Landscape Message: April 9, 2021

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.

The Landscape Message will be updated twice more in April. The next message will be posted on April 23. To receive immediate notification when the next Landscape Message update is posted, be sure to join our e-mail list 

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

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Scouting Information by Region

Environmental Data

The following data was collected on or about April 7, 2021. Total accumulated growing degree days (GDD) represent the heating units above a 50° F baseline temperature collected via regional NEWA stations for the 2021 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 (2-Week Gain)	Time/Date of Readings
	2-Week Gain	2020 Total	Sun	Shade
CAPE	14.5	20.5	48	43	0.90	12:00 PM 4/7
SOUTHEAST	26	30	58	47	0.20	3:00 PM 4/7
NORTH SHORE	23	32.5	45	45	0.71	10:00 AM, 4/7
EAST	29	37	56	50	0.73	4:00 PM 4/7
METRO	30.5	33.5	44	42	0.48	9:00 AM 4/7
CENTRAL	30	35	45	45	0.43	7:00 AM 4/7
PIONEER VALLEY	30	35.5	49	46	0.00	12:00 PM 4/7
BERKSHIRES	18	18	46	38	0.18	8:30 AM 4/7
AVERAGE	25	30	49	44.5	0.45	_

See MA drought status as of April 6 here: https://droughtmonitor.unl.edu/CurrentMap/StateDroughtMonitor.aspx?MA

Phenology

Indicator Plants - Stages of Flowering (BEGIN, BEGIN/FULL, FULL, FULL/END, END)
PLANT NAME (Botanic/ Common)	CAPE	S.E.	N.S.	EAST	METRO W.	CENT.	P.V.	BERK.
Magnolia stellata (Star Magnolia)	Begin	Full	Full	Begin/Full	Begin	Begin	Begin/Full	*
Forsythia x intermedia (border Forsythia)	Begin	Begin/Full	Begin/Full	Begin/Full	Begin	Begin	Begin/Full	Begin
Pieris japonica (Japanese Pieris)	Begin/Full	Full	Full	Begin/Full	Begin/Full	Begin	Begin	Begin
Cornus mas (Cornelian cherry dogwood)	Full	Full	Full	Full	Full	Full	Full	Begin
Acer rubrum (red maple)	Begin/Full	Full	Full	Full/End	Full/End	Full	Full	Begin/Full
Acer saccharinum (silver maple)	Full/End	Full	Full/End	Full/End	Full/End	Full/End	Full/End	Begin/Full
Hamamelis x intermedia (witchhazel hybrids)	End	Full	Full/End	Full/End	Full/End	End	Full/End	Full
* = no activity to report/information not available

Regional Notes

Cape Cod Region (Barnstable)

General Conditions: The period from 3/17 thru 4/7 had a high of 66˚F on March 25 and a low of 24 ˚F on March 20. Overall, the period has been mild with mostly sunny days. The last below freezing temperature was on April 4 reaching 27˚F. Typically, the area sees its last freeze date sometime in mid – late April. The sunny days have led to good outdoor working conditions. There were 4 precipitation events during the period providing 3.11 inches of rain since March 17. Even with that precipitation soils still seem fairly dry. Peepers can be heard on mild evenings. Plants that can be seen in bloom include hellebores, daffodils, some early Iris (Iris reticulata), crocus, the beginning of some hyacinths and Pulmonaria. Some willows are in full bloom, lilac buds are getting large and apple trees are in green tip.

Pests/Problems: This is the time of year that many people start thinking about the pests that attack our forest and landscape trees. Gypsy moth and winter moth are not expected to cause significant defoliation locally. Holes in leaves from winter moth can still be expected but holes don’t reduce plant health like defoliation and don’t require management. In the last couple of years, small pockets of fall cankerworm defoliation have occurred, in many cases mistaken as winter moth damage: it’s something to keep an eye out for.

The lecanium scale population which has been widespread on the Cape for a couple years can be found at varying levels. I have seen areas recently in which populations have been greatly reduced primarily by entomopathogenic fungi but there are also locations still with extremely high populations. Now is the time to scout for the tiny lecanium scales by looking for the scale on the previous season’s growth, white oak seems to be a preferred host so the best tree to use for scouting. When scouting for lecanium scale in late winter/early spring, scout the previous season’s growth on white oak. Healthy scales are tiny and reddish brown. Populations of this size are likely to require management on high value trees.

