Soybean aphids continue to be problematic across New York. Many
soybean fields have been over the economic threshold for soybean
aphids. Many of these fields have been sprayed with an insecticide.
Other soybean fields have seen a drop in aphid numbers over the
past week the result of activity by a variety of natural enemies
including aphid fungal diseases. See this weeks soybean aphid update
for more information. In my soybean sentinel plot in Washington
County we have discovered downy mildew and bacterial blight. Remember
no bacterial diseases can be treated with a fungicide.
Potato leafhopper (PLH) populations remain low across the state.
One exception was an over threshold field reported at the Cornell
Research Farm in Valatie. There were 100 PLHs in 3 samples (one
sample equals10 sweeps with the net) in 20 inch alfalfa.
Warmer weather and moist conditions have provided conditions
favorable for increasing house and stable fly populations on dairy
farms.
Weather Outlook August 6, 2009
Drew Montreu
NOAA Northeast Regional Climate Center
Temperatures during the past week were pretty close to normal,
with the entire state ending up within 3 degrees of average. Most
areas were on the cool side of that though. Precipitation was widely
variable, with none falling to the north of Buffalo, and over 4
inches falling over parts of the Catskills. In general, areas east
of I-81 had the best shot for over 2 of rain, while areas west of
there mostly got less than 2.
Base 50 Growing Degree Days accumulated 100 to 150 across most
of the state, with the lower values in the higher elevations, as
usual. Comparing seasonal values to last year, nearly everywhere
is 1 to 2 calendar weeks behind, and the majority of the area is
in the lower, 10 to 14 days behind range. Compared to normal, portions
of Western New York and the Tug Hill are 7 to 10 or more calendar
days behind, while a few areas in the Southern Tier and Hudson River
Valley are a couple days ahead. For the most part though, areas
are 3 to 7 days behind normal.
Another pretty decent week is upcoming, with high pressure keeping
control of the weather through most of Saturday. That means plenty
of sunshine for the next few days. Temperatures will be a bit cool,
with highs today, tomorrow and Saturday in the mid 70s. Lows should
be in the low to mid50s. There is a chance of an isolated shower
or storm on Saturday, but most areas should be dry. The chances
for a storm increase a bit on Sunday, but again, the majority of
places will see little if any rain, with highs in the low to mid
80s and lows near 60. Some heat will come in on Monday after a warm
front moves through in the morning, with morning lows in the upper
60s. Highs will reach into the upper 80s with some scattered thunderstorms
along this front and in the afternoon. A cold front will come through
on Tuesday, but not before highs reach into the mid to upper 80s
once again. Tuesday will have the best chance of rain as that front
goes through. There could be some showers on Wednesday as the front
slowly moves to the east, and highs will be near 80, with lows near
60. Over the next 5 days, most areas can expect to get between
one-quarter and three-quarters of an inch of rain. The 8 to 14 day
outlook is calling for slightly warmer than normal weather, accompanied
by more dry weather.
What pest problems to consider when planting winter wheat
Planting winter wheat is just around the corner. There are several
factors to consider when planting winter wheat. The first is to
never plant wheat in the same field two years in a row. By rotating
you reduce the risk of several diseases like eyespot foot rot, powdery
mildew, leaf rust, Stagonospora nodorum blotch, glume blotch
and more. The second item to consider is what winter wheat variety
to plant. Of course you will look at potential grain yield, grain
test weight and straw quality. It is also important to consider
resistance to diseases in the varieties you select. Diseases of
particular concern are wheat spindle streak mosaic virus, soil borne
mosaic virus, yellow dwarf virus (formally called barley yellow
dwarf virus), powdery mildew, leaf & stem rust and/or other disease
problems your farm has had in previous years. For a list of potential
wheat varieties consult your Cornell Guide for Integrated Field
Crop Management (available online at
www.fieldcrops.org). Next,
remember to plant AFTER the Hessian fly free date. By doing
so, not only are you avoiding infestations of Hessian fly but also
certain aphids that can transmit yellow dwarf virus. The following
figure shows the Hessian Fly Free Dates in NYS:
The use of certified wheat seed should be considered. When seed
is certified you can be confident of the quality and it is void
of diseases and weed seed. Next is to remember to always use a fungicide
seed treatment to protect the crop from certain seed and seedling
related diseases. Another core consideration is having a sound fertility
program. When a plant is healthy it can complete with weeds and
may tolerate more insect pest pressure and still maintain good yield.
Every year I see two kinds of beetles feeding on corn silks:
corn rootworm beetles and Japanese beetles. I have been asked
many times Does this feeding by beetles reduce pollination of corn
Generally, these beetles do not affect pollination of corn. Corn
rootworