diameter. Pitch tubes not visible when the area below soil line is attacked. Healthy trees are usually not attacked, however it has been reported on occasion. 

    Check drought-stressed or otherwise stressed trees for needles turning light green to rust color. Check the lower 6 feet, particularly the lower 18 inches of the trunk for 1.6 inch in diameter pitch tubes or small entrance holes from the adults. Reddish-brown boring dust may be found near the base of the tree as well.

  • Boxwood Leafminer: Monarthropalpus flavus partly grown fly larvae overwinter in the leaves of susceptible boxwood. Yellowish mines may be noticeable on the undersides of leaves. This insect grows rapidly in the spring, transforming into an orange-colored pupa. After pupation, adults will emerge and white colored pupal cases may hang down from the underside of leaves where adults have emerged. Adults may be observed swarming hosts between 300-650 GDD’s, or roughly the end of May through June. Most cultivars of Buxus sempervirens and B. microphylla are thought to be susceptible. If installing new boxwoods this spring, resistant cultivars such as ‘Vardar Valley’ and ‘Handsworthiensis’ are good choices at sites where this insect has been a problem. For more information, visit: https://ag.umass.edu/landscape/fact-sheets/boxwood-leafminer
  • Boxwood Mite: Eurytetranychus buxi overwinter as tiny eggs on boxwood leaves and hatch mid-spring. These mites are tiny (about the size of a period) and difficult to detect. Feeding may cause plants to appear off-color. If management is deemed necessary, the timing for treatment may be between 245-600 GDD’s.
  • Boxwood Psyllid: Psylla buxi feeding can cause cupping of susceptible boxwood leaves. Leaf symptoms/damage may remain on plants for up to two years. English boxwood may be less severely impacted by this pest. Eggs overwinter, buried in budscales, and hatch around budbreak of boxwood. Eggs may hatch around 80 GDD’s. While foliar applications may be made between 290-440 GDD’s, the damage caused by this insect is mostly aesthetic. Therefore, typically, management is not necessary. For more information, visit: https://ag.umass.edu/landscape/fact-sheets/boxwood-psyllid .
  • Cankerworms: Alsophila pometaria (fall cankerworm) and Paleacrita vernata (spring cankerworm) are often confused for winter moth (Operophtera brumata). Cankerworm populations in eastern MA, particularly on areas of Cape Cod, were confused for winter moth in 2019. Spring cankerworm adults are active in February and March, and fall cankerworm adults are active in late November into early December. During these times, both species lay eggs. These native insects most commonly utilize elm, apple, oak, linden, and beech. Eggs of both species hatch as soon as buds begin to open in the spring. Caterpillars occur in mixed populations and are often noticeable by mid-May in MA. Young larvae will feed on buds and unfolding leaves. There are two color forms (light green and dark) for caterpillars of both species. Like winter moth, they will drop to the soil to pupate. This usually occurs in June. Fall cankerworm larvae have three pairs of prolegs (one of which is small so it is sometimes referred to as ½) and spring cankerworm have two pairs. (Winter moth caterpillars also have 2 pairs of prolegs.) If populations are large and damage is noticeable on hosts, reduced risk insecticides such as Bacillus thuringiensis Kurstaki or spinosad may target larvae between approximately 148-290 GDD’s.

    For more information, visit: https://ag.umass.edu/landscape/fact-sheets/fall-cankerworm and

  • Dogwood Borer: Synanthedon scitula is a species of clearwing moth whose larvae bore not only into dogwood (Cornus), but hosts also include flowering cherry, chestnut, apple, mountain ash, hickory, pecan, willow, birch, bayberry, oak, hazel, myrtle, and others. Kousa dogwood appear to be resistant to this species. Signs include the sloughing of loose bark, brown frass, particularly near bark cracks and wounds, dead branches, and adventitious growth. The timing of adult emergence can be expected when dogwood flower petals are dropping and weigela begins to bloom. Adult moth flights continue from then until September. Emergence in some hosts (ex. apple) appears to be delayed, but this differs depending upon the location in this insect’s range. Eggs are laid singly, or in small groups, on smooth and rough bark. Female moths preferentially lay eggs near wounded bark. After hatch, larvae wander until they find a suitable entrance point into the bark. This includes wounds, scars, or branch crotches. This insect may also be found in twig galls caused by other insects or fungi. Larvae feed on phloem and cambium. Fully grown larvae are white with a light brown head and approx. ½ inch long. Pheromone traps and lures are useful for determining the timing of adult moth emergence and subsequent management.