The extreme drought from last year can be seen in many landscapes evergreens in particular are showing the worst symptoms. Rhododendron in unirrigated landscapes have a tremendous amount of dieback. Arborvitae also has a lot of damage both drought and winter injury related to drought. Secondary pests are likely to be seen this year as secondary pest often attack weakened and stressed trees. Secondary pests often include organisms like bark beetles and borers as well as fungi like Armillaria. Pest or pest damage seen during the period include injury to white pine. A large mixed-aged stand of white pine was found in various stages of decline. Trees were likely stressed by drought and some had been attacked by black turpentine beetle. Other pests found included the bark beetle Pityogenes hopkinsi and the Cerambycid beetle Rhagium inquisitor which appeared to be finishing the trees off. Damage from black turpentine beetle seemed anecdotally higher last year and the expectation would be to see more pressure from this pest again this year. The disease called tulip fire (Botrytis tulipae) was seen on a large planting of tulips. A large barnacle scale was found on inkberry (Ilex glabra).

It is a good time of year to work on invasive shrub removal when soils are moist and small shrubs can often be pulled. Many of the invasive shrubs start to emerge before many of our native shrubs like Viburnum. Multiflora rose and the invasive bush honeysuckles are easily spotted at this time of year due to the early growth. The invasive fig buttercup (Ficaria verna) can be seen in bloom. The following weeds are in bloom: the dreaded hairy bittercress, whitlow grass, chickweed, speedwell, even a dandelion flower can be spotted here and there. Lawns are starting to green up. Unirrigated lawns are especially likely to require significant care to ensure that weeds do not get established in weak areas or areas that are unable to recover from last year’s drought. It is hard to imagine that rabbit populations could get any larger than last year but reports of damage and sightings already seem to be high. Food resources for squirrels are often at a seasonal low in late winter and early spring and several reports of squirrels feeding on flower buds of ornamental trees and shrubs have been received. Don’t forget to protect yourself from ticks.

Southeast Region (Dighton)

General Conditions: Spring has shifted into a higher gear in the past few days. Buds are swelling and shedding covers. Lawns are greening up, hopefully. Wood frogs, spring peepers, and other amphibian’s calls are strong and loud in the evening. The insects are waking up: cabbage moth, honey bees, blow flies, carpenter ants and spiders, to mention a few, are all active. Worm castings are evident on lawns. Opuntia cactuses have awoken from their wrinkly, winter worn-out shoe leather turgor and now stand upright, waving sideways “hello”. The year-round songbirds are slightly more settled, spending less time squabbling with the neighbor's spouse and more on foraging for the future family. The alewife migration is in full swing, flashing silvery sides in the sunlit eddies along streams and brooks like at Oliver Mill Park on the Nemasket River. Flights of cormorants move like furtive shadows on a mission along the Taunton riverbanks close to the water. Osprey can be seen over Bristol County Aggie sailing their catch like a jib in the wind. The early trees have light halos of red, yellow and green flowers, catkins and buds as they line the horizon or stand sentinel in fields. Turkey vultures are back patrolling the highways for winter's grisly bounty. Local news reports that black vultures, a typically more southern species, have taken up residence in an attic apartment in New Bedford. I'm not sure if this is a sign of climate change but they seem to have given up on migrating, choosing to “rent” instead. (https://turnto10.com/news/local/rare-black-vulture-sighted-at-an-abandon...). Norway Maple cotyledons are emerging everywhere from gutter leaf litter piles like dragon's teeth. Fall sown annual poppy seedings are at second and third true leaf. Common violets have their first set of leaves. Some plants observed in bloom include: Acer rubrum (swamp red maple), A. saccharinum (silver maple), Cardamine hirsuta (hairy bittercress), Cornus mas (Cornelian cherry dogwood), Forsythia spp., Hamamelis x intermedia (witchhazel), Hyacinthus orientalis (Dutch hyacinth) Leucojum aestivum (summer snowflake), Lindera benzoin (spicebush), Magnolia stellata "Centennial" (star Magnolia), Muscari amenicanum (grape hyacinth), Narcissus spp.(jonquil, daffodil), Pieris japonica (Japanese andromeda), Pulmonaria spp.(lungwort), Salix spp.(willows, sallows), Scilla forbesii (Forbes’ glory-of-the-snow), S. siberica (Siberian or wood squill), Stellaria media (chickweed), Tulipa spp. (Tulip), Symplocarpus foetidus (skunk cabbage) and Ulmus americana (American elm).

Pests/Problems: Deer tick adults are active, and anecdotally in our area, crews have run into what may be the overwintering, engorged larvae or early emerging nymphs that usually are active in May and the size of a poppy seed. What we believe to be four or five immature ticks were found on each crew member. This emphasizes the need to protect yourselves from these disease-carrying organisms! Our mild winter has many consequences, not all beneficial. I am already getting calls about biting flies, presumed to be mosquitoes but are more likely black flies. There's been quite a lot of coyote activity in my area this season. According to recent reports from the National Park Service, 20% of the suburban coyote diet is house cats. This predation is said to be a significant control of feral cat populations.

