UMass Extension Landscape Message #22
September 3, 2010

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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 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. The message will be updated bi-weekly throughout the months of August and September. The next update will be available on or about September 17, 2010. 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: The Cape continues on a hot and dry path in spite of approximately 2.5” of rain that fell over the two week period. Some part of the outer Cape reported higher amounts - up to 5” in Orleans. All eyes are on Hurricane Earl, which should approach the Cape and Islands late Friday night of the Labor Day weekend. Pests/Problems:  Typical late season problems are here. Lots of powdery mildew on anything that is susceptible. Many trees, shrubs, and perennials are exhibiting  signs of drought stress. Most of the insect pests in the landscape have come and gone and it is time to start the fall clean up.

Southeast Region (Hanson) – General Conditions: Hanson received 6.6 inches of much needed rain over the past two weeks. More rain is expected this Friday from Hurricane Earl which is reportedly coming close to SE Mass.  Despite the rain, many plants continue to exhibit signs of drought stress as evidenced by premature leaf drop and early fall color. More rain is needed. Many unirrigated lawns look to be in bad shape. Temperatures continue in the high 80’s and low 90’s. Rose-of Sharon, landscape roses, Hibiscus ‘Copper King’ and other perennial hibiscus, Clerodendron trichotomum, Hydrangea paniculata, butterflybush, Caryopteris sp., Sedum sp., many ornamental grasses, Rudbeckia trilobum, Perovskia atriplicifolia (Russian Sage), Corydalis lutea, Rudbeckia fulgida ‘Goldsturm,’ Physostegia, Chelone, Coreopsis ‘Harvest Moon’,  goldenrod, Hosta plantaginea and other late blooming Hosta , Joe-pye-weed, and Lobelia syphilitica are in full bloom. The fruit of autumn olive (invasive), crabapple, Staghorn sumac, Kousa dogwood, and Viburnum are also providing landscape color. Pests/Problems: Dogwood sawfly, earwigs, slugs, aphids, mites, snails, lacebugs, ticks, deer flies and mosquitoes are all active. Be on the lookout for ground-nesting wasps as well as wasps nesting in bushes and trees.  Deer are browsing and reports have come in of increased vole, chipmunk, field mice and squirrel activity. It appears to be a good year for rodents. Powdery mildew continues to be found on a wide range of plant material.  Giant tar spot is showing up on Norway maple. Leaf blotch of horse chestnut, caused by the fungus Guignardia aesculi, is rampant . This is a common disease which causes the leaves to turn brown. Poison ivy is having a great year along with crabgrass and other weeds. Goldenrod and ragweed are in bloom.  Pollen from ragweed may cause allergies in some people, but goldenrod is often mistakenly blamed.  Remind clients, that if they prune spring flowering shrubs now (lilac, rhododendron, forsythia, azalea, etc.) that they will most likely reduce the number of flowers next spring. Also, remind clients to continue to water landscape plants that were planted this season or plants that were damaged by winter moth caterpillars.

