UMass Extension Landscape Message #7
April 17, 2008

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Quick Info Menu ------------------------------- SCOUTING INFORMATION REGIONAL NOTES - Cape Cod - Southeast - East - Metro West Waltham - Metro West Hopkinton - Central - Pioneer Valley - Berkshire ENVIRONMENTAL DATA PHENOLOGY WOODY ORNAMENTALS - Insects - Diseases - Weeds LANDSCAPE TURF - Insects - Diseases - Weeds INFO RESOURCES DIAGNOSTIC SERVICES Use this menu to instantly jump to any portion of the message!

The LANDSCAPE MESSAGE is an educational newsletter intended to guide landscape, nursery and urban forestry professionals in identifying pests in the landscape, monitoring their development, planning management strategies and creating site-specific records for future management reference. UMass Extension has updated this issue to provide timely pest management information and the latest regional news and environmental data throughout Massachusetts. During the months April, May, and June this newsletter will be updated weekly. The next update will be available on or about April 24, 2008. Missed a previous message? Visit the Landscape Message Archive. Interested in additional turf-oriented content? UMass Extension Turf Program Management Updates

SCOUTING INFORMATION BY REGION

REGIONAL NOTES -

Cape Cod Region (Barnstable) – General Conditions: Spring is progressing across the Cape.  'PJM' Rhododendrons in sheltered areas are beginning to bloom, along with the first dandelions and periwinkle.  Soil moisture is good, and it is a good time for transplanting deciduous trees and shrubs before they break bud.  Spring peeper choruses fill the evening air.  Pests/Problems: Asiatic lilies are poking out of the ground, soon to be followed by the bright red lily leaf beetle.  The first polistes wasps are flying in search of a nest-building site.  Dandelions and other early weeds are beginning to bloom. 

Southeast Region (Hanson) – General Conditions: Typical spring weather last week; some grey days, some sunny days.  Cooler weather has held some plant growth in check, so plants are coming into flower gradually, depending on location and microclimate.  Some nights below freezing.  Approximately 0.65 inches of rain was recorded in Hanson from April 8 - April 5.  Lawns have started to green up.  Forsythia, Pieris japonica sp., Pieris 'Brouwer's Beauty', Corylopsis spicata, Pieris floribunda, red maple, star magnolia, Cornus mas, pussy willow, crocus, Helleborus niger, H. foetidus, H. x hybridus (formerly orientalis), Corydalis solida, Abeliophyllum distichum (White Forsythia), Omphalodes, scilla, Pulmonaria sp., Vinca minor, hyacinths, early daffodils and early tulips, are all in full bloom.  Magnolia 'Leonard Messel'is just beginning to bloom.  Silver maple, Hamamelis mollis 'Pallida' and Hamamelis x intermedia 'Arnold Promise' are past bloom.  Pests/Problems:  Winter moth caterpillar eggs have not yet started to hatch in Hanson, MA, although with predicted warmer weather, they may be hatching soon. Ticks are active; conduct tick checks frequently, especially after yard cleanups.  Dandelions, chickweed and cress are in bloom.  The Plymouth County Extension office has received a few calls on black knot on cherry.  Deer continue to browse, as do rabbits.

East Region (Boston) – Pests/Problems: Cool and pleasant.  Transplanting from the nurseries is entering its third week at the arboretum where trees and shrubs are being dug and moved to their locations within the collection on the grounds.  Intermittent rains have helped with this.  Researchers at UMass Boston have been able to collect pollen samples from the following plants which are in bloom:  Acer x Freemanii, Acer rubrum, Alnus serrulata, Corylus americana, Corylus avellana, Lonicera korolkowii, Viburnum farreri 'Nanum', Cornus mas, Daphne mezureum, Erica carnea vivellii, Hamamelis x intermedia 'Arnold Promise', Magnolia stellata, Abeliophylum distichum, Jasminum nudiflorum, Prunus incise f. serrata, Salix gracistyla 'hagensis', and Ulmus x wilsoniana var. Japonica.  Pests/Problems:   Allergy season has begun.  Use care when working where poison ivy may be present as it may be hard to identify when leaves are not yet present.