North Shore (Beverly)

General Conditions: The weather since the last reporting period has been variable. The average daily temperature during this period was 47℉. The minimum temperature was 27℉ recorded on March 20th and the maximum temperature was 72℉ recorded on March 26. There has been minimal precipitation recorded in the area; only 0.71 inches have been recorded at Long Hill since the beginning of April. The weather has been dry for most days during this period. Woody plants observed in bloom include cornelian cherry dogwood (Cornus mas), goat willow (Salix caprea), anise Magnolia (Magnolia salicifolia), Merrill Magnolia (Magnolia x loebneri), winter honeysuckle (Lonicera x purpusii), February Daphne (Daphne mezereum), white Forsythia (Abeliophyllum distichum), Winterthur winterhazel (Corylopsis ‘Winterthur’) fragrant Viburnum (Viburnum farreri) and red maple (Acer rubrum). Early spring flowering bulbs seen in bloom include: hellebores (Helleborus orientalis), Siberian squill (Scilla siberica) and Puschkinia (Puschkinia libanotica), glory of the snow (Chionodoxa), snowdrops (Galanthus spp.), daffodil (Narcissus spp.) and early, white woodland ‘Tommy’ Crocus (Crocus tommasinianus).

Pests/Problems: Due to the dry conditions, fire danger warnings are posted in many communities. Yellow buttercup weed (Ficaria verna, formerly Ranunculus ficaria L.), commonly known as lesser celandine or pilewort, has started blooming on lawns. As temperatures start to rise, tick activity will also rise. Take precautions when working outdoors. Apply repellents such as DEET before you go out into the woods.

East Region (Boston)

General Conditions: March ended with above average daytime temperatures in the mid-sixties and two beneficial rain events. April has begun cooler with several overnight lows reaching 30˚F with minimal precipitation. We did receive 0.73” precipitation on April 1st for a total of only 1.42” since the last reporting period on March 17. The landscape is beginning to show some color with Crocus spp., daffodils and Forsythia spp. commonly seen in bloom. Early Magnolias are in various stages of bloom depending on their location. The less commonly seen Abeliophyllum distichum (white Forsythia), Corylopsis spp. (Winterhazel), and Helleborus niger (Christmas rose) are also in flower. Gaining popularity as a street tree, the early blooming Prunus ‘Okame’s (Taiwan cherry) pink flowers are unmistakable throughout the city.

Pests/Problems: Dry soils are an ongoing concern. We have had several 7-10 days stretches this year without significant rainfall. Winterburn is visible on boxwood, Kalmia spp., Rhododendron spp. and other unprotected evergreens. Ticks are prevalent in meadows and woodlands. Maple, poplar and juniper are flowering and adding significant amounts of pollen to the dry air.

Metro West (Acton)

General Conditions: Spring arrived just three weeks ago and brought with it weather that has been pretty typical for spring including warm and cool temperatures, a snow flurry, blustery days, and rain. High temperatures of 70˚F and 72˚F were recorded on the 25^th and 26^th, respectively, and a low temperature of 19˚F was recorded on the 20^th. Wind gusts upwards of 39 to 37 mph were recorded on the 28^th and 26^th respectively. Average rainfall for the month of March is 4.83” and the total recorded for the month was 1.7”. The average monthly rainfall for the month of April is 4.16” and as of the 6^th, 0.48”of rain has been recorded so far. In bloom at this time are: Acer rubrum (red maple), Adonis amurensis (Adonis), Cornus mas (cornelian cherry dogwood), C. officinalis (Japanese cornelian cherry dogwood), Crocus spp., Forsythia spp., Hamamelis × intermedia cultivars (witch hazel), Helleborus niger (Christmas rose), Magnolia stellata (star Magnolia) Petasites japonicus (Japanese butterbur), Pieris japonica (Japanese andromeda), and Symplocarpus foetidus (skunk cabbage). Buds are swelling on a number of woody plants including Lindera benzoin (spicebush), Syringa sp. (lilac) and Viburnum spp.

Pests/Problems: Let’s hope for many more long and soaking April showers. Precipitation is at a low and I am anxious to hear what the Drought Management Task Force will declare for this area in the coming weeks with the lack of precipitation. Ticks are active. Draba verna (spring whitlow grass), Lamium purpureum (purple deadnettle), Taraxacum officinale (dandelion) have all been seen in bloom.

Central Region (Boylston)

General Conditions: What a burst of color the last few weeks brought across the region! Early spring bulbs like daffodils (Narcissus), Siberian squill (Scilla siberica), Lucile’s glory-of-the-snow (Scilla luciliae), and winter aconite (Eranthis hyemalis) are in full bloom. Many of our dominant canopy trees are flowering and sending out their first leaves of the season. Despite all the early seasonal color and warm daytime temperatures, it’s not quite time to start moving houseplants outdoors. Overnight temperatures have frequently dipped below freezing. Now is a great time of year to prune dead and broken branches from trees and shrubs. As buds start to open, it’s very easy to see which branches did not survive winter.