East Region (Boston) – General Conditions: We received 6.03 inches of rain between the 22nd and 25th of August while the Blue Hills Observatory (BHO) recorded 7.3 inches of rain during this same period. For the BHO, this was the second greatest single rainfall event for the month of August since 1955 when they received 12.77 inches of rain. Despite this event last week, the soil has dried considerably due to the 5 day heat wave with temperatures reaching over 90 °F. Vines in bloom include: Bignonia capreolata, Campsis [C. radicans (Trumpet creeper), C. grandiflora (Chinese Trumpet Vine), C. x tagliabuana], Clematis [C. maximowicziana (Sweet Autumn Clematis), C. vitalba (Pilgrim's Clematis)], Cocculus trilobus (Japanese Snailseed), Lonicera [L. x heckrotti (Everblooming Honeysuckle), L. periclymenum (Woodbine Honeysuckle), L. sempervirens (Trumpet Honeysuckle)] and Wisteria macrostachya ‘Blue Moon’ (Wisteria). Shrubs in bloom include: Callicarpa kwangtungensis (Chinese Beautyberry), Calluna vulgaris (Scotch Heather), Calycanthus sp. (Sweetshrub), Caryopteris x clandonensis (Bluebeard), Ceanothus x pallidus, Clematis heracleifolia var. davidiana (Hyacinth-flower Clematis), Clerodendrum trichotomum (Harlequin Glorybower), Daphne x transatlantica (Daphne), Elsholtzia stauntonii (Mint Shrub), Erica vagans (Cornish Heath), Hydrangea [H. arborescens (Smooth Hydrangea), H. quercifolia (Oakleaf Hydrangea)], Indigofera [I. kirilowii (Kirilow Indigo), I. pseudotinctoria (Indigo)], Kerria japonica (Japanese Kerria), Lavandula angustifolia (English Lavender), Lespedeza bicolor (Shrub Bushclover), X Phylliopsis ‘Sugar Plum’ , Rhus [R. chinensis (Chinese Sumac), Rhus copallina (Shining Sumac)], Viburnum [V. plicatum f. tomentosum (Doublefile Viburnum), V. sargentii ‘Onondaga’ (Sargent Cranberry Bush)], and Wikstroemia trichotoma (Wikstroemia). Aconitum sinomontanum (Monkshood) is blooming as the late flowering Koelreuteria paniculata (Golden Rain Tree) continues to hold its blossoms. Pests/Problems: Weeds continue to flourish thanks to the 4 days of rain followed by 5 days of heat. Weeds in bloom include: Aster pilosus, now Symphyotrichum pilosum (Wood Aster), Cyperus esculentus (Yellow Nutsedge), Oxalis stricta (Yellow Wood Sorrel), Taraxacum officinale (Common Dandelion). A white glaucous caterpillar has been spotted defoliating various dogwoods including Cornus alba. New plantings continue to show signs of water stress.

Metro West (Waltham) – General Conditions: Total rainfall for the month of August was 3.79”, which exceeded the historical rainfall average of 3.54” for the month. A good amount of that rain, 3.54” fell within a four day period falling beginning on August 22nd and ending on the 25th.  Eight days were recorded for the month of August with temperatures into the 90’s.  The highest temperature of 95° was recorded on the last day of the month.  The coolest temperature for the month was recorded on the 28th with a low of 49°.  Foliage has begun to turn on some trees such as Acers (Maples) and Nyssas (Tupelos). Pests/Problems:  Continue to monitor soil moisture and continue to scout for the Asian Longhorned Beetle because it is still active!

Central Region (Boylston) – General Conditions: Three days of cooler temperatures and gentle rains last week provided short relief from the hot dry conditions -  which have now returned. Soils are dry once again, and lawns are beginning to show drought stress again. Many trees and shrubs are taking on fall foliage hues prematurely and/or dropping leaves.
Pests/Problems:  Fall Webworm is abundant. 

Pioneer Valley Region (Amherst) - General Conditions: During the last two weeks, the Pioneer Valley had variable weather from cool and cloudy with occasional drizzle to hot, dry and another heat wave. Now Hurricane Earl on its way to cool things down again and possibly bring rainfall by the end of the week. Soil conditions are very dry. Soaking irrigations of recently transplanted woody plants can be critical to their survival. In addition, a cooling 2-3 inch layer of composted mulch over their root zone is helpful to retain soil moisture.

Berkshire Region (Great Barrington) - General Conditions: Hot, humid, and dry weather continue to characterize this year’s growing season.  Despite occasional downpours, soils remain very dry since showers tend to be brief and with so much volume that most precipitation runs off soil surfaces rather than infiltrating the soil.  Even where soils do absorb some moisture it quickly evaporates with the persistent hot weather and wind.  However, conditions may change soon in the wake of hurricane Earl and a cold front moving in from the northwest. Pests/Problems: Premature fall color and leaf drop is still an issue for many trees and shrubs. Wasps are at their peak population and most aggressive state at this time of year. Caution is advised when working outdoors. Leaf tiers continue to be active on many plants, woody and herbaceous. Powdery mildew is the prominent disease in the landscape though leaf spot infections are very apparent.  Though direct pest and disease control is not warranted in most cases this late in the season, landscape managers should still take note of these in order to plan control measures next spring.  Examine landscape plants now and identify damage from specific diseases and pests.  Many should be obvious, e.g. white pine weevil damage to leaders on pines and spruce, spruce gall caused by adelgids, stippling on needled evergreens and other plants caused by spider mites,  leaf spots, botrytis, and powdery mildew. Where diseases have occurred, management begins now with good sanitation.

ENVIRONMENTAL DATA -

The following growing-degree-day (GDD) and precipitation data was collected for a two-week period, August 5 through August 18, 2010.  Soil temperature and phenological indicators were observed on or about August 18, 2010.  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

Phenological indicators are a visual tool for correlating plant development with pest development. The following are 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.
Heptacodium micinioides (Seven-Son Flower)	begin	begin	begin	begin	begin	*	*
Clematis paniculata (Sweet Autumn Clematis)	begin	begin	begin	b/full	end	*	begin
Polygonum cuspidatum (Japanese Knotweed)	f/end	full	b/full	begin	b/full	full	full
Sophora japonica (Japanese Pagodatree)	end	*	end	b/full	end	end	*
* = no activity to report/information not available

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

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

EAST REGION - Kit Ganshaw & Sue Pfeiffer, Horticulturists, reporting from the Arnold Arboretum, Jamaica Plain.

METRO WEST REGION – Julie Coop, Horticulturist, reporting from the UMass Extension Center, Waltham.

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

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

BERKSHIRE REGION - Ron Kujawski, Horticultural Consultant, reporting from Great Barrington.

WOODY ORNAMENTALS

INSECTS -

Asian Longhorned Beetle - With approximately 25,000 trees having been surveyed within the epicenter of the initial find of ALB in Jamaica Plain and no new finds of ALB being detected, survey work there is now being scaled back. Thus far, only 6 red maples at Faulkner Hospital, which were quickly removed and destroyed on July 6th, 2010 have been the only positive finds in that Regulated Area. In the Worcester Regulated Area, survey work and removal of infested trees continues. MDAR has issued the following: "It is extremely important that we get the word out ASAP to everyone in the Boston, Brookline and Newton area to be on the lookout for: Adult Asian longhorned beetles (shiny black beetles with white spots and long, banded antennae). ALB exit holes (dime-sized, perfectly round holes, especially in maple, but also in birch, elm, horsechestnut, willow and other hardwood trees…but not oak). ALB egg-laying sites (divots in the bark ranging in size from 1/4 to 3/4 inches across – fresh pits often have oozing, foaming sap). Anyone seeing anything suspicious should report it immediately at http://massnrc.org/pests/albreport.aspx or toll-free: 1-866-702-9938. Take photos if you can. If you are with an environmental group or other organization that needs outreach materials, we will provide you with ID cards, fact sheets, etc., for free. Just contact Jennifer Forman-Orth by phone or email: 617-626-1735 or jennifer.forman-orth@state.ma.us Spread the word, not the beetle! Get all the latest ALB news at: http://massnrc.org/pests/alb" Asian longhorned beetle adults are still in the peak of their activity cycle. Be consciously looking for this insect, new exit holes, sawdust, and egg-laying sites. Report ASAP if found. To know how to properly identify ALB and its signs, refer to the following fact sheet: How to Recognize Asian Longhorned Beetle

Viburnum leaf beetle - The adult beetles remain very active.   Adult beetles are capable of defoliating host plants.  Treat adult beetles with a labeled pyrethroid or organophosphate insecticide when they appear.

Japanese beetle adults remain active but their numbers are waning.

Fall Webworm caterpillars have finished their feeding activity.

Mimosa Webworm remains active and tying together the foliage of honeylocust, primarily. This caterpillar will feed into the fall by using silk to make loose ‘pouches of leaflets’, which it then skeletonizes. If population size is large, entire trees can appear ‘bronzed’ by late August into September from the dead foliage. If necessary, treat with a product that contains Spinosad. However, most damage from this pest has already occurred.

Rose of Sharon Moth (aka: Hibiscus caterpillar) (Anomis commoda) remains actively feeding, especially on Rose of Sharon.  This caterpillar is cryptically colored and often rests with its body pressed against and parallel to the stems. If foliage displays large notches of feeding damage (don’t confuse with the skeletonizing of Japanese beetle) then inspect very carefully for this caterpillar, which is hard to find. If touched or handled, this caterpillar will thrash wildly but is harmless. Large populations are capable of completely defoliating plants. If necessary, treat with a product that contains Spinosad or with one of the registered pyrethoid insecticides.