  • Dogwood SawflyMacremphytus tarsatus has one generation per year. The larvae of the dogwood sawfly overwinter in decaying wood and occasionally compromised structural timber. An overwintering "cell" is created in this soft wood. Pupation occurs in the springtime and adults can take a lengthy time to emerge, roughly between late May and July. 100+ eggs are laid in groups on the underside of leaves. Eggs hatch and the larvae feed gregariously, initially skeletonizing leaves. As the caterpillars grow in size, they are capable of eating the entire leaf with the exception of the midvein. Larval appearance varies greatly throughout instars, so much so that one might mistake them for multiple species. Early instars are translucent and yellow, but as the caterpillars grow they develop black spots (over yellow) and become covered in a white powder-like material. Larvae and their shed skins may resemble bird droppings. Full grown larvae begin to wander in search of a suitable overwintering location. Rotting wood lying on the ground is preferred for this.

    Foliage of dogwood, especially gray dogwood (Cornus racemosa) may be impacted. Skeletonizes leaves at first, then eats all but the midvein.

  • Eastern Spruce Gall Adelgid: Adelges abietis is a pest of Norway spruce primarily, but occasionally damages other spruce species such as Colorado blue, white, and red spruce. This adelgid overwinters as a partially grown female, often referred to as a stem mother. This overwintering individual matures around bud break and lays 100-200 eggs. The eastern spruce gall adelgid may be targeted for management between 22-170 GDD’s, base 50°F (mid-April to early-May).

The eastern spruce gall adelgid may be targeted for management between 22-170 GDD’s, base 50°F (mid-April to early-May).

Egg hatch typically occurs when wild cherry leaves begin to unfold and young caterpillars may emerge by late-April through the first two weeks in May (90-190 GDD’s).

This insect is non-native, and was introduced into the United States from Europe before 1900. Galls are small, sometimes pineapple shaped/variable, but produced on the basal portion of the shoots, such that the twig extends beyond the gall. Twig dieback may occur.

  • Eastern Tent Caterpillar: Malacosoma americanum eggs overwinter on host plant twigs. Egg hatch typically occurs when wild cherry leaves begin to unfold and young caterpillars may emerge by late-April through the first two weeks in May (90-190 GDD’s). Susceptible hosts include cherry and crabapple. Other host plants whose leaves are fed upon by this native insect can include apple, ash, birch, willow, maple, oak, poplar, and witch-hazel. Where practical, prune out and remove new eastern tent caterpillar tents before they become larger as the caterpillars continue to feed. Eastern tent caterpillars are native to Massachusetts and have many associated natural enemies (parasites and predators) that help regulate populations. Unless these caterpillars are actively defoliating specimen trees in a landscaped setting, we can coexist with this particular herbivore native to our forests.
  • Elongate Hemlock Scale: Fiorinia externa is found on eastern, Carolina, and Japanese hemlock, as well as yew, spruce, and fir. The elongate hemlock scale may overwinter in various life stages, and overlap of many developmental stages at any given time can be observed throughout much of the season.

Treatments for the crawler, or mobile, stage of this insect may be made in late May through mid-June, or between 360-700 GDD’s, base 50°F.

Treatments for the crawler, or mobile, stage of this insect may be made in late May through mid-June, or between 360-700 GDD’s, base 50°F. Nitrogen fertilizer applications may make elongate hemlock scale infestations worse.

For more information, visit: https://ag.umass.edu/landscape/fact-sheets/elongate-hemlock-scale .