Pests/Problems: Although the US Drought Monitor map has not been updated as of this report, April is starting out abnormally dry. Less than ½-inch of precipitation is not enough at this crucial time of year. Undisturbed soils are still moist thanks to cooler temperatures, but recently worked soils are noticeably dry. Ticks are quite active, as are mosquitoes.

Pioneer Valley Region (Amherst)

General Conditions: Spring continues to progress in the Pioneer Valley as the days get longer and more plants begin flowering. Across most of southern New England, March was warmer than average, according to the NRCC. The above-average temperatures have helped advance flowering, new growth and the breaking of winter dormancy. After a mostly uninterrupted sunny stretch for the first three weeks of March, the final week of the month saw several scattered showers and more consistent cloud cover. The valley received measurable precipitation on 3/28, 3/29 and 3/31, totaling ~1.5” overall. Since then, dry and sunny conditions have resumed. Strong spring winds were abundant over this last reporting period, with wind gusts of 46 mph (3/29) and 38 mph (4/5) recorded at Barnes Airport in Westfield. Nighttime temperatures bottomed out in the low 20s on 4/3 and 4/4, but since then have hovered in the upper 30s. Hopefully, we don’t return to freeze temperatures at night but it’s far too early in April to rule that out. Last year, we had freezing temperatures in late April and frost in early May. Across the landscape, juniper, arborvitae, false-cypress, larch, euonymus and honeysuckle are pushing new growth right now. Buds on many different trees, including oaks, continue to swell. Turf grasses are greening in both sun and shade. Soil temperatures continue to increase and new root growth can typically take place ≥50°F.

Pests/Problems: The sunny days, spring winds and low humidity are already drying out the upper soil horizon in full sun locations. Recently transplanted conifers should be checked regularly to ensure adequate soil moisture is available. Their dense canopies can sometimes shield the root ball from being wetted after rain. Scout for spruce spider mite (Oligonychus ununguis) activity, especially on spruce and arborvitae. This cool season mite is active and feeding at this time can go unnoticed. Symptoms of building infestations may not become apparent until later in May or June. Horticultural oil and insecticidal soaps can be used at this time, along with a range of miticides that are labeled for use. Broad-spectrum insecticides should be avoided, as they also target beneficial predators of spider mites. Winter burn is more visible now that temperatures are warming and more time has passed since the deep cold of February. Injury has been observed on hemlock, false-cypress and rhododendron. Rabbits are active in the landscape, eating spring bulbs and clipping small, low-growing shoots. Localized damage on small diameter trees is often the result of rabbits as well. Certain cankering pathogens may be active now, expanding into healthy tissues before the host tree breaks dormancy and responds with an active defense response.

Berkshire Region (Great Barrington)

General Conditions: Yo-yo weather continued its pattern over the past 2 weeks with record high temperatures on March 25 and 26 followed a week later by the April Fool’s Day snow, albeit a light snow which amounted to about ½ inch in most locales within the County. Nevertheless, total precipitation for the year as of April 7 is almost 4 inches below normal for the year. Soil moisture levels were high at the beginning of the week but with sun and wind they have dried enough to be workable - a good time for planting trees and shrubs. Grass is greening rapidly but has not yet shown much growth. That will change quickly with rising temperatures.

Pests/Problems: The two most serious issues observed this week are the high population of black-legged ticks and the damage to woody plant stems due to gnawing by rodents. The ticks which are active now are those in the adult stage. They are not only attaching themselves to landscape workers but to anyone spending time outdoors. Household pets are also frequent hosts and should be routinely checked for ticks if they have been outdoors. Perhaps due to a prolonged stretch of snow cover this winter, there has been considerable damage to the stems of shrubs and the bark of young trees. Because the damage, stripped or gnawed bark, appears near the base of the plants, the most likely culprits are meadow voles. Other evidence of the presence of meadow voles is the appearance of runways in lawns. Snow mold is also apparent in some lawns, as indicated by fluffy light-colored patches. Several very high wind events over the past few months brought down several trees throughout the county but more often broke tree limbs.It’d be wise to examine trees around homes and other structures for dangling tree branches. Boxwood leaf miner larvae are active and feeding between the epidermal layers of boxwood. Pruning the larva-laden boxwood foliage this month will reduce the number of adults hatching out in May.