Red-headed Pine Sawfly larvae are active. These yellow larvae have black spots and a rust-colored head capsule. They feed in clusters, typical of most of the pine sawfly species. If temperatures remain mild, this pest can feed well into October and cause much defoliation damage. Treat larvae with a product that contains Spinosad.

Dogwood Sawfly is very active. This larva is yellow with black spots but it is usually covered with a white pubescence that makes it resemble a bird-dropping on the foliage and stems of host plants.  This pest feeds through September and can create much damage.  Treat with a product that contains Spinosad.

Pearslug Sawfly remains active on such hosts as cotoneaster and ornamental plum, among others. The larvae are a shiny, black color and resemble slugs. This pest sits on top of the foliage and scrapes away leaf tissue. Large populations are capable of causing most of the foliage of the host plant to appear bronzed as if killed by fire.  This insect will feed well into September. Treat with a product that contains Spinosad.

Hemlock Woolly Adelgid remains dormant as nymphs settled on the small stems. Horticultural oil sprays can still be applied but manufacturers warn to avoid treatments on days where the temperatures are above 85-90 degrees. Applications of systemic imidacloprid is effective, as well, but soil applications may take 2-3 months before they are fully systemic within a large tree. Also, avoid applications while the weather is hot and dry. Feeding will resume in mid-October.

Tuliptree Scale females are feeding and maturing on the stems and branches of tuliptree and magnolia. Currently, they are about ½” long, oval, covered with a light white pubescence with the body beneath being a light pink color. Heavily infested trees will have problems with sooty molds and will be attractive to large numbers of hymenoptera (ants, bees, wasps) interested in feeding on the honeydew exuded by the scale insects. Systemic applications of an Imidacloprid product may be warranted for large populations.  This scale has one ladybug predator that resembles a mealybug in its larval stage. It is not uncommon to find these mixed in with the scale populations on magnolia and tuliptree.  Do not confuse these beneficial insects with that of a mealybug pest. 

Two-spotted Spider Mite remains active on a variety of host plants. This warm-season spider mite species will only become more prevalent as warm to hot weather continues. Inspect for chlorotic foliage that is finely stippled. Mites can be found primarily on the leaf undersides. Under current weather conditions, populations of this mite can suddenly become extremely large and destructive.

Lacebugs on Shrubs are actively feeding. Plants growing in sunny locations are at a higher risk for attack. Soil applications of a systemic imidacloprid product may still be applicable at this time as long as irrigation is available to keep soil moist during the uptake period. Inspect such plants as: Japanese andromeda, azalea, rhododendron, hawthorn, and others. Hot and dry weather drives lacebug populations to large numbers quickly.

Reported by Robert Childs, Extension Entomologist, Plant, Soil and Insect Sciences Department, UMass, Amherst.

LANDSCAPE TURF

INSECTS -

Webworms, crane flies, and grubs, Oh My!

As we enter September, we can hope the hot weather will finally break for good - and that Hurricane Earl will stay well east of Cape Cod. But late summer is the time when we can expect to see several turf insects in a variety of settings.

Invasive crane flies

A year ago invasive crane flies (the "marsh crane fly", Tipula oleracea) were confirmed on Martha's Vineyard and in Falmouth. You may still be seeing some adults flying in those areas. The adults look like giant mosquitoes. (Remember that there are also many native species of crane flies that fly at this time of year, so just because you see crane flies is not necessarily cause for panic.) The adults will be laying eggs soon. The eggs survive better in areas where the soil is moist - so if the hurricane drops a lot of rain in southeastern Massachusetts, that might increase the likelihood of those eggs surviving. The immatures (kind of leathery looking, often an olive green or gray color), will feed into November most years, and can feed through the winter months if temperatures are mild. They will complete their development next spring (sometimes as early as April), adults will emerge, and produce eggs for another generation.

There have been very few field trials conducted on this species of crane fly, but there appear to be many options. One approach is to treat affected areas just as larvae are hatching out of the eggs (likely to be mid to late September this year). Several classes of insecticides have been used with success in New York and Washington State, including neonicotinoids, pyrethroids, and the new insecticide from DuPont (chlorantraniliprole). Refer to the Professional Guide for IPM in Turf for Massachusetts for details. Follow the application with water, to enhance contact with the subsurface larvae.

Webworms

Right on schedule, sod webworm adults are flying in large numbers in my own back lawn. I always see the moths flitting about in late afternoon or evening at this time of year, when I am mowing, and I am always impressed at the large numbers of moths. But to date I have never seen any damage caused by the webworm larvae that would have been feeding in the previous two to three weeks. While some turf managers do experience damage from webworms during the summer, most areas do not experience populations that warrant treatments. Furthermore, as we are approaching late summer and early autumn, surely we will get a break from the beastly hot temperatures, and our cool season turfgrass should be able to begin to recover from this record-breaking summer.

White grubs

This is an excellent time to monitor for white grub activity. Because the summer was so hot and dry in most locations, you might find that grubs are more active in areas that retain moisture better (heavier soils, low lying areas, areas near leaky sprinkler heads). Remember that ordinarily European chafers do better in dry conditions than our other main species (Japanese beetles and oriental beetles). Also keep in mind that some Japanese and oriental beetle females may have delayed egg laying because soils were so dry in so much of the region. So you may see some fairly small grubs, along with the more typical second instars, in many locations.

For turf managers who must comply with the Massachusetts Children and Families Protection Act, it is really important that you monitor for grub activity NOW. Products that contain trichlorfon are often used to reduce early autumn grub populations but the law prohibits use of those products on certain school grounds and athletic fields. However, we conducted studies a couple of years ago and found that two of the neonicotinoids currently available on the turf market did reduce grub populations, even when applications were not made until mid September. The products did not lower grub counts nine days after application, but when we came back and looked 30 days after application, grub counts had been reduced significantly. The applications that "worked" were products that contained chlothianidin or thiamethoxam. Note that imidacloprid did not reduce grub counts significantly, even 30 days after the September application.

The message - if you need to rely on a neonicotinoid to reduce this fall's grub populations, the earlier you make the application, the more quickly it will work (and the more skunk damage you will avoid!). Remember to follow the application with at least 0.1 inch of water, 0.25 inch is better.

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

AGRONOMY -

The dry conditions and high heat of this summer season have taken a visible toll on many lawn areas. Although some dormant turf is beginning to recover, lasting damage from drought and heat, insects, and disease is common. At this time and in the coming weeks, the timing is optimum for repair and re-planting of such affected areas. Refer to the following fact sheet for detailed information to help with upcoming renovation and overseeding projects.

Lawn Renovation and Overseeding Fact Sheet (PDF 96K)

Submitted by the UMass Extension Turf Program

IMPORTANT INFORMATIONAL RESOURCES

For a complete listing of upcoming events, see our Conferences and Workshops page.

Don't forget to visit the UMass Extension Online Weed Herbarium!

Late Blight was positively identified in Hadley, MA on July 20. Home gardeners should be on the lookout for Late Blight symptoms on tomato and potato plants. Check out our 2010 Information Clearinghouse on Late Blight of Tomato and Potato , maintained by the UMass Extension Vegetable Program.

Visit the Network for Environmental & Weather Applications (NEWA) web site for pest information, crop management information, and weather and climatic information (including GDDs) for a network of reporting stations throughout NY, VT and MA.

NEW! Pest Identification Guide for Weeds, Insects and Diseases of Woody Ornamentals - Good identification of your pest problem is the first, key step to successful management! This photo guide has over 80 pages of clear color photographs for the most frequently encountered weed, insect, disease and nonpathogenic disorders of ornamental trees and shrubs in the Northeast. Click here to order online from the UMass Extension Bookstore or contact (413) 545-0895; eweeks@umext.umass.edu for information.

NEW! 2010-2011 Professional Guide for IPM in Turf for Massachusetts - This guide is intended for use by professionals as a tool in the management of all types of turf: from lawns, to fine playing surfaces, to utility areas. The principles presented are adaptable to a wide range of management schemes: from organic, to low-maintenance, to high-intensity maintenance for premier turf sites. Click here to order online from the UMass Extension Bookstore or contact (413) 545-2965; jdlanier@umext.umass.edu for information.

DIAGNOSTIC SERVICES

A 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. 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 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/soiltest Alternatively, call the lab at (413) 545-2311.

NEXT UPDATE: The next issue will be available on or about September 17, 2010.

This message is produced by the UMass Extension, Landscape, Nursery and Urban Forestry Program. The copy is prepared by 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 compiled and 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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