  • Elm Leaf Beetle: Xanthogaleruca (formerly Pyrrhaltaluteola is found on American elm (Ulmus americana; not preferred), Chinese Elm (Ulmus parvifolia; not preferred), English Elm (Ulmus procera; preferred host), Japanese Zelkova (Zelkova serrata), and Siberian Elm (Ulmus pumila; preferred host).

This species was accidentally introduced into the eastern United States early in the 1800's. Since then, it has been found throughout the USA anywhere elms are located. It also occurs in eastern Canada. The adult elm leaf beetle overwinters in protected areas, such as the loose bark of trees, but can also be a nuisance when it tries to invade homes in search of overwintering protection. Beetles will try to enter houses or sheds in the fall. 

In the spring, the adult beetles will fly back to the host plant and chew small, semi-circular holes in the leaves. The adult female can lay 600-800 yellow eggs in her life. Eggs are laid in clusters on the leaves and resemble pointy footballs. Larvae are tiny, black, and grub-like when they hatch from the egg. Young larvae will skeletonize the undersides of leaves. As they grow in size, the larvae become yellow-green with rows of black projections. Oldest larvae may appear to have two black stripes along their sides, made from the black projections. There are 3 larval instars. Mature larvae will wander down the trunk of the host tree and pupate in the open on the ground at the tree base or in cracks and crevices in the trunk or larger limbs. They spend approximately 10 or so days as a pupa, and then the adults emerge. Those adults will fly to the foliage of the same host plant or other adjacent potential hosts in the area, where they will lay eggs. In the fall, the adults will leave the host plant in search of overwintering shelter. In most locations in the USA, two generations of this insect are possible per year. In warmer locations, 3-4 generations per year are possible.

Leaves are skeletonized by the larvae. Skeletonization may cause the leaf to turn brown or whitish. Adults are capable of chewing through the leaf, often in a shothole pattern. When in very large populations, they are capable of completely defoliating plants. Populations of this insect can fluctuate from year to year, and often management is not necessary if populations are low. However, defoliation for consecutive seasons may lead to branch dieback or death of the entire tree.

