UMass Extension Landscape Message #10
May 4, 2007

Quick Info Menu ------------------------------- SCOUTING INFORMATION REGIONAL NOTES - Cape Cod - Southeast - East - Metro West - 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 period April through June, this newsletter will be updated weekly. The next update will be available on May 11, 2007. 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-like conditions are the norm, with more clouds than sun and some fairly wet days. Temperatures are slightly cool to normal for this time of year. Plant development is progressing nicely, with early tulips and violets providing extra color in the landscape. Pests/Problems: Winter moth caterpillars have hatched and can be found in the emerging leaves of maples, crabapple, and other deciduous trees. Eastern tent caterpillar eggs have hatched, and small webs containing the caterpillars can be seen on the wild black cherry. Adult dog tick and adult deer ticks are active. Ground cover junipers and eastern red cedars are showing serious browning of last year’s foliage, with some of the ground cover junipers exhibiting extensive damage.

Southeast Region (Hanson) - General Conditions: Hanson received 1.5 inches of rain this past week, and soils are moist.  Lindera benzoin, Corylopsis paucifolia (Buttercup Winterhazel), Pieris japonica, Pieris 'Brouwer's Beauty,' Leonard Messel Magnolia, Helleborus orientalis, Helleborus foetidus, Corydalis solida, Pachysandra procumbans, tulips,  Dutchman's breeches, bloodroot, vinca, daffodils, Pulmonaria, Primula sp., trillium, anemones, Epimedium sp., Cherry 'Holly Jolivette,' and Pieris floribunda (Mountain Pieris), and Scilla sp. are in full bloom.  Turfgrass is green. Abeliophyllum distichum (White Forsythia) and Cornus mas (Corneliancherry Dogwood) are past bloom. Some of the weeping cherries that started to bloom last fall appear to have reduced bloom this spring, and Omphalodes did not blossom well this year. Pests/Problems: Winter moth caterpillars have hatched and have been found inside the developing buds of common lilac; American  beech; Norway, silver, red, Japanese, and sugar maples. Larch casebearer, wasps, hornets, ground-nesting bees, carpenter bees, ticks, mosquitoes, and eastern tent caterpillars are all active. Dandelions, violets, chickweed, ground ivy, and hairy bittercress are blooming. Deer continue to browse on apple trees, Chamaecyparis, tulips, and new foliage of hosta and daylilies.  The orange, jelly-like galls of cedar-apple rust are present on eastern red cedar.

East Region ( Boston) – No report.

Metro West ( Waltham) – General Conditions: Winter moth is active.

Central Region (Boylston) - No report.

Pioneer Valley Region ( Amherst) - General Conditions: The temperatures have been cool with several days of scattered showers, so the lawns are green and lush. Crocuses have faded, but the daffodils and tulips are more than making up for them. Actually, there is an abundance of flowering trees and shrubs showing off around the campus now, too. Pests/Problems: The cool, wet weather accompanying the onset of leaf and shoot growth make this a prime time for leaf spot and shoot blight fungal and bacterial infections to begin. Consider applications of fungicides and/or bactericides to minimize the impact of these diseases on susceptible high value plants.

Berkshire Region (Great Barrington) - General Conditions: Cool, cloudy weather for much of the past week. Soil moisture is high, but conditions for planting landscape materials are very good. Many ornamental trees and shrubs are now in bloom creating an astonishing spring landscape. Pests/Problems: Eastern tent caterpillar, carpenter bee, brown dog tick, and deer tick are primary pests observed this week. Deer browsing on tulips, daylilies, and other herbaceous and woody plants is still a big problem. Winter related damage to evergreens is apparent on rhododendrons and junipers in particular.

ENVIRONMENTAL DATA -

The following growing-degree-day (GDD) and precipitation data was collected for a one-week period, April 26, 2007 through May 2, 2007. Soil temperature and phenological indicators were observed on or about May 2, 2007. 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:

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.

