Cornell Cooperative Extension of the
~~~Commercial Horticulture Electronic Newsletter~~~
Volume 9, Issue 8
August 27, 2009
Participating Counties: Orange * Dutchess * Putnam *
Editor: Rosemarie S. Baglia
www.cce.cornell.edu
In this Issue:
Westchester County Seasonal Update – August 2009
As of August 27, rainfall levels for the month of August at Westchester
County Airport have indicated that we have received somewhere in the vicinity
of 1”-2” above normal totals. Also, GDD amounts have totaled 2211 (over
100 GDD less than this time last year)….as with July, the numbers tell us that
August was also cooler and wetter than normal.
Calls to our diagnostic lab have continued to involve questions about hard to
manage weeds in lawns such as Japanese stiltgrass and
Nutsedge. The calls about White grubs that we
normally receive this time of year are still relatively non-existent, although
one golf course has reported some localized activity. Additionally, as
temperatures “heated up” (relatively speaking, of course) over the past month,
we started observing and getting calls about summer turf disease including
Brown patch, Dollar spot, Pythium, and Take-all patch
browning out bentgrass populations in lawns.
As one would expect with all the moisture we’ve been receiving this summer,
diseases have continued to be prolific on ornamentals. Black leaf spot on
elm, Anthracnose on many broadleaved species, and Guignardia
leaf blotch on horsechestnut have all been readily
noted. Canavirgella leaf blight has also been
widely observed on White pine trees.
Lastly, we recently had a conversation with a commercial arborist about the
phenomena known as summer (sometimes referred to as “sudden”) limb
drop. He reported this occurrence taking place on two different
instances on trees on residential properties. Researchers seem to
continue to debate the actual reasons for the occurrence of summer limb drop in
trees, however there seems to be some agreement that it may be related to an
imbalance in the rate of moisture uptake and transpiration. To read more,
open the following link featuring an article from University of California
Extension Coordinator Pamela Geisel: http://cefresno.ucdavis.edu/files/6758.pdf
Written by Rick Harper & Jerry Giordano, Cornell Cooperative
Extension of Westchester County
Emerald Ash Borer Update
Since the first detection of emerald ash borer (EAB, Agrilus
planipennis Fairmaire)
in Randolph, NY, on June 15, 2009, New York State and federal partners have
identified a 10-acre infestation area that included 39 trees, all of which have
since been cut and chipped. Trapping efforts are currently underway to
determine if the infestation has expanded beyond this initial detection site.
The natural spread of EAB is slow, often less than 5 miles per year, but may
increase 6 fold when human-assisted. The long distance movement of firewood and
infested nursery stock is primarily responsible for the spread of EAB to new
locales.
To limit the potential introduction of EAB to other areas of the state and
protect New York’s more than 900 million ash trees, the New York State
Department of Environmental Conservation (DEC) and the Department of
Agriculture and Markets (DAM) have implemented a quarantine for Chautauqua and
Cattaraugus Counties.
The complete article and additional resources can be found at http://nyis.info/insects/EmeraldAshBorer.aspx
Submitted by Teresa Rusinek Cornell Cooperative
Extension of Ulster County
Be on the Lookout for White Rust in Chrysanthemums
White Rust has been confirmed at a nursery in Connecticut and suspect
plants have been reported in Massachusetts and Pennsylvania. The article
below was written by Brian Eshenaur of NYS IPM.
As fall approaches and chrysanthemum crops mature, growers should be aware of a
disease that can devastate a crop: chrysanthemum white rust caused by the
fungus Puccinia horiana.
This disease is not known to overwinter in the
It is important to scout your crop and also check mums near the greenhouse in
the landscape including Montauk daisy. Look for any small yellow spots –
especially those less than ¼” in diameter. The best place to look for the spots
is on the upper surfaces of the young leaves and flower bracts. A
characteristic feature that helps separate these spots from other spots is the
tiny brown speck in the center. Raised tan to pink colored pustules develop on the opposite side of the leaf, under the yellow
spots. These pustules, from which spores are released, fade to white with age –
hence the name white rust.
To help prevent this disease from occurring at your operation, carefully
inspect incoming mums. Imported cut flowers should never be handled in or near
a mum growing facilitya particular challenge for
greenhouse/florist operations. Cool humid conditions favor this disease (temp.
range from 63 – 75 F).
Since chrysanthemum white rust is a federal quarantine pest, growers are
obligated to report it. If you are not sure if you have white rust, contact
your extension office or NY Ag and Markets to get a confirmation and required
control information.
Submitted by Teresa Rusinek, Cornell Cooperative
Extension of Ulster County
Scientists Identify Weevil as Biocontrol for Garlic
Mustard
By Stephanie Yao, USDA-ARS Staff Writer, July 2009
A promising biocontrol agent for garlic mustard, one
of the most problematic invaders of temperate forests in North America, has
been identified by Agricultural Research Service (ARS) scientists and cooperators.
Garlic mustard, Alliaria petiolata, got its name because its leaves, when
crushed, smell like garlic. According to legend, it was brought here from
Since then, this invasive weed has spread to 34
Ecologist Adam Davis, with the ARS Invasive Weed Management Research Unit in
CABI scientists also found four Ceutorhynchus
weevils as potential biocontrol agents for garlic
mustard.
The tiny C. scrobicollis only eats garlic
mustard. It feeds on the weeds root crown, the area where nutrients are stored.
This stops the flow of nutrients and water from the roots to the rest of the
plant. The weevil also damages the meristem, the area
where new growth takes place. As a result, garlic mustard produces fewer seeds
or, in areas with high weevil populations, dies prematurely without producing
any seeds.
C. scrobicollis is currently awaiting release
at the
Submitted by Rick Harper, Cornell Cooperative Extension of Westchester
County
Trap Would Help Keep Stink Bugs Outdoors
By Dennis O'Brien, USDA-ARS Staff Writer, July 2009
A trap to keep stinks bugs from Asia out of peoples homes is being developed by
Agricultural Research Service (ARS) scientists.
The brown marmorated stink bug, Halyomorpha
halys, has expanded its range to
The bugs impact on crops remains to be seen, but the
biggest problem so far has been that it looks for warm wintering sites and
makes its way indoors when the weather turns cool each fall. These bugs don’t
harm humans, but if they’re squashed or pulled into a vacuum cleaner, they
smell.
Entomologist Jeffrey Aldrich and chemist Ashot Khrimian, at the ARS Invasive Insect Biocontrol
and Behavior Laboratory in
Aldrichs experimental traps show that stink bugs
increased from barely detectable levels in 2004 to numbers that now surpass
those of the native green stink bug.
Aldrich and Khrimian are searching for an attractant
pheromone to synthesize and use in a trap. In
Khrimian synthesized the compound and with it
produced experimental dispensers used in traps to monitor the bug’s population.
But synthesizing the bugs own pheromones would likely make for a more effective
trap than one based on pheromones from another stink bug.
Aldrich is raising H. halys in his lab,
inserting them into specially vented tubes, and using gas chromatography to
look for pheromones among their emissions. To read more, visit: http://www.ars.usda.gov/is/pr/2009/090727.htm
Submitted by Rick Harper, Cornell Cooperative Extension of Westchester
County
"Professional Strength" Misleading
EPA Letter Reminds Pesticide Companies of Federal Pesticide Label Regulations
and the Agency's Position on Use of Terms Like "Professional
Strength"
EPA has posted a recent letter regarding permissible product names and
advertising for pesticide products. The goal of this letter is to remind
pesticide producers and distributors of federal pesticide label regulations and
the Agency's process for addressing misbranded products, such as those with
false and misleading statements.
The letter includes examples of statements that are considered false or
misleading according to federal regulations (40 CFR part
156.10(a) (5)). EPA further explains why it finds the use of the term
"Professional" in product names, labeling and marketing to be false
or misleading under the Federal Insecticide, Fungicide, and Rodenticide
Act and therefore unacceptable. Pesticides cannot be sold, distributed,
and promoted with inappropriate words such as "Professional" and
"Professional Grade" in product names and advertising. This
applies to distributor products as well as the basic registered product.
When distributor products contain claims that have not been accepted for the
basic registration, the label is in violation of 40 CFR part
152.132(d). Both the distributor and the basic registrant are liable for
violations pertaining to the distributor product. The letter is available
on EPA's Web site at www.epa.gov/pesticides/regulating/labels/product-labels.htm.
EPA's Office of Pesticide Programs (OPP) provides information on its Web site
about the regulations that govern labels and advertising, along with tools for
understanding how the Agency reviews pesticide labels (
www.epa.gov/pesticides/regulating/labels/label_review.htm).
Submitted by Jennifer J. Stengle, Cornell
Cooperative Extension of Putnam County
Creating the Ultimate Drought-Resistant Lawn/Pasture Grass
By Don Comis, USDA-ARS Staff Writer, August 2009
ARS geneticist Jason Goldman at the agency’s Southern Plains Range Research
Station in
Goldman’s goal is a Kentucky bluegrass-like lawn or pasture grass that is
highly tolerant to drought. The research is part of the laboratory’s program
for breeding perennial cool-season forage grasses for the southern
Goldman’s goal is to combine them into one variety with a broader geographic
range than Kentucky bluegrass, while retaining Kentucky bluegrass good
qualities. The hybrid must also retain Kentucky bluegrass ability to produce
seed that breeds true, ensuring identical progeny.
Goldman plans further tests to cross
This research was published in the journal Plant Breeding.
ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.
To learn more, visit: http://www.ars.usda.gov/is/pr/2009/090817.htm
Submitted by Rick Harper, Cornell Cooperative Extension of Westchester
County
Turf Nematode Update
Many golf course managers are encountering high populations of nematodes this
summer. For a primer on nematodes that impact turf, including sampling
information, visit www.umassturf.org/mangement_updates/management_updates.html
Submitted by: M. Bess Dicklow, Extension Plant
Pathologist, UMass Extension Plant Diagnostic Lab. (The UMass Extension
Turf Program - www.umassturf.org)
Professional
Horticulture Programs of Interest
Certified Landscape Technician Training
Contact: NYSTLA at 914-993-9455 or visit www.nystla.com.
An optional national testing program to recognize proficiency
of qualified landscape professionals.
Certified Nursery Professional Training Program
Contact: In Dutchess, Putnam & Westchester:
Scott Olivieri, 914-682-4224;
In Orange, Rockland & Ulster: Mark Masseo
845-658-9148
By passing this exam you can earn the title Certified Nursery Professional
(CNP). Contact your New York State Nursery and Landscape Association,
listed above, for more details.
Cornell Cooperative Extension County Commercial Horticulture Educators
Dutchess: Stephanie Mallozzi, sdm10@cornell.edu, 845-677-8223 x 104
Orange: Rosemarie Baglia, rsb22@cornell.edu,
845-344-1234
Putnam: Diane Olsen, dko3@cornell.edu, or Jennifer Stengle,
jjs95@cornell.edu, 845-278-6738
Rockland: Donna Cooke, dmc72@cornell.edu, or Paul Trader,
pwt2@cornell.edu, 845-429-7085
Ulster: Teresa Rusinek, tr28@cornell.edu,
845-340-3990
Westchester: Rick Harper, rwh26@cornell.edu, 914-946-3005
Sullivan: Marianna Quartararo,
mdq2@cornell.edu, 845-292-6180 x 112
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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