  • Euonymus Scale: Unaspis euonymi is an armored scale that can be found on euonymus, holly, bittersweet, and pachysandra. This insect can cause yellow spotting on leaves, dieback, and distorted bark. For crawlers, early June timing is suggested between 533-820 GDD’s for management. (Eggs begin to hatch in early June.)
  • European Pine Sawfly: Neodiprion sertifer overwinters in the egg stage. Eggs are laid by females the previous season by cutting slits in needles using their ovipositors and depositing 6-8 eggs in each of 10-12 needles. Egg hatch occurs from late-April to mid-May and caterpillars become active roughly between 78-220 GDD, base 50°F. The primary host in MA is Mugo pine but it can be found on Scots, red, jack, and Japanese red pine. It is also found on white, Austrian, ponderosa, shortleaf, and pitch pine when planted near the aforementioned species.  This dark colored caterpillar feeds in tight groups and small numbers can be pruned or plucked out of host plants and destroyed. Spinosad products can be used whenever the caterpillars are actively feeding, usually by mid-May and when caterpillars are still small. Bacillus thuringiensis kurstaki is not effective against sawflies.
  • Fletcher Scale: Parthenolecanium fletcheri is a soft scale pest of yew, juniper, and arborvitae. Feeding scales, especially on yew, result in honeydew and sooty mold, needle yellowing, and at times, premature needle drop. There is one generation per year. Overwintered second instar nymphs can be targeted between 38-148 GDD's, base 50°F. Nymphs develop and adult females lay eggs (on average 500-600) in May that hatch by June.  Dead females conceal egg masses beneath. Crawlers migrate short distances to branches and may be concentrated on certain branches of a particular plant.
  • Forest Tent Caterpillars (T. Simisky) Forest Tent Caterpillar: Malacosoma disstria egg hatch occurs between 192-363 GDD’s, base 50°F, by mid-late May and caterpillars may be active for at least 5-6 weeks following. Susceptible hosts whose leaves are fed on by this insect include oak, birch, ash, maple, elm, poplar, and basswood. This native insect has many natural enemies, including some very effective pathogens that typically regulate populations. However, outbreaks of this insect can occur on occasion.
  • Hemlock Looper: Two species of geometrid moths in the genus Lambdina are native insects capable of defoliating eastern hemlock, balsam fir, and white spruce. Adult moths lay their eggs on the trunk and limbs of hosts in September and October, and eggs will hatch by late May or early June. (L. fiscellaria caterpillars may be active between 448-707 GDD’s.) Monitor susceptible hosts for small, inch-worm like caterpillars. Where populations are low, no management is necessary. Hemlock loopers have several effective natural enemies.
  • Holly Leafminers: Seven species of leaf miners 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 (192-298 GDD’s, base 50°F). Adult flies are known to emerge over a period of 6 or so weeks in the spring. 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. Larvae hatch from the egg and create a narrow mine that may appear brown from the upper leaf surface. Mines are broadened in the fall and a large blotch is completed in the winter. Larvae are yellow maggots and reach 1.5 mm. in length when mature. Current year’s mines are easily overlooked due to the slow feeding patterns of the larvae. Premature leaf drop may occur. Remove and destroy mined leaves before May. Phytomyza ilicis is usually only referred to as the holly leafminer, and it is a non-native species introduced from Europe and only feeds on Ilex aquifolium. (The native holly leaf miner does not develop in I. aquifolium.) The biology and damage this insect causes is similar to that of the native holly leafminer, with the exception of the fact that eggs are laid in the midvein of the leaf and young larvae tunnel in the vein until the fall. Remove and destroy mined leaves before May. Adults may be present mid-late May (246-448 GDD’s, base 50°F).
  • Honeylocust Plant Bug: Diaphnocoris chlorionis feeding results in tiny yellowish-brownish spots on leaves, leaf distortion, and in some cases, defoliation. (There are at least 7 species of plant bugs that feed on honeylocust, Gleditsia triacanthos.) There is one generation per year. Immatures and adults feed on foliage and light to moderately damaged foliage may persist throughout the growing season. Honeylocust plant bugs overwinter as eggs laid just beneath the bark surface of 2 and 3 year old twigs. Eggs hatch just after vegetative bugs of the host begin to open. Young nymphs crawl to the opening leaflets and begin feeding and the most significant damage occurs at that time, when the insect is hidden from view. Nymphs develop into adults around May-July. This insect can be targeted between 58-246 GDD’s, base 50°F.
  •  Willow Leaf Beetle (T. Simisky) Imported Willow Leaf Beetle: Plagiodera versicolora adult beetles overwinter near susceptible hosts. Adult beetles will chew holes and notches in the leaves of willow once they become available. Females lay yellow eggs in clusters on the undersides of leaves. Larvae are slug-like and bluish-green in color. They will feed in clusters and skeletonize the leaves. Most plants can tolerate the feeding from this insect, and foliage will appear brown. Repeated yearly feeding can be an issue, in which case management of the young larvae may be necessary. Take care with treatment in areas near water. 

Check out Episode 4 of InsectXaminer to see the imported willow leaf beetle in action: https://ag.umass.edu/landscape/education-events/insectxaminer

  • Japanese Cedar Longhorned Beetle: Almost on an annual basis, UMass Extension receives questions about evidence of wood boring beetle attack on eastern redcedar and similar hosts, including but not limited to: American arborvitae, Atlantic white cedar, common juniper, false arborvitae, Hinoki cypress, Japanese cedar, Leyland cypress, and others. The culprit could be the Japanese cedar longhorned beetle (Callidiellum rufipenne) or our native cedar tree borer (Semanotus ligneus). C. rufipenne is discussed here. We recommend submitting samples of the damaged plant material and any insect life stages to the UMass Plant Diagnostics Laboratory: https://ag.umass.edu/services/plant-diagnostics-laboratory/tree-shrub-diagnostics-pinewood-nematode-assay .

The Japanese cedar longhorned beetle was first detected in Washington state in 1954. This wood boring beetle is found in conifers belonging to the cypress family. Primary hosts noted for this species include arborvitae, cypress, juniper, and cedar (Chamaecyparis). Adult beetles are small, approximately ¼ to ½ inch in length with long antennae (males have antennae that are slightly longer than their bodies; females have shorter antennae). The females have reddish brown elytra (hardened wings) and the males appear darker in color (shiny blue-black) with red visible on the “shoulders” of the beetle (just behind the thorax). There is one generation per year, although in colder locations it may take 2 years to complete its life cycle. Once the females emerge from their host, they begin to lay eggs in the cracks and crevices of bark during their 20-day life span. Each female lays approximately 20 eggs (Shibata, 1994). Eggs hatch within 2 weeks and the larvae bore beneath the bark, creating tunnels or galleries as they feed in the phloem and cambium layers of the tree or shrub. Larvae are cream colored with 3 pairs of thoracic legs and grow up to approximately ¾ inch in length. As many as 10 larvae may be found in a single arborvitae branch. When the larvae are mature, they enter the xylem where they pupate, which is suspected to occur in the fall. The Japanese cedar longhorned beetle is thought to overwinter as an adult within the host plant, and emerges early the next season in the spring (Hoebeke, 1999; Humphreys and Allen, 2000; Maier and Lemmon, 2000). However, depending upon geographic location, there is discrepancy between sources regarding the overwintering life stage of this insect.

The feeding damage from the larvae of this insect causes branch dieback which may not be noticed until the following spring after initial infestation. Other signs of this insect include frass found near galleries and splits in the bark and 1/8 inch, oval exit holes. Bark may appear puckered where larval mining occurs, and frass can be seen within the mines if they are exposed by splits in the bark. Frass-packed galleries occur in the cambium and xylem. Monitor for this insect, especially in Suffolk and Nantucket Counties in Massachusetts. May also be present elsewhere in the state. Look for branch dieback on susceptible hosts in the spring. Look for bark splits, galleries, frass, and oval exit holes. With caution and the proper tools, slice open dying branches to look for galleries in the cambium and xylem and also potentially expose larvae, pupae, or adult beetles. 

Borers may be preferentially attracted to stressed plants. Take precautions to avoid plant stress, such as proper planting and site selection. Prune out and destroy infested branches prior to adult emergence in the spring. In Japan, Shibata (1994) determined that approximately 53% of pre-adult Japanese cedar longhorned beetles succumb to disease or parasitism by a suite of natural enemies. Most of the larval mortality occurs due to (as of yet) unidentified diseases; some pupal mortality occurs due to disease as well. Before pupation, larvae are also killed by two important parasitoids - Doryctes yogoi and Ischnoceros sapporensis. Two species of parasitoids from the pupal cells of Japanese cedar longhorned beetles are also known - Baeacis semanoti and Rhimphoctona spp. (Invasive Species Compendium; CABI). The full impact of natural enemies on this insect in the United States is not completely understood.

  • Lecanium Scales (Oak): Parthenolecanium quercifex overwinters as a second instar nymph on oak twigs. Females will begin feeding and mature in the spring, from mid-April to early May and eggs may be laid between late May and into June. Eggs hatch in June or early July and crawlers migrate to host plant leaves where they spend the summer and migrate as second instars back to host plant twigs in the fall. 
  • Lilac Borer: Podosesia syringae is a clearwing moth pest of lilac, privet, fringetree, and ash. (It is also known as the ash borer, not to be confused with the emerald ash borer.) Adults mimic paper wasps. Larvae are wood-boring, and signs and symptoms include branch dieback, holes, and occasionally, sawdust-like frass accumulated on bark. Larvae bore into stems, trunks, and branches, chewing an irregularly shaped entrance hole. Peak adult moth flights may occur in the northern portion of this insect’s range in June and is usually over by August 1st. Pheromone traps can be used to time adult emergence. Adult females lay flattened, oval, and tan eggs that are deposited singly or in clusters on bark crevices, ridges, and sometimes smooth bark; but usually laid in or near wounds in the bark. On average, 395 eggs are laid by each female. After hatch, larvae chew into the bark and feed laterally and then vertically in phloem tissue. Larvae overwinter in tunnels in the final instar and resume feeding in the spring. Adults emerge through a round exit hole (4-5 mm. in diameter). This insect may be targeted between 200-299 GDD’s, base 50°F.
  • Lily Leaf Beetle (T. Simisky) Lily Leaf Beetle:Lilioceris liliiadults overwinter in sheltered places. As soon as susceptible hosts such as Lilium spp. (Turk’s cap, tiger, Easter, Asiatic, and Oriental lilies) and Fritillaria spp. break through the ground, the adult lily leaf beetles are known to feed on the new foliage. (Note: daylilies are not hosts.) Adult lily leaf beetles were observed to be active in Hanson, MA on 4/14/2023. Typically, in May, mating will occur and each female will begin to lay 250-450 eggs in neat rows on the underside of the foliage. If there are only a few plants in the garden, hand picking and destroying overwintering adults can help reduce local garden-level populations at that time.  

Check out Episode 3 of InsectXaminer to see the lily leaf beetle in action:https://ag.umass.edu/landscape/education-events/insectxaminer

  • Magnolia Scale: Neolecanium cornuparvum overwinters as first instar nymphs which are elliptical, and dark slate gray in color and can usually be found on the undersides of 1 and 2 year old twigs. Nymphs may molt by late April or May and again by early June at which time the scales may be purple in color. Eventually nymphs secrete a white powdery layer of wax over their bodies.
  • Pitch mass created by the activity of the pitch mass borer seen on Norway spruce. Photo courtesy of: Jim Rassman, Service Forester, MA Department of Conservation and Recreation. Pitch Mass Borer: Synanthedon pini is a native clearwing moth whose larvae feed within various pines and spruce. Feeding by the larvae (caterpillars) of this insect causes pitch masses to form on host plants. Two or three years are required for this insect to complete its life cycle, with adult moths present during the summer. Adult pitch mass borer moths may resemble wasps. Adult males and females are blue/black from above, marked with a patch of red/orange on the underside of the abdomen, with some orange on the top of the fourth abdominal segment. Orange is also found along the sides of the abdomen. Forewings are black/blue in color and opaque with wing length of 0.47 to 0.59 inches. Adults are said to emerge, mate, and females lay eggs on their hosts some time in July. By the late summer, the larvae (immatures; caterpillars) bore into their host plant, tunneling through the trunks, often directly beneath a branch. Larvae have uniformly dark brown heads, white bodies, and prolegs with rows of 6-8 crochets on the bottom of their "feet". At the site of the borer wound, large amounts of pitch exude from the tree in a hemispherical mass above the larval tunnels. Larvae continue to feed and develop in the tree through the following year, and it is thought that caterpillars may take up to two years to mature. Masses may be 3-4 inches in diameter. Pupation occurs in a subsequent end of May through June in time for adult emergence by July and August. Pupal cells are formed within the pitch mass and lined with silk (Beuttenmüller, 1901). Pupae are 0.73 inches long and light brown in color (Kellicott, 1881).

    Adult moths are active during the summer. Following egg laying and egg hatch, the larvae tunnel under the bark to the cambium. Obvious, large globs of pitch appear on trunks. Occurs sporadically on individual trees. Host trees with active caterpillars have pitch masses that may appear coated in a white, powdery substance. Larvae may also preferentially bore into the host beneath a broken branch or scar. This insect will attack large trees, up to 30-40 feet from the ground. Healthy trees are also preferentially utilized. Overall damage to the health of the host tree is typically not extensive, and therefore chemical management of this insect is often unnecessary.

