UMass Extension Landscape Message #6
April 6, 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 13, 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: A wonderful spring weekend has given way to a return to more winter-like conditions. Cold rain and grey skies have put a damper on outdoor work. Snow and sleet are in the forecast. Fall fertilized lawns are just beginning to green up, and daffodils are beginning to open. Pests/Problems: Crows, grackles and starlings are pecking away at lawns in search of grubs, which are moving up into the root zone of turf. Winter damage is becoming apparent on rhododendron. Adult deer ticks are active.

Southeast Region (Hanson) - General Conditions: Cool weather, with some rain, has been the norm for this week. Approximately 1.75 inches of rain was recorded in Hanson. Cool weather has kept plant development in check. Forsythia buds are plump and yellow but not open. Lawns have started to green up. Cornus mas, pussy willow, crocus, Helleborus niger, H. foetidus, H. x hybridus (formerly orientalis), snowdrops, scilla, Iris reticulata, Hamamelis mollis 'Pallida' and Hamamelis x intermedia 'Arnold Promise' are in full bloom. Pests/Problems: Ticks are active; conduct tick checks frequently, especially after yard cleanups. Winter moth caterpillar eggs are pinkish-red and have not started to hatch. Deer continue to browse. Western conifer seed bugs and ladybugs are active indoors. 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. Skunks are digging up lawns.

East Region (Boston) - General Conditions: Cool and moist. Lots of willows are starting to bud out and flower. Especially pussy willows.

Metro West (Waltham) – General Conditions: Typical Boston area spring. Variable.

Central Region (Boylston) - General Conditions: Cold wet weather is putting a damper on spring, though the minor bulbs continue to bloom - even through last night’s snow. The earliest of narcissus are beginning to show color. Winter damage is apparent on many evergreens.

Pioneer Valley Region ( Amherst) - General Conditions: Hyacinths and crocuses are beginning to bloom in sheltered sites, while daffodils and tulips continue to poke ever higher out of the ground. The lawns are just beginning to truly turn green. Soil moisture is adequate. The Pioneer Valley received ~1/4 inch of rainfall this weekend, and more is falling outside the window as I write this report. Pests/Problems: There is evidence of winter drying and/or freeze damage on rhododendron, holly, leucothoe, and hemlock growing in sites exposed to south and/or west wind and sun. Deer ticks are active. Several people hiking in woods near Ware, MA found adult deer ticks on their clothing after returning home.

Berkshire Region (Great Barrington) - General Conditions: Cool weather is the trend for the time being, along with ample precipitation. Soil moisture is high. The cool temperatures have slowed plant growth, but on the positive side the flowers that come into bloom will persist for some time. Most minor bulbs are in bloom, and daffodils in sunny locations are near bloom. Helleborus niger is in bloom. Pests/Problems: Ticks are active, deer and rabbits are browsing, snow mold has been seen on many lawns, but there are no other prominent problems to report.

ENVIRONMENTAL DATA -

The following growing-degree-day (GDD) and precipitation data was collected for a one-week period, March 29, 2007 through April 4, 2007. Soil temperature and phenological indicators were observed on or about April 4, 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 during the past week have pretty much returned to what is to be expected for this time of year. Snow still remains on the ground in some parts of western MA. Overall, the snow is mostly gone, the ground is thawing (or thawed), and much mud prevails. Buds of certain trees are swelling, and the sugars and anthocyanins are returning to the branches and stems; budbreak for those early spring plants will be occurring soon. Rainy weather with temperatures in the low 40s (western MA) is expected to persist for at least a few more days. Once warm and sunny temperatures do arrive, expect to see a sudden burst of activity with those early spring plants and insects.

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 they occur in large numbers, countless new shoots will be killed. Treat before budbreak with a dormant oil spray, if necessary.

• 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 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 where 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: 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. 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 3 weeks in Massachusetts. Note: Deborah Swanson reports from Plymouth County that winter moth eggs have NOT yet hatched as of April 4, 2007.

• 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: 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. 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 a 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 is now active and seeking new terminal growth for egg-laying. The time to treat is now for preventing damage from this pest.
  
• 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 to 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.

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 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, 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: Visit the Landscape Message Archive for previous messages.

LANDSCAPE TURF

INSECTS -

White grubs are returning to the root zone and resuming their feeding. European chafers have been up for a couple weeks, but yesterday we even found a Japanese beetle grub in the top inch of soil from a sample taken in central Connecticut. The grub was quite close to a cart path, so the soil probably was a little bit warmer than surrounding areas. In any case, white grubs are on the move.

Chemical Updates . Keep in mind that there are two new products on the market that are in the same chemical class as imidacloprid (Merit™). Chlothianidin (sold as Arena™) was registered by the EPA last year, and has been registered by most of the New England states. The company claims the product is active against a wider range of insects than is Merit™. Certainly our trials have confirmed that it is very effective against oriental beetles, European chafers, and Japanese beetles. The other new product is thiamethoxam, sold as Meridian™. This product just received its federal registration in late January, and the company held a celebratory party at the Golf Industry Show in Anaheim in February. Syngenta claims the product is active against a wider range of insects than is Merit™. Field trials this year should determine just which insects should be on that list! (Previous work shows that Meridian™ is very effective against most white grubs.)

Note that Meridian has not yet been registered in some of the New England states, including Massachusetts, but registration is expected sometime during the growing season.

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 13, 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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