UMass Extension Landscape Message #3
March 3, 2006

Quick Info Menu ------------------------------- ENVIRONMENTAL DATA REGIONAL NOTES - Cape Cod - Southeast - East - Central - Pioneer Valley - Berkshire PHENOLOGY WOODY ORNAMENTALS - Insects - Diseases - Lab Report - Weeds TURFGRASS - 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. The next update will be available on Friday, March 17, 2006. Missed a previous message? Visit the Landscape Message Archive. Interested in additional turf-oriented content? UMass Extension Turf Program Management Updates

ENVIRONMENTAL DATA

The following growing-degree-day (GDD) and precipitation data was collected for a three-week period, February 8, 2006 through March 1, 2006. Soil temperature and phenological indicators were observed on March 1, 2006. Accumulated GDDs represent the heating units above the 50° F baseline temperature collected via our instruments since the beginning of the current growing season. This information is intended for use as a guide for monitoring the developmental stages of pests in your location and planning management strategies accordingly.

REGIONAL NOTES

Cape Cod Region (Barnstable) - General Conditions: Winter returned to the Cape in February, with only a day or two of milder weather. Two snow events added up to slippery roads while frigid temperatures certainly slowed down plant development. ‘Arnold Promise’ witchhazel is in full bloom, along with snowdrops. Pests/Problems. No pest activity to report. Clean-up continues on wind-damaged trees.

Southeast Region (Hanson) - General Conditions. Like December, February saw intermittent rain and snow and even some spring-like days. Temperatures ranged from daytimes in the 50's to 6 degrees at night. Several days in the month were above 50, and some towns saw 60 degrees on February 16. Hanson received 12" of snow on February 12 and 3" of snow on the 26th. Helleborus foetidus is beginning to bloom. Winter aconites and snow drops started to bloom in early February, along with Hamamelis 'Arnold Promise' and 'Pallida.' The fruit of cranberry viburnum, the berries of many hollies, and the bark of Acer griseum are providing much needed color and interest in the winter landscape. Hanson received approximately 2 inches of rain. Pests/Problems. Deer continue to browse.

East Region (Boston) - General Conditions: The coldest day of the year occurred on Monday, the 26th of February, with a morning temperature of 7 degrees F. Snowdrops, hyacinths, and daffodils were beginning to come up. Pests/Problems. No pest activity to report.

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

Pioneer Valley Region (Amherst) - General Conditions. The first half of February was generally above normal in temperature while the second half was a bit below or about normal in temperature. There were also several days with significant amounts of rainfall during the first week of the month, along with a dusting to several of inches of snow on the last weekend of the month. Pests/Problems. With the return of winter conditions to the Pioneer Valley, scouting around the UMass Campus revealed no insect or disease problems in the landscape. There was concern that with the relatively warm January and early February weather the buds on some plants might break bud early. However, the buds on deciduous trees and shrubs appear dormant at this time. Nonetheless, because of the sudden return to winter, there might be damage to plants due to lack of hardiness as the weather warms during the next month and the evidence of this condition becomes visible.

Berkshire Region (Great Barrington) - no report

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.

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

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

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

WOODY ORNAMENTALS

INSECTS

Winter moth flight is over, but the eggs are now waiting for spring to hatch. Currently, the eggs are small, oval, and a rather drab color. Very soon, these eggs will turn orange. These can be found on the trunk and branches throughout a tree. Monitor now for the presence of winter moth eggs. This exotic pest has been recently shown to be far more prevalent than previously understood. Most of eastern MA, all of RI, some spots in southeastern NH, southeastern CT, southern NH, and certain areas along the Maine coast have this pest. The highest population numbers, by far, are in MA and RI.

Gypsy moth is expected to be in high numbers in MA, and other Northeastern states. The fungus, Entomophaga maimaiga, that controls gypsy moth naturally has not performed well during the past two springs. This is primarily a function of spring weather conditions; rainy periods at critical times during the caterpillar stage are essential for the spread of this pathogen to gypsy moth caterpillars.

Eastern tent caterpillar is once again expected to be in large numbers and attacking their favored host plants of apple and cherry.

Forest tent caterpillar is also expected to be in large population numbers once again in MA and other surrounding states. Last year, this pest caused more than 200,000 acres of defoliation in MA. Forest tent caterpillar has been a problem in eastern MA for several years, primarily on oaks, but it is now building in serious numbers statewide, as well as in VT, on sugar maple as well.

Fall cankerworm is expected to be in large numbers in eastern MA, and on Long Island in 2006. Parts of RI may also experience some of this pest’s activity.