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 Tower Hill Botanic Garden, 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 (https://ag.umass.edu/services/plant-diagnostics-laboratory):

• Severe case of edema, caused by overwatering, on a Japanese yew (Taxus cuspidata 'Capitata'). Hedge of 20 shrubs that were planted in 2010 and are 3–4’ tall. Only one of the plants exhibited symptoms of stress and it was suspected to be a needle blight by the managing landscaper. Upon closer inspection, the needles were yellowing and had numerous raised, corky blisters on the upper and lower surface of the needles. There was no evidence of disease or insect attack. The plants reside in shade and receive both overhead and drip irrigation. Yews can be very sensitive to overwatering once they are established and exhibit a high level of drought resistance in most settings.
• Needle browning and branch dieback of an eastern hemlock (Tsuga canadensis) caused by winter injury and the elongate hemlock scale (Fiorinia externa). The tree is approximately 30-years-old and resides in full sun. Symptoms of canopy dieback were not apparent in previous years and developed this spring season. A well-established scale infestation was noted but needle browning and premature shedding caused by winter injury was also apparent. Horticultural oil was applied from 2017–2019, which can reduce the thickness of the needle cuticle. Drought stress from 2020 may have also inhibited the tree’s ability to naturally acclimate to cold temperatures. The combination of cuticle thinning due to oil application, drought and scale feeding likely predisposed the tree to winter burn.
• Dieback of Norway spruce (Picea abies) caused by the Norway spruce gall midge (Piceacecis abietiperda), spruce spider mite (Oligonychus ununguis) and eastern spruce gall adelgid (Adelges abietis). Several large trees, approximately 70-years-old, in various stages of canopy decline. The trees reside in a landscaped woodland with full sun and well-drained, loam soils. While populations appear to have declined in recent years, the Norway spruce gall midge can still be locally abundant and some trees harbor significant infestations. This tiny, fly-like insect causes distorted and blighted stems as larval chambers develop at the base of new shoots. Adult spider mites were visible when the sample arrived in late March, illustrating their cool season preference.
• Uprooting of a large eastern white pine (Pinus strobus) due to Armillaria root rot and strong winds. The tree was approximately 70-years-old and developed in a grove of trees on the UMass campus near the Chancellor’s House. Strong winds in early March caused the tree to uproot and when it fell, it crushed a nearby shed. Inspection of the buttress roots where the failure occurred revealed a white, spongy decay of the root tissue. Closer examination revealed mycelial fans produced by the native root decay pathogen, Armillaria. Mature white pines are often resistant to Armillaria root rot but no tree is immune to this dynamic fungal pathogen.
• Winter injury on cherry laurel (Prunus laurocerasus). Several plants, approximately ten-years-old, were planted last summer. The setting is described as full sun with poorly drained soils and exposure to strong winds. One plant exhibited a red-brown discoloration to the foliage that is typical with winter injury on evergreen plants. No insects or disease-causing pathogens were detected.

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

Insects

Insects and Other Arthropods

• Deer Tick/Blacklegged Tick: Check out the archived FREE TickTalk with TickReport webinars available here: https://ag.umass.edu/landscape/education-events/webinars.

*Ixodes scapularis adults have been active all winter, 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: http://www.tickencounter.org/tick_identification/deer_tick .

Anyone working in the yard and garden on springtime cleanup and planting 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: http://www.tickencounter.org/prevention/protect_yourself .

The UMass Laboratory of Medical Zoology is currently unable to accept samples for tick testing at this time. The Massachusetts Department of Public Health provides a list of potential tick identification and testing alternatives here: https://www.mass.gov/service-details/tick-identification-and-testing-services

*Note that deer ticks (Ixodes scapularis) are not the only disease-causing tick species found in Massachusetts. The American dog tick (Dermacentor variabilis) and the lone star tick (Amblyomma americanum) are also found throughout MA. Each can carry their own complement of diseases, including others not mentioned above. Anyone working or playing in tick habitats (wood-line areas, forested areas, and landscaped areas with ground cover) should check themselves regularly for ticks while practicing preventative measures.

Woody ornamental insect and non-insect arthropod pests to consider, a selected few:

Invasive Insects & Other Organisms Update: 

• Spotted Lanternfly: (Lycorma delicatula, SLF) is not known to be established in Massachusetts landscapes at this time. However, due to the great ability of this insect to hitchhike using human-aided movement, it is important that we remain vigilant in Massachusetts and report any suspicious findings. Spotted lanternfly reports can be sent here: https://massnrc.org/pests/slfreport.aspx .

The Massachusetts Department of Agricultural Resources has recently released spotted lanternfly Best Management Practices for Nurseries and Landscapers: https://massnrc.org/pests/linkeddocuments/MANurseryBMPs.pdf

And Best Management Practices for Moving Companies and the Moving Industry: https://massnrc.org/pests/linkeddocuments/SLFChecklistMovingIndustryMA.pdf

Now is a great time to provide copies of these BMP’s to employees, customers, family, and friends! The more eyes we have out there looking for spotted lanternfly, the better. Spotted lanternfly egg masses overwinter, and are laid by these insects on just about any flat surface. Use the above BMP’s as a guide to help you inspect certain items coming from CT, DE, MD, NC, NJ, NY, OH, PA, WV, and VA.

