UMass Extension Landscape Message #8
April 20, 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 April 27, 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: Raw, cold, wet and windy weather makes this April seem more like March. High winds occurring from Sunday night through Wednesday morning have brought down limbs and trees in many areas. Saturated soils are not helping! Plant development is creeping along, with Myrtle adding some color to the daffodils. Lawns are greening up despite the chilly temperatures and a scarce few buds of Forsythia are beginning to open. Pests/Problems: Wind damage to trees and shrubs from the Northeaster litters the landscape. Winter desiccation is showing up on Leyland cypress and arborvitae. To date, no evidence of a winter moth hatch has been observed.

Southeast Region (Hanson) - General Conditions: Cool, wet weather continued this past week with no increase in GDD (growing degree days) in two weeks. Hanson received 5.1 inches of rain, and some low areas are under water. High winds and rain over the weekend resulted in downed trees and fallen branches. Soils are wet. Cool weather continues to keep plant development in check. Some red maples and Pieris japonica are in full bloom, while others are just beginning, depending on location. Forsythia, saucer magnolia, and star magnolia buds are plump but not open. Warm weather is predicted this weekend, and hopefully spring will really arrive. Lawns have started to green up. Abeliophyllum distichum (white forsythia), Cornus mas, pussy willow, Helleborus niger, H. foetidus, H. x hybridus (formerly orientalis), Iris reticulata, Vinca minor and Scilla are in full bloom. Early daffodils, hyacinths, Pulmonaria, and Omphalodes verna have started to bloom in some areas.  Early flowering cherry trees are in bloom in Bridgewater and Quincy. Hamamelis mollis 'Pallida' and crocus are past bloom. Pests/Problems: Winter moth caterpillar eggs are still pinkish-red. They have not started to hatch here in Hanson; although if the weather is warm this weekend, they might be hatching soon. Ticks are active; conduct tick checks frequently, especially after yard cleanups. Chickweed and ground ivy are staring to bloom. Winter damage to Ilex opaca (American holly), Ilex glabra (inkberry), Ilex crenata (Japanese holly), Buxus sp. (boxwood), Meserve hollies, Euonymous fortunei, Rhododendron, and Kalmia continue to show up in the landscape. Deer continue to browse. Skunks are digging up lawns.

East Region (Boston) - General Conditions: Saturated soils.

Metro West (Waltham) - General Conditions: No report this week.

Central Region (Boylston) - General Conditions: Wet and cold. The soils are fully saturated and muddy.

Pioneer Valley Region ( Amherst) - General Conditions: Copious precipitation amounts are the big story in the Pioneer Valley this week, as with elsewhere in the state. Overall plant development and lawn green-up appear to be proceeding in slow motion. Many spring bulbs, which emerged during the last warm period, have yet to bloom. These observations are not surprising considering the cool temperatures, extensive rainfall, and lack of sunny days. No growing degree days were recorded in Amherst over the past two weeks. Pests/Problems: Mud and standing water are undoubtedly getting in the way of spring projects and delaying management practices. Several towns in the Connecticut River Valley experienced flooding at the beginning of this week. The Mill River at Northampton crested at 15.58 feet on April 16 (5.58 feet above flood stage) and shattered the previous record of 13.70 feet. Some areas at higher elevations received several inches of snow from the same storm. Tick activity remains high; remember to conduct tick checks after working outdoors.

Berkshire Region (Great Barrington) - General Conditions: No report this week.

ENVIRONMENTAL DATA -

The following growing-degree-day (GDD) and precipitation data was collected for a one-week period, April 12, 2007 through April 18, 2007. Soil temperature and phenological indicators were observed on or about April 18, 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 -

The cold and wet weather of the past week temporarily stalled most insect activity along with the development of plant growth. However, warm sunny weather should appear soon, which will most likely result in an explosion of insect activity and plant growth. Instead of easing into spring, we will most likely have it suddenly thrust upon us. Winter moth is right now on the verge of becoming active in all areas of the state where it exists. Hopefully, buds of host plants for the winter moth will experience fast budbreak and leaf expansion, which will limit feeding injury within the buds. The time for the use of dormant oil sprays has now passed in much of the state.

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. At budbreak, they begin to feed and cause galls to form. When in large numbers, countless new shoots will be killed. It may now be too late in many parts of the state for the use of dormant oil sprays; inspect buds and weather carefully.

• 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 two to three 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 : has been active all winter by feeding and developing at the base of needles on the twigs of our native and Carolina hemlocks. They are just now beginning to produce eggs. 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 a dormant oil spray when the weather allows for their use. It is not yet known what the effects of this winter’s weather pattern had on populations of this pest. There is some possibility that the warmer-than-normal December and January, followed by a sudden dip into very cold weather, has caused mortality of hemlock woolly adelgid in Massachusetts. We did witness this phenomenon a few years ago when up to 80% of this species was killed in certain areas. UPDATE: Now that egg-laying is well underway, we are seeing strong indications that HWA survived the winter weather and appears to be quite prolific, at least in western Massachusetts. Reports have not yet come in from other geographic areas.