Hemlock woolly adelgid has been actively feeding since last October and is now about to start laying eggs. This will be the time when the cottony masses that surround the eggs will be most visible, especially from the undersides of the branches. Make note of those plants that will require treatment with oil sprays once the correct weather conditions prevail.

Spruce spider mite from last fall has not yet shown up yet. It will “suddenly” become apparent on those affected plants, but no mites will be seen at that time. However, make note of those plants that were inured from last fall’s feeding and expect to have more mites on those plants this spring. Once the correct weather conditions prevail, treat with an oil spray or, if eggs are present, they can be treated with one of the mite growth regulators that has ovicidal activity.

Trees and shrubs. The spring of 2005 was wet in many parts of New England and resulted in a lot of leaf spot and shoot blight diseases. These diseases, as well as branch cankers, may disfigure woody plants, but they seldom kill otherwise healthy plants. However, if leaf spots and blights were serious problems last year, infected plant material from last year may produce fungal fruiting structures this spring that release an abundance of inoculum. During wet springs, these spores infect young leaves and shoots. For high value plants where appearance is important, consider several applications of fungicides beginning as buds open if conditions are wet this spring. Alternatively, consider replacing plants with recurring leaf spots and blights with resistant varieties or other plant materials better adapted to the site.

In addition, if there was extensive branch dieback due to canker infections, this may be an indication that the tree or shrub is in a weakened condition. Useful management interventions consist of those activities that enhance the vitality of the woody plants. Suggestions include soil aeration, weekly soaking irrigations during dry periods, fertilization of poor soils, maintenance of a 2-3 inch layer of organic mulch over as much of the root zone as possible, as well as removal of dead branches and pruning to improve branch structure and air movement throughout the crown.

Ramorum Blight, also known as Sudden Oak Death (SOD). Since the early 1990’s, oaks and tanoaks were dying in the coastal counties of California. Since then, other types of plants have been found to be infected or associated with this disease, referred to as Sudden Oak Death, ramorum leaf blight or ramorum dieback, or by regulation as Phytophthora ramorum. The first positive identification of the disease was in 1995 on tanoak in Mill Valley (Marin County), California. Since that time, surveys confirmed Phytophthora ramorum on various native hosts and nursery plants in several locations in California, Oregon, Washington, and British Columbia. When nursery surveys find infected plants prompt quarantine and/or eradication activities ensue. Research conducted by the Agriculture Research Service, US Forest Service, universities, and others is under way to better identify hosts, improve methods of detection, and develop effective treatments. Currently, 84 plants are regulated, two of which at the genus level (Camellia and Rhododendron). There are no chemical treatments currently available to eliminate Phytophthora ramorum from infected plants.

Status of Phytophthora ramorum Monitoring Surveys. The 2005 National Nursery Survey involved 49 states and Puerto Rico. It reported that 3,790 nurseries have been visited and 68,275 samples collected. The surveys identified 56 positives sites in seven states. Overall, 99 positive sites have been reported this year. The breakdown by state is: CA (55), GA (4), LA (2), OR (20), TN (1), SC (1), and WA (16).

New Hosts Added. USDA PPQ issued a Federal Order on November 15 adding Abies concolor (white fir) and Viburnum opulus (= V. trilobum) (American cranberry viburnum) to the official USDA APHIS list of host and associated host plants.

Dan Gillman, Plant Pathologist, based in the UMass Extension Plant Diagnostic Lab at UMass, Amherst.

WEEDS

Two weeks ago, during the period of warm weather, I thought we might start seeing the growth of some winter annual weeds in ornamental beds; however, this recent cool snap has put a hold on any weed growth. Spring whitlowgrass or whitlowwort (Draba verna) in some warmer locations in the landscape may be near flowering. See Draba verna at our Online Weed Herbarium. Otherwise, all weeds are currently dormant.

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

TURFGRASS

Insects: No report: Visit the Landscape Message Archive for previous messages.

Weeds:

Some winter annual turf weeds may have grown during the previous warm weather, but currently there is nothing to report.

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

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

UMass Extension’s Turf Management Guide and IPM Facts: For more information about the pests mentioned in this message, you will need to refer to the following publications: the Professional Guide for IPM in Turf for Massachusetts, 2003-2004 edition and Turf IPM Facts . Call (413) 545-2717 to order these publications from the UMASS Outreach Bookstore.

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 Friday, March 17, 2006.

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 and made available to subscribers via electronic transmittal by Ellen Weeks.

DISCLAIMER. This message is intended for commercial use. UMASS Extension assumes no liability for recommendations. The use of trade names does not imply endorsement. Similarly, there may be other products you prefer to use.

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