    Pitch can be removed and the single larva within destroyed. Physical/mechanical management of this insect, if it can be safely done, is a great way to manage the pitch mass borer on individual specimen trees. The act of just pulling the caterpillar from its pitch mass will kill it - much to the frustration of history's entomologists looking to study them - as soon as contact of the pitch is made with the caterpillar's body and hardens and adheres to them. Parasitism by natural enemies is reported to be relatively common. Parasitic wasps in the family Eulophidae are noted but not specified, as well as a caterpillar-eating species of fly (Engelhardt, 1946).

  • Rhododendron Borer: Synanthedon rhododendri is one of the smallest of the native clearwing moths. Rhododendrons are preferred hosts, although mountain laurel, and deciduous azaleas can be heavily infested, especially if they are planted in close proximity to rhododendrons. Injury may be first noticed in the fall (leaves lose their sheen, then become pale green, then olive, then chlorotic) and can look similar to drought stress. On branches that seem to be stunted, look at limb crotches, scars, and other irregularities for sawdust stuck on bark or on the ground beneath these areas. In late May and early June, holes may contain pupal shed skins extending halfway out. Moth emergence occurs in the late-spring, early-summer. After mating, female moths seek out suitable egg laying locations (preferring wounded areas or limb crotches). The female lays her eggs and dies. Eggs hatch and larvae tunnel into the inner bark where they feed in tunnels that become packed with reddish frass pellets. By late fall, larvae move to the sapwood where they overwinter and resume feeding by mid-March. Pupation occurs in the spring and there is one generation per year. Prune out and destroy infested branches before late May/June. Monitor for adults in mid-May (192-298 GDD’s, base 50°F). 
  • Snowball Aphid: Neoceruraphis viburnicola eggs overwinter on viburnum twigs and buds. Eggs hatch and this aphid becomes active on certain species of viburnum roughly between 148-298 GDD’s or around redbud bloom. This insect is particularly noticeable on V. opulus, V. prunifolium, and V. acerifolia. Stem mothers, appearing blueish-white, can be found in curled up and distorted foliage. Damage caused by this insect pest is mostly aesthetic.
  • Spruce Bud Scale: Physokermes piceae is a pest of Alberta and Norway spruce, among others. Immatures overwinter on the undersides of spruce needles, dormant until late March. Immatures overwinter on the undersides of spruce needles, dormant until late March. By April, females may move to twigs to complete the rest of their development. Mature scales are reddish brown, globular, 3 mm. in diameter, and found in clusters of 3-8 at the base of new twig growth. They closely resemble buds and are often overlooked. Crawlers are present around June.
  • Spruce Spider Mite: Oligonychus ununguisis a cool-season mite that becomes active in the spring from tiny eggs that have overwintered on host plants. Hosts include spruce, arborvitae, juniper, hemlock, pine, Douglas-fir, and occasionally other conifers. This particular species becomes active in the spring and can feed, develop, and reproduce through roughly June. When hot, dry summer conditions begin, this spider mite will enter a summer-time dormant period (aestivation) until cooler temperatures return in the fall. This particular mite may prefer older needles to newer ones for food. Magnification is required to view spruce spider mite eggs. Tapping host plant branches over white paper may be a useful tool when scouting for spider mite presence. (View with a hand lens.) Spider mite damage may appear on host plant needles as yellow stippling and occasionally fine silk webbing is visible.
  • Taxus Mealybug: Dysmicoccus wistariae will produce honeydew and lead to sooty mold growth, yellowing of needles, and sparsely foliated plants. Eventual dieback may be possible. This species is commonly associated with taxus in New England, but can be occasionally found on dogwood, rhododendron, Prunus spp., maple, andromeda, and crabapple. These mealybugs are found on stems and branches and particularly like to congregate at branch crotches. Taxus mealybug feeds in the inner bark tissue of the trunk and branches. Adult females are present from June to August and give birth to living young in the summer. Immatures overwinter. A single generation may occur per year in New England, but areas to the south can have multiple generations of this insect. Management may be targeted between 246-618 GDD’s, base 50°F. Horticultural oil and neem oil may be used.