Caterpillars:

• Winter Moth: An introduced pest, is expected 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. The eggs of this pest are on the trunks of trees now but are very difficult to see. Dormant oil sprays for the eggs may be effective for smaller plants, such as blueberries, which this pest also attacks. Once the foliage has expanded, treat with a spinosad product or Bacillus thuringiensis Kurstaki (B.t.K.), if necessary. If these warm days continue, we could see egg hatch within the next three weeks in Massachusetts. Deborah Swanson reports from Plymouth County that winter moth eggs have NOT yet hatched as of April 18, 2007. However, two unconfirmed reports have been received from Brookline, MA indicating that winter moth has begun to hatch and is now invading the buds of red maples. Sunny and warm temperatures in the 60s and 70s are expected by the weekend, which should greatly accelerate egg development and hatching. When the tiny oval, orange eggs turn color to a bluish-black, they are very near hatching time.

• Fall Cankerworm: A native caterpillar pest that is similar to winter moth, remains active in many of the same areas as winter moth. Eggs are in barrel-shaped clusters and wrapped around small stems. Treat the larvae the same as winter moth, once they appear.

• Forest Tent Caterpillar 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.
  
• Eastern Tent Caterpillar: a pest common to Malus and Prunus species, 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. If occurring in limited numbers, egg masses can be removed and destroyed (buried or burned). Once the larvae have begun to feed and form their silken webs, they can be treated with a spinosad product or Bacillus thuringiensis Kurstaki (B.t.K.).
  
• Bagworm caterpillar did manage to survive the Massachusetts’ winter and is now in the egg stage. Mostly, this pest comes into New England on plant material from more southern states, primarily on arborvitae and juniper, 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 Bacillus thuringiensis Kurstaki (B.t.K.) or a spinosad product for the caterpillars. Eggs hatch from late May into June.

Shoot Attackers:

• White Pine Weevil typically becomes active once we have accumulated 7 growing degree days (GDD) in Massachusetts. However, there are other circumstances that affect their appearance, such as snow cover and frozen soil. In many parts of Massachusetts, however, the snow is gone and the ground is no longer frozen. We are also well beyond the 7 GDD mark in those areas. It is assumed that this insect has found new terminal growth and has successfully laid its eggs. The time to treat has most likely passed in most parts of the state.
  
• Rhododendron Borer: Most affected rhododendron shoots now display signs of wilt and dying foliage. Don’t confuse this with winter-kill, 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 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 re-infestation.
  
• 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 phenological 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 re-infestation.

Nuisance Pests:

• Western Conifer Seedbug: A house invader, may start to appear in the living areas of homes now that the sun is getting higher in the sky and warming roofs and siding. These insects may have been in homes all winter but dormant. Now that spring is arriving, they become active and seek a route to the outdoors. However, they oftentimes 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.

Treat winter annuals and perennials in ornamental beds with glyphosate or glufosinate. These applications are easier if done before woody ornamentals leaf out. Non-herbicide material containing clove oil, citric acid, acetic acid, or orange extract can be used on small winter annuals but not large winter annuals or perennials. Control winter annual weeds before they set seed. Preemergence herbicides can be applied to weed-free ornamental beds now.

Reported by Randall Prostak, Weed Specialist, UMass Extension Landscape, Nursery and Urban Forestry Program, Amherst.

LANDSCAPE TURF

INSECTS -

Revisions to Massachusetts Pesticide Law - A reminder before the growing season gets going – there have been several changes to the regulations pertaining to use of pesticides to maintain turf in Massachusetts. The highlights include:

• The information that commercial pesticide applicators must leave at the residence now also includes the EPA registration number of any pesticide products applied.
• Prior to beginning each application, applicators must post signs on the turf intended for treatment and instruct the customer that the signs must remain in place for at least 24 hours after the application was made and must be removed within 72 hours after the application. (The 24-hour period is the new revision.)
• Golf courses are now required to post signs that have been approved by the Department of Agricultural Resources prior to any pesticide application. The signs must remain in place for at least 24 hours after the application and be removed within 72 hours of the application. The signs must be posted at the location where individuals register or sign in before beginning their round of golf, at the first tee, and at any other starting hole (e.g., tenth tee) on which applications are to be made. Note that posting on golf courses is now required in Massachusetts.

For more detailed information, download the following document:

333 CMR 13.06 Regulations Relative to the Use of Pesticides to Maintain Turf in Massachusetts (PDF 19K)

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

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 April 27, 2007.

This message is produced by the UMASS Extension, Landscape, Nursery and Urban Forestry Program. The copy is prepared by Dan Gillman 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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