Metro West (Waltham) – General Conditions: No report.

Metro West (Hopkinton) – General Conditions: Three barn swallows have returned from South America to the property a week earlier than usual this year.  Bright green lawns really make it feel like spring.  Okame cherries are clouds of pink buds right now.  Pests/Problems:  Deer ticks are active now.

Central Region (Boylston) – General Conditions: No report. 

Pioneer Valley Region (Amherst) - General Conditions: As the crocuses begin to fade, the daffodils are breaking into bloom.  Lawns continue to green up with cool temperatures and adequate soil moisture.  The flowering of the red maples and Corneliancherry dogwoods are at their glowing peak!  Pests/Problems:  With the recent warmth and rainfall, leaf spot and shoot blight fungal spores, as well as bacteria, blow and splash onto nearby young leaves and flowers.  As the spring develops, see the Disease Section of UMass Extension's Management Guide for Woody Ornamentals for specific management suggestions about some of the diseases common to New England.

Berkshire Region (Great Barrington) - General Conditions: Warm weather of the past week has initiated growth of many herbaceous perennials, bud swell of certain trees and shrubs, and greening of lawns, but has brought to a close the bloom period for snowdrops, winter aconite, and crocus in many areas of the county.  Soil moisture levels are high.  Pests/Problems:  Animal browsing, deer ticks, dog ticks are active.  Some winter desiccation seen on rhododendrons. 

ENVIRONMENTAL DATA -

The following growing-degree-day (GDD) and precipitation data was collected for a one-week period, April 9, 2008 through April 15, 2008.  Soil temperature and phenological indicators were observed on April 15, 2008.  Accumulated GDDs represent the heating units above a 50° F baseline temperature collected via our instruments from the beginning of the current 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.

PHENOLOGY -

The phenological indicators are a visual tool for correlating plant development with pest development. The following are the indicator plants and the stages of bloom observed for this period:

Indicator Plants - Stages of Flowering (begin, b/full, full, f/end, end)
PLANT NAME (Botanic/Common)	CAPE	SOUTH EAST	EAST	METRO W.		CENT.	P.V.	BERK.
				Waltham	Hopkinton
Magnolia stellata cvs. (Star Magnolia cultivars)	begin	b/full	full	*	begin	begin	begin	*
Forsythia x intermedia (Border Forsythia)	begin	full	full	*	full	*	*	*
R. mucronulatum (Korean Rhododendron)	begin	full	full	*	full	*	begin	*
Acer rubrum (Red Maple)	b/full	f/end	f/end	*	full	full	full	begin
Cornus mas (Corneliancherry Dogwood)	full	full	full	*	end	full	full	*
Pieris japonica (Japanese Pieris)	full	full	full	*	begin	full	full	*
Hamamelis mollis (Chinese Witchazel)	*	f/end	f/end	*	full	f/end	*	full
Acer saccharinum (Silver Maple)	end	f/end	f/end	*	end	*	end	*
* = no activity to report/information not available

CAPE COD REGION - Roberta Clark, Horticulturist for Barnstable County, Barnstable.

SOUTHEAST REGION - Deborah Swanson, Horticulturist for UMass Extension in Plymouth County, Hanson.

EAST REGION - James R. Allen, Horticulturist and Greenhouse Manager for UMass Biology Department, Boston.

METRO WEST REGION – James Martin, Consulting Arborist, reporting from the UMass Extension Center, Waltham.

METRO WEST REGION – Mark Sawyer, Horticulturist, Weston Nurseries, Hopkinton.

CENTRAL REGION - Joann Vieira, Superintendent of Horticulture, Tower Hill Botanic Garden, Boylston.

PIONEER VALLEY - Dan Gillman, Plant Pathologist, UMass Extension Plant Diagnostic Lab, UMass, Amherst.

BERKSHIRES - Ron Kujawski, Specialist, UMass Extension Landscape, Nursery & Urban Forestry Program, Amherst.

WOODY ORNAMENTALS

INSECTS -

Lepidopteran Caterpillars:

• Gypsy Moth - Numbers of this pest are expected to be low statewide in 2008.  Small problematic populations often pop up somewhere unexpectedly.  Monitor for viable egg masses now and tiny ballooning caterpillars.
  