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 -

Temperatures have remained a bit cool over the past week, but insect and plant activity have progressed noticeably since last week. Not too far south of the Massachusetts border, spring is roaring ahead at full speed and indicates that we will soon be seeing much new foliage and insect activity here in our state. Joe Elkinton’s lab and Deborah Swanson have reported that winter moth is believed to be now fully hatched and actively feeding on expanding foliage.

Adelgids: 

• Eastern Spruce Gall Adelgid on Norway and white spruces. Examine the base of healthy buds carefully with a hand lens for the presence of white cottony fibers and actual adelgids. These tiny aphid-like insects overwinter exposed at the base of buds. Prior to budbreak, they begin to feed and cause galls to form at the base of the expanding shoot. When in large numbers, countless new shoots will be killed. It is now too late for the use of dormant oil sprays.

• Cooley Spruce Gall Adelgid on blue spruce. This pest is very similar to the eastern spruce gall adelgid, but this one makes galls on blue spruce here in the eastern USA. If Douglasfir is within close proximity to a blue spruce, the problem can be severe. Oil sprays, of course, will cause blue spruce to become a dull green color for 2-3 months. In most cases, the blue color will eventually return to the needles, but clients should be informed ahead of time. Insecticidal soaps along with many of the registered chemical insecticides should also be effective against these soft-bodied and exposed insects during the early part of the season.

• Hemlock Woolly Adelgid : This pest has been active all winter by feeding and developing at the base of needles on the twigs of our native and Carolina hemlocks. They have already produced eggs for the new generation in the spring and are actively feeding and growing. Monitor with a hand lens for the presence of these tiny insects. Especially inspect twigs from the undersides for fine cottony masses, plump adelgids, and reddish-colored eggs. Treat with an oil spray when the weather allows for their use. This pest appears to have survived the atypical weather of this past winter and is now feeding and reproducing in large numbers.

Caterpillars:

• Winter Moth: We expect this introduced pest to be found in new areas this year as well in already established areas. Flight of the moths in December (mostly) was very spread out this year, and it was difficult to establish population sizes. However, those places that had winter moth last year, should be well prepared to deal with it this year. It is believed that all of the overwintering eggs have hatched, and the caterpillars are settled and feeding on expanding foliage. Once the foliage has expanded fully, treat with a spinosad product or Bacillus thuringiensis Kurstaki (B.t.K.), if necessary.

• Fall Cankerworm: This is a native caterpillar pest that is similar to winter moth. This pest remains active in many of the same areas as winter moth. Eggs are in barrel-shaped clusters wrapped around small stems. Treat the larvae the same as winter moth, once they appear. Oaks, among other deciduous hosts, are commonly attacked.

• Forest Tent Caterpillar - This pest has been on the increase in MA and other surrounding states for several years now. In areas of higher population densities, some mortality of this pest due to natural causes (such as disease) was seen in 2006. However, all areas where this pest occurred last year should be prepared to deal with forest tent caterpillar in 2007. Oaks in eastern MA seem to be the favored host while maples are the preferred host in western MA. However, this pest does have a rather wide deciduous host range overall.

• Gypsy Moth: Some areas witnessed natural decline of building populations last year due to the fungus, Entomophaga maimaiga. Monitor now for the tawny-colored egg masses to get a rough idea of population sizes. Once the eggs have hatched and the larvae have settled to feed, treat with a spinosad product or Bacillus thuringiensis Kurstaki (B.t.K.), if necessary. Eggs usually begin hatching when the shadbush (Amelanchier spp.) is in bloom. Gypsy moth eggs will be hatching any day now, if they haven’t already.
  
• Eastern Tent Caterpillar: Common to Malus and Prunus species, this pest overwinters as an egg that appears in a tight cluster and is wrapped around small stems of the host plant. Inspect for the presence of these eggs. The larvae have begun to feed and form their silken webs, which can be treated with a spinosad product or Bacillus thuringiensis Kurstaki (B.t.K.). This pest is now very active.
  