UMass Extension is teaming up with UMass Amherst’s Department of Environmental Conservation, the USDA APHIS, and the Massachusetts Department of Agricultural Resources to monitor for the spotted lanternfly in Massachusetts. A team including members of UMass Extension’s Landscape, Nursery, and Urban Forestry Program, Extension’s Fruit Program, Stockbridge School of Agriculture, and the Department of Environmental Conservation at UMass, Amherst are undertaking a nine-month integrated research and extension project to develop effective tools to detect the spotted lanternfly.

The researchers associated with this project (Dr. Joseph Elkinton, Dr. Jeremy Andersen and Dr. Jaime Pinero) will be working with Dr. Miriam Cooperband of the USDA APHIS lab on Cape Cod to identify and evaluate airborne attractants that can improve the ability to detect SLF in traps. Dr. Cooperband has identified several attractant lures released from host plants of SLF. She is currently working on pheromones produced by SLF that may be much more attractive. The UMass team will help her conduct field tests of these new lures, while also assisting the Massachusetts Department of Agricultural Resources (MDAR) in monitoring for SLF in Massachusetts. UMass Extension Entomologist, Tawny Simisky, will periodically report on progress made during the course of this project. For more information, please visit: https://ag.umass.edu/cafe/news/looking-for-spotted-lanternfly-recent-invasive-arrival

This insect is a member of the Order Hemiptera (true bugs, cicadas, hoppers, aphids, and others) and the Family Fulgoridae, also known as planthoppers. The spotted lanternfly is a non-native species first detected in the United States in Berks County, Pennsylvania and confirmed on September 22, 2014.

For a map of known, established populations of SLF as well as detections outside of these areas where individual finds of spotted lanternfly have occurred (but no infestations are present), visit: https://nysipm.cornell.edu/environment/invasive-species-exotic-pests/spotted-lanternfly/

The spotted lanternfly is considered native to China, India, and Vietnam. It has been introduced as a non-native insect to South Korea and Japan, prior to its detection in the United States. In South Korea, it is considered invasive and a pest of grapes and peaches. The spotted lanternfly has been reported feeding on over 103 species of plants, according to new research (Barringer and Ciafré, 2020) and when including not only plants on which the insect feeds, but those that it will lay egg masses on, this number rises to 172. This includes, but is not limited to, the following: tree of heaven (Ailanthus altissima) (preferred host), apple (Malus spp.), plum, cherry, peach, apricot (Prunus spp.), grape (Vitis spp.), pine (Pinus spp.), pignut hickory (Carya glabra), sassafras (Sassafras albidum), serviceberry (Amelanchier spp.), slippery elm (Ulmus rubra), tulip poplar (Liriodendron tulipifera), white ash (Fraxinus americana), willow (Salix spp.), American beech (Fagus grandifolia), American linden (Tilia americana), American sycamore (Platanus occidentalis), big-toothed aspen (Populus grandidentata), black birch (Betula lenta), black cherry (Prunus serotina), black gum (Nyssa sylvatica), black walnut (Juglans nigra), dogwood (Cornus spp.), Japanese snowbell (Styrax japonicus), maple (Acer spp.), oak (Quercus spp.), and paper birch (Betula papyrifera).

The adults and immatures of this species damage host plants by feeding on sap from stems, leaves, and the trunks of trees. In the springtime in Pennsylvania (late April - mid-May) nymphs (immatures) are found on smaller plants and vines and new growth of trees and shrubs. Third and fourth instar nymphs migrate to the tree of heaven and are observed feeding on trunks and branches. Trees may be found with sap weeping from the wounds caused by the insect’s feeding. The sugary secretions (excrement) created by this insect may coat the host plant, later leading to the growth of sooty mold. Insects such as wasps, hornets, bees, and ants may also be attracted to the sugary waste created by the lanternflies, or sap weeping from open wounds in the host plant. Host plants have been described as giving off a fermented odor when this insect is present.

Adults are present by the middle of July in Pennsylvania and begin laying eggs by late September and continue laying eggs through late November and even early December in that state. Adults may be found on the trunks of trees such as the tree of heaven or other host plants growing in close proximity to them. Egg masses of this insect are gray in color and look similar in some ways to gypsy moth egg masses.

Host plants, bricks, stone, lawn furniture, recreational vehicles, and other smooth surfaces can be inspected for egg masses. Egg masses laid on outdoor residential items such as those listed above may pose the greatest threat for spreading this insect via human aided movement.

For more information about the spotted lanternfly, visit this fact sheet: https://ag.umass.edu/landscape/fact-sheets/spotted-lanternfly.

• Emerald Ash Borer: (Agrilus planipennis, EAB) Since the New Year, the Massachusetts Department of Conservation and Recreation has confirmed at least 22 new community detections of emerald ash borer in Massachusetts. To date, 11 out of the 14 counties in Massachusetts have confirmed emerald ash borer. (The remaining counties where EAB has yet to be detected are Barnstable, Dukes, and Nantucket.) A map of these locations and others previously known across the state may be found here: https://ag.umass.edu/fact-sheets/emerald-ash-borer.