  
• Forest Tent Caterpillar - After occurring in large numbers through out the greater Northeast over the past years, this native caterpillar species is now, once again, in low numbers due to natural controls such as the fungus, Entomophaga sp., and parasitoids such as certain flies.  Inspect now for viable egg masses.  In western MA this pest seems to prefer maples; in the eastern part of the state the primary host plants are oaks.  However, this caterpillar does have a rather large deciduous host range overall.
  
  
• Eastern Tent Caterpillar - Although in large numbers in recent years throughout New England, it is now in limited numbers due to natural controls.  Common on Malus and Prunus species, this pest makes large silken webs in the crotches of branches.  When in high population numbers, it is a serious defoliator.  Inspect for egg masses now to determine population size. 
  
• Fall Cankerworm - This is, also, a native species in declining numbers.  It prefers oaks but has a large deciduous host plant range.  Isolated pockets still exist.  In 2007 a defoliating population existed just north of Amherst in western MA.  Random and small populations will be active in eastern MA this year.  
  
  
• Winter Moth - Egg hatch is imminent.  Flight of the adult males was initially healthy last November in several eastern towns, but the earlier-than-normal snowfall may have impeded further emergence of the adults, which may have reduced the number of over-wintering eggs.  Eggs of winter moth are difficult to monitor.  They are small, oval and a light orange color and are often scattered on trunk bark.  As the embryos within the eggs near maturity, the eggs turn a deep blue color.  Upon hatching, the tiny larvae are carried upwards into the tree canopies mostly by air convection.  Once there, they seek swelling buds.  These tiny caterpillars then wriggle into the buds and begin to feed on foliage and flowers.  During years of high numbers, this pest can cause severe damage, especially if buds are slow to open due to cool weather.  Blueberries and apple trees can be sprayed with a dormant oil any time now (whenever the weather is conducive for oil sprays).  Once inside the buds, this caterpillar is very difficult to treat until the buds open and the larvae are exposed.  Work on the mass-rearing of the parasitic fly, Cyzenis albicans, continues in Dr. Joseph Elkinton’s lab at UMass Amherst.  More releases of this fly are scheduled for this spring in select areas in eastern MA.  Last year, parasitized winter moth larvae were recovered on Cape Cod at a site where Cyzenis had been previously released. 
  
  
• Winter Cutworm − Several reports have been received in the past two months from homeowners about the sudden appearance of numerous caterpillars on the surface of snow.  Birds have often been seen feasting on these larvae.  It is suspected that these caterpillars are a relatively new species here in the Northeast known as the Winter Cutworm Caterpillar (Noctua pronuba), which overwinter as partially grown larvae and are known to become active while temperatures are still rather cool and snow still exists on the ground.  They have a large host plant range which includes vegetables, grasses and ornamentals.   Often, they feed on grasses such as those growing in hay fields.  In large numbers they are quite destructive and often march across fields and roads like that of armyworm caterpillars when in search of food.  Michigan State University has a very informative fact sheet (PDF format), which is accessible at the following web site:
  http://www.greatlakeshybrids.com/2007/10/23/noctua-pronuba-in-michigan From this web page click on the link, Attached is a two- page brochure, to access the fact sheet.

Beetles:

• Lily Leaf Beetle - The bright red adults will be seen soon as they forage for newly emerging lilies.  Once found, the adults will begin feeding and mating.  Eggs will appear later in May on the undersides of foliage.  NEEM works well for the larvae, once they appear, but needs to be reapplied every 10-14 days.  Spinosad products also work well for the larvae.  Adult lily leaf beetle is best controlled with a pyrethroid insecticide.
  
  
• Viburnum Leaf Beetle is established in western MA (randomly throughout Berkshire County) and is expected to become a serious pest there.  It is expected that this pest will continue to expand its invasion of MA now given that it is in CT, RI, VT, NH, ME, and NY states.  Treat the same as for lily leaf beetle.  For current information about this pest, visit the Cornell web site at http://www.hort.cornell.edu/vlb

Piercing-Sucking Pests:

• Spider Mites - Inspect spruce, hemlock, fir, and others for the signs of last year’s feeding damage by these tiny but very prolific and potentially damaging pests.  Once found, inspect very closely for over-wintering eggs, which will require a good hand lens or microscope.  If found, treat with an oil spray OR with one of the new mite growth regulators that targets spider mite eggs. 
  
  
• Hemlock Woolly Adelgid - Due to the exceptionally cold winter of 2005, this pest is on the rebound in MA after several years of being in low numbers.  However, it reproduces quickly and not much else controls its number naturally here.  Inspect for the new cottony egg masses that have been appearing for the past couple of weeks.  Treat with a dormant oil spray now. 

Cool Stuff:

• Periodical Cicada − This unique insect only appears every 17 years in the adult stage.  Specific populations of these occur in the eastern USA as different broods that have peak years at varying times.  This year, it is Brood #14 that is peaking, and a part of that once large brood still exists on parts of Cape Cod.  As homeowners begin to rake their yards this spring, they will notice large round holes in the ground.  These holes are made by the nymphs as they take advantage of moist and pliable soil now to prepare an emergence hole that will get utilized in late May/early June.  At that time, millions of these nymphs will pour out of the ground, climb up on virtually everything, and molt for the last time into the large, red-eyed, winged adult cicadas.  This emergence brings much speculation about the remaining size of this population given the enormous development that has occurred on Cape Cod in recent decades.

Nuisance Pests:

• Ladybugs - the Multi-Colored Asian Ladybird Beetle (Harmonia axyridis) was introduced into this country decades ago to combat certain agricultural pests such as the pecan aphid in the Gulf States.  It, apparently, established itself quite well and now thrives in most states.  This particular species of ladybug (synonymous with "ladybird") is a dull orange color and has anywhere from zero to 19 black spots on its wing covers.  It is beneficial by feeding on pest insect species such as aphids and scales.  However, as is the case with most ladybug species, it seeks sheltered areas as over-wintering sites, such as rock cliffs, in the late fall.  Oftentimes, this species congregates on/in homes.  Lighter-colored homes that are exposed and those on hilltops seem to experience the worst infestations.  Houses are not a good choice for these ladybugs given that they are heated through the winter, and this often prevents them from entering into the dormant stage causing many of them to starve.  This ladybug does not bite nor sting people nor do they feed or breed indoors through the winter.  However, they have a natural defense mechanism known as "reflex bleeding" to protect themselves from danger.  Their "blood" is an orange color and has a rather offensive odor.  When disturbed (as by humans picking them up), they "bleed" this noxious liquid from their joints.  As mentioned above, it smells bad, and it can stain fabrics and wallpaper.  Therefore, vacuuming is the best solution.  When finished vacuuming, the bag should be remove from the cleaner and placed outside.  Otherwise, the ladybugs will just crawl out of the bag back into the home.  It is recommended that homes be inspected for holes in screening, which includes doors, windows, and attic vents.  Caulking around all of these points of entry should also be inspected and repaired if needed.  The ultimate key to managing these unwanted home invaders is to prevent them from entering in the first place.  If large numbers are being seen now on the outside of a house, the chances are good that they were within the house all winter, most likely in an attic, crawl space, under siding, or within the wall voids.  There are no traps available that I know of for catching these beetles.  Using a "pesticide bomb" within the house is not advised. These are ultimately our friends by feeding on the pest insects that are outdoors. 

Reported by Robert Childs, Entomologist, UMass Extension Landscape, Nursery and Urban Forestry Program, Amherst

LANDSCAPE TURF

INSECTS -

Spring White Grubs − After a long winter with seemingly interminable snow, spring finally seems to be making its way into New England.  Trees are beginning to bud, daffodils are beginning to show (at least in the warmer spots!), robins are chirping ... but of course that means the white grubs will not be far behind.