• Bagworm caterpillar - It did manage to survive the Massachusetts’ winter and is now in the egg stage. Mostly, this pest comes into New England on plant material, primarily on arborvitae and juniper, from southern states, and usually cannot survive our winters. This last autumn was mild well into November thus allowing these intruders to pupate, emerge as adults, and then produce upwards of 1000 per female. Inspect plants for the characteristic “bags,” which contain the eggs. When occurring in small numbers, remove by hand and destroy. If they occur in large numbers, wait until approximately mid to late June and treat with a Bacillus thuringiensis Kurstaki (B.t.K.) or a spinosad product for the caterpillars. Eggs hatch from late May into June.
  
• European pine sawfly - This pest will be active soon. Look for the female “wasps” laying their eggs within the needles of such host plants as mugo pine. Eggs appear as a row of blocky-shaped patches along the needles. They are often found in clusters on the plant. Small infestations can be pruned away and destroyed. The larvae feed in packed groups and can also be pruned away and destroyed. Larger populations can be treated with insecticidal soap (young larvae) or with a spinosad product.
  
• Larch Casebearer - Deborah Swanson reports that this caterpillar is now active and feeding on emerging foliage of the host plants. Treat with a product that contains Bacillus thuringiensis Kurstaki (B.t.K.) OR a spinosad product for the caterpillars.

Shoot Attackers:

• Rhododendron Borer: Most affected rhododendron shoots now display signs of wilt and dying foliage. Don’t confuse this with winterkill, which is also prevalent in much of the state. Inspect the base of injured shoots for entrance/exit holes and for piles of sawdust on the ground just below these holes. Prune out and destroy affected shoots. The larvae within the shoots are very mature and have plugged the holes with sawdust, so treatments in the spring are difficult. Specific pheromone traps can be hung in rhododendron plantings to monitor for the adult moths, which appear wasp-like, in mid-late May and through June. Use a knockdown spray for the adults when they appear. In July, if infestations are suspected, apply a coarse spray of beneficial (entomopathogenic) nematodes to the lower trunk and base of the scaffold branches.

Leaf Miners:

• Inkberry Leafminer - This pest overwinters within the mine in the leaf. Inspect for tip browning on foliage. This browning usually does not appear until late November or December and often goes unnoticed. If it is seen, it is usually attributed to winter injury. However, the browned part of the leaf should be rolled gently between the thumb and forefinger to feel the small lump within the mine that indicates a pupa of the inkberry leafminer. Leaf tips will also be hollow when torn open, if there is a miner present. Make a note to hang yellow sticky cards in early May to determine when the adult flies are emerging. That will be the time to apply a cover spray to prevent reinfestation.
  
• Birch Leafminer - As the old-time entomologists used to say, “When the birch leaves are about the size of a dime, it’s time to start thinking about the birch leafminer.” This adage turns out to be a good phonological indicator for the emergence of adult birch leafminers. The females require tender new foliage for oviposition (egg-laying). Make note of the white-barked birches that may have been attacked last year and hang yellow-sticky cards soon after budbreak, which will attract and catch the females. This strategy is not a control measure but rather an indicator for when to apply a cover spray to break the cycle of reinfestation.

Nuisance Pests:

• Western Conifer Seedbug: This house invader may start to appear in the living areas of homes now that the sun is getting higher in the sky, warming roofs and siding. These insects may have been in homes all winter but dormant. Now that spring has arrived, they are active and are seeking a route to the outdoors. Oftentimes they take a wrong turn and end up in the living room, sometimes in great numbers. Although relatively large insects (about 3/4”) they do not bite or sting. They can be vacuumed up and released outdoors or the bag containing them can be destroyed.

• Ladybugs: See the above description of Western Conifer Seedbug. The reasons for ladybugs being in homes and how to best deal with them are the same.

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

No report this week.

LANDSCAPE TURF

INSECTS -

No report this week.

DIAGNOSTIC SERVICES

UMass Laboratory Diagnoses for 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

NEXT UPDATE: The next issue will be available on May 11, 2007.

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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