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). Adult insects of this species will not be present at this time of year. Signs of an EAB infested tree may include (at this time) D-shaped exit holes in the bark (from adult emergence in previous years), “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. Blonding on EAB infested ash has been particularly noticeable this winter in certain areas of Hampshire and Berkshire counties. Trees have been so heavily fed upon by woodpeckers that this change in the color of ash tree bark can be seen even while driving. (Monitoring for EAB this way is not recommended while operating your vehicle.) Particularly striking photos of blonding on ash caused by pileated woodpeckers were shared with UMass Extension from Lee, MA, courtesy of Cindy Packard on 2/13/2021. 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.

For further information about this insect, please visit: https://ag.umass.edu/fact-sheets/emerald-ash-borer. If you believe you have located EAB-infested ash trees, particularly in an area of Massachusetts not identified on the map provided, please report here: https://massnrc.org/pests/eabreport.htm.

• 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! This is excellent news, as it is data supporting the evidence that winter moth populations have decreased while the parasitic fly, C. albicans, has become established at many locations in New England. Dr. Joseph Elkinton’s laboratory at UMass Amherst has released this biological control 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. More information about the Elkinton Lab’s research and the biological control of winter moth can be found here: https://www.fs.fed.us/foresthealth/technology/pdfs/FHAAST-2018-03_Biology_Control_Winter-Moth.pdf

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

• Gypsy Moth:(Lymantria dispar) thanks to the gypsy moth caterpillar killing fungus, Entomophaga maimaiga, the recent outbreak of gypsy moth in Massachusetts has come to an end! Most locations in Massachusetts will not see damaging or even noticeable populations of this insect in 2021. Gypsy moth has been in Massachusetts since the 1860's. This invasive insect from Europe often goes unnoticed, thanks to population regulation provided by the entomopathogenic fungus, E. maimaiga, as well as a NPV virus specific to gypsy moth caterpillars. (And to a lesser extent many other organisms, including other insects, small mammals, and birds who feed on gypsy moth.) However, if environmental conditions do not favor the life cycle of the fungus, outbreaks of gypsy moth caterpillars are possible. (Such as most recently from 2015-2018, with a peak in the gypsy moth population in 2017 in Massachusetts.)

Check out Episode 1 of InsectXaminer to reminisce about the 2015-2018 outbreak of this insect: https://ag.umass.edu/landscape/education-events/insectxaminer

• 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 miles² 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.

• 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.
• Jumping Worms: In recent years, public concern about Amynthas spp. earthworms, collectively referred to as “jumping or crazy or snake” worms, has dramatically increased. University researchers and Extension groups in many locations in the US are finding that these species cause not only forest ecosystem disturbances, but may also negatively impact soil structure and reduce plant growth in gardens and managed landscapes. They do this by voraciously devouring the organic layer of the soil while feeding very close to the soil surface, unlike other species of earthworms. In woodland areas, they can quickly eat all of the leaf litter on the forest floor. Jumping worms also leave a distinct grainy soil full of worm castings. The soil becomes granular and may look like dried coffee grounds.

Unfortunately, there are currently no research-based management options available for these earthworms. So prevention is essential – preventing their introduction and spread into new areas is the best defense against them. Adult jumping worms can be 1.5 – 8 inches or more in length. Their clitellum (collar-like ring) is roughly located 1/3 down the length of the worm (from the head) and is smooth and cloudy-white and constricted. These worms may also wiggle or jump when disturbed, and can move across the ground in an S-shape like a snake. While the exact timing of their life cycle in MA might not be completely understood, their life cycle may be expected to go (roughly) something like this: they hatch in the late spring in 1-4 inches of soil, mature into adults during the summer and adults lay eggs sometime in August, and it is thought that their cocoons overwinter. (Adults perish with frost.) It is also worth noting here that jumping worms do not directly harm humans or pets. 
For more information, listen to Dr. Olga Kostromytska’s presentation here: https://ag.umass.edu/landscape/education-events/invasive-insect-webinars
Additional resources can also be found here: 
University of Minnesota Extension: https://extension.umn.edu/identify-invasive-species/jumping-worms
Cornell Cooperative Extension: http://ulster.cce.cornell.edu/environment/invasive-pests/jumping-worm
UNH Extension: https://extension.unh.edu/blog/invasive-spotlight-jumping-worms

Spring Scouting & Preparation for Upcoming Tree & Shrub Insects & Mites:  