  • Viburnum Leaf Beetle: Pyrrhalta viburni is a beetle in the family Chrysomelidae that is native to Europe, but was found in Massachusetts in 2004. By 2008, viburnum leaf beetle was considered to be present in all of Massachusetts. Larvae are present and feeding on plants from approximately late April to early May until they pupate some time in June. Adult beetles emerge from pupation by approximately mid-July and will also feed on host plant leaves, mate, and lay eggs at the ends of host plant twigs where they will overwinter. This beetle feeds exclusively on many different species of viburnum, which includes, but is not limited to, susceptible plants such as V. dentatum, V. nudum, V. opulus, V. propinquum, and V. rafinesquianum. Some viburnum have been observed to have varying levels of resistance to this insect, including but not limited to V. bodnantense, V. carlesii, V. davidii, V. plicatum, V. rhytidophyllum, V. setigerum, and V. sieboldii. More information about viburnum leaf beetle may be found athttp://www.hort.cornell.edu/vlb/ and here: https://ag.umass.edu/landscape/fact-sheets/viburnum-leaf-beetle .
  • White Spotted Pine Sawyer (WSPS): Monochamus scutellatus adults can emerge in late May throughout July, depending on local temperatures. This is a native insect in Massachusetts and is usually not a pest. Larvae develop in weakened or recently dead conifers, particularly eastern white pine (Pinus strobus). However, the white spotted pine sawyer looks very similar to the invasive Asian Longhorned Beetle, Anoplophora glabripennis, ALB. ALB adults do not emerge in Massachusetts until July and August. Beginning in July, look for the key difference between WSPS and ALB adults, which is a white spot in the top center of the wing covers (the scutellum) on the back of the beetle. White spotted pine sawyer will have this white spot, whereas Asian longhorned beetle will not. Both insects can have other white spots on the rest of their wing covers; however, the difference in the color of the scutellum is a key characteristic. See the Asian longhorned beetle entry above for more information about that non-native insect.
  • Woolly Apple Aphid (T. Simisky) Woolly Apple Aphid: Eriosoma lanigerum may be found on apple, crabapple, hawthorn, mountain ash, Pyracantha, and elm hosts. The primary (winter) host is elm, on which aphids infest emerging spring leaves, causing leaves to curl or close into stunted, rosette-like clusters found at twig tips. On apple and crabapple, this species of aphid colonizes roots, trunks, and branches in the summer and is commonly found near previous wounds or callous tissue. On roots, the aphids cause swelled areas which can girdle and kill roots. The aphids, when found in above ground plant parts such as elm leaves, are covered with white wax. Eggs are the overwintering stage on elm, which hatch in the spring in time for the nymphs to infest new elm foliage. Following a few generations on elm, the aphids will develop into a winged form, which will disperse and seek out apple and crabapple. Multiple generations will occur on these alternate hosts in the summer and by the fall, a winged form will return to elm and mated females will lay eggs near elm buds. These aphids are a favorite snack for insect predators such as the multicolored Asian lady beetle, Harmonia axyridis.
  • Woolly Elm Aphid (T. Simisky) Woolly Elm Aphid: Eriosoma americanum females lay a single egg in the cracks and crevices of elm bark, where the egg overwinters. Eggs hatch on elm in the spring as leaves are unfolding. Aphids may be active from 121-246 GDD’s, base 50°F on elm. Aphids may be active from 121-246 GDD’s, base 50°F on elm. A young, wingless female hatched from the egg feeds on the underside of leaf tissue. This female aphid matures and gives birth to 200 young, all females, without mating. These aphids feed, and the elm leaf curls around them and protects them. By the end of June, winged migrants mature and find serviceberry hosts. Another set of females is produced. These new females crawl to and begin feeding on the roots of serviceberry. Multiple generations occur on the roots of serviceberry through the summer.

Concerned that you may have found an invasive insect or suspicious damage caused by one? Need to report a pest sighting? If so, please visit the Massachusetts Introduced Pests Outreach Project:http://massnrc.org/pests/pestreports.htm .

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


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