For those of you dealing with European chafers, you are already seeing grubs back in the root zone feeding actively.  As the frost leaves the soil, the other species will be feeding again very soon as well.  So I feel duty bound to discuss your options for controlling white grubs in the spring.  Your best bet, if you need to reduce grub populations in the spring, is to use trichlorfon (Dylox™).  But you will need to play a waiting game at this point and delay application until soil temperatures are 55° F or higher.  Remember that trichlorfon is sensitive to high pH, so if you are using a sprayable formulation, check the pH in the tank and amend it if necessary.  Also remember that trichlorfon cannot be used on school grounds in Massachusetts (and is also restricted in where it can be used in several other states beyond our "listening" area).

According to Dr. Albrecht Koppenhofer (Rutgers University), entomopathogenic nematodes are much less effective against spring grubs, so you might save those products until young grubs are just hatching and becoming active in August.

There are three insecticides in the neonicotinoid group that are now labeled for use in turfgrass: imidacloprid (recently went off patent but most familiar as Merit™); chlothianidin (Arena™); and thiamethoxam (Meridian™).  In addition there are two products that combine a neonicotinoid with a pyrethroid:  Allectus™ (Merit™ plus Talstar™) and Aloft™ (Arena™ plus a generic form of bifenthrin).
Some of these products are positioning themselves to provide "season long control", which of course implies that a spring application of the product would control white grubs that are present in the spring. But field trials conducted in several states have shown that spring applications of these materials normally do not control spring white grubs.

In areas of the country where the primary grub species is Japanese beetle or masked chafer, spring (April or May) applications normally are still active enough to control the grubs of those species as they begin to emerge in July.  Those early applications, especially of the combination products, no doubt would do a very good job of controlling, or at least suppressing, several other turf insects in a lawn-type setting−  things such as chinchbugs, billbugs, or caterpillars−throughout the summer.

But in New England, where our primary grub species are European chafers and oriental beetles, there may be times when we need to avoid the temptation to apply a neonicotinoid (whether alone or in a combination with a pyrethroid) too early.  I believe we run the risk of seeing a decline in performance against our European chafers and oriental beetles if we apply those products earlier than early June. Sometimes those "early" applications will hold and work fine in August, but I believe there are times when they will not.

So the bottom line is−if you have grub problems showing up now, either manage the damage (eliminate the rummaging four-legged varmints somehow!) or use trichlorfon to clean up the area.  Do not use a neonicotinoid yet−it will not touch the grubs you see right now.

Reported by Pat Vittum, Extension Entomologist, UMass Department of Plant, Soil and Insect Sciences, Amherst.

WEEDS -

DIAGNOSTIC SERVICES

UMass Laboratory Diagnoses Turf and Landscape Problems - Accurate diagnosis for a turf or landscape problem can often eliminate or reduce the need for pesticide use. The UMass Extension Plant Diagnostic Lab is available to serve commercial landscape contractors, turf managers, arborists, nurseries and other green industry professionals. It provides woody plant and turf disease analysis, woody plant and turf insect identification, turfgrass identification, weed identification, and offers a report of pest management strategies that are research based, economically sound and environmentally appropriate for the situation. Send specimens and payment (payable to the University of Massachusetts) to UMass Extension Plant Diagnostic Lab, Holdsworth Natural Resources Center, 160 Holdsworth Way, UMass, Amherst, MA 01003. The fee for a woody plant disease analysis is $50; the fee for turf disease analysis or nematode assay is $75. All insect, weed and turfgrass identification samples are $25 each. For more detailed submission instructions see http://www.umass.edu/agland/diagnostics

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

NEXT UPDATE: The next issue will be available on April 24, 2008.

This message is produced by the UMASS Extension, Landscape, Nursery and Urban Forestry Program. The copy is prepared by Anna Greene from data and reports provided by the staff and faculty of the UMass Landscape, Nursery and Urban Forestry Program and the UMASS Extension Turf Program as well as cooperating horticulturists and Green Industry professionals. The text is adapted for access via the Internet by Jason Lanier.

DISCLAIMER. This message is intended for commercial use. UMass Extension assumes no liability for recommendations. It is the responsibility of the applicator to verify the registration status of any pesticide BEFORE applying it. Different states have different regulations as well. The use of trade names (™) does not imply endorsement. Similarly, there may be other products you prefer to use.

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