• 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 overwintering bags. In certain areas across MA in 2020, increased populations of bagworms were observed and reported, particularly in urban forest settings and managed landscapes. More information can be found here: https://ag.umass.edu/landscape/fact-sheets/bagworm
• Balsam Twig Aphid: Mindarus abietinus overwinters as a silvery colored egg on host plant twigs. Eggs hatch just prior to budbreak and nymphs feed for a period of time on the undersides of last season’s needles before molting into a wingless stem mother. Stem mothers move to buds just as they open and give “live birth” to second generation nymphs. These second generation nymphs are the most damaging, feeding on new needles as they elongate, causing distortion and stunting. Excessive amounts of honeydew may be produced and cause needles to stick together. Foliar applications, if needed, may be made between 30-100 GDD’s, base 50°F on warm days before budcaps loosen. Inspect the twigs, near the base of needles of Balsam fir, Fraser fir, and other true firs for overwintering eggs and eventually the needles for feeding nymphs. This insect may be most problematic in Christmas tree production. In landscapes, many natural enemies can provide adequate management of this insect.
• 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.
• 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 or roughly the beginning of May.
• 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. Foliar applications may be made between 290-440 GDD’s. However, the damage caused by this insect is mostly aesthetic. Therefore, no management may be necessary.
• 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 148-290 GDD’s.
• Cooley Spruce Gall Adelgid: Adelges cooleyi is a native insect that has a complex life cycle. It has at least five different morphological forms, and requires 2 years and two hosts to complete its normal life cycle. Galls (pineapple shaped/cone-like and at the tips of twigs) are produced on Colorado blue spruce, Engelmann, Sitka, and Oriental spruce and cause needle injury (yellow spots and distortion) to Douglas-fir. Immature females overwinter on spruce near twig terminals. In the early spring, females mature into stem mothers and lay hundreds of eggs on lateral terminals. Upon egg hatch, nymphs migrate to new spring growth and feed at the base of growing needles. Immatures can be targeted on spruce between 22-81 GDD’s (mid-late April). On Douglas-fir, dormant oil applications should be made immediately before budbreak to avoid phytotoxicity. Follow all label instructions.
• 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). 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. Prune off and remove egg masses from ornamental host plants by early spring. 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. Dormant oil applications for this pest can occur according to label instructions in April, roughly between 7-120 GDD’s. 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.
• 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. Dormant oil applications can be made between 35-120 GDD’s or roughly from mid-April to early-May. For crawlers, early June timing is suggested between 533-820 GDD’s. (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.
• 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.
• 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. 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.
• 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

• 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. Mid-April to early-May (35-145 GDD’s) for dormant oil applications.
• Lily Leaf Beetle: Lilioceris lilii adults 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.) 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. Dormant oils can be applied between 7-35 GDD’s targeting the overwintering nymphs. Avoid applications to opening buds or blooms.
• Pine Bark Adelgid: Pineus strobi overwinters as an immature which begins feeding during the first days of warm weather in the spring and begins secreting white wax over itself, which can eventually coat the entire trunk of infested trees. Egg laying may begin in April. This insect can be found on the trunk, branches, twigs, and at the base of needles on new shoots. Spruce is a secondary host but this adelgid can repeatedly reproduce itself on pine. Wash off bark with a strong jet of water. If necessary, dormant oil applications can be made in mid-late April between 22-58 GDDs. Hosts include eastern white, Scots, and Austrian pines. This insect does little damage to healthy trees and can often be tolerated.
• 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. By April, females may move to twigs to complete the rest of their development. Dormant oil applications may be made between 22-121 GDDs. Follow all label instructions, as oil may remove the bluish color from certain conifers. 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 ununguis is 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. When damaging spruce spider mite populations are known from last season, dormant oil applications can be made (when temperatures are appropriate according to label instructions) between 7-121 GDD’s, base 50°F (April). 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.
• Viburnum Leaf Beetle: Pyrrhalta viburni is a beetle in the family Chrysomelidae that is native to Europe, but was found in Massachusetts in 2004. Viburnum leaf beetle overwinters as eggs laid in capped pits on the newest growth of susceptible viburnum branches. Scout for overwintered eggs and prune out and destroy before they hatch. Egg hatch occurs in late-April to early-May as temperatures warm and foliage becomes available. Monitor for larvae in mid-May (80-120 GDD’s). 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 at http://www.hort.cornell.edu/vlb/.
• White Pine Weevil: Pissodes strobi adults overwinter in sheltered locations in the leaflitter and become active very early in the spring, when daytime temperatures reach 50°F and before the bloom of forsythia (between 7-58 GDDs). Hosts include eastern white pine, Norway spruce, scotch, pitch, and red pine, blue spruce, and white spruce are also susceptible to white pine weevil damage. Adults will begin feeding on bark 7-10 inches below dormant terminal buds. Females will deposit eggs in terminal growth bark, and developing larvae will feed in leaders until they mature in July when pupation occurs in pupal chambers made of wood chips. Management in nurseries or Christmas tree production may be necessary. Target adults between 7-58 GDD’s.
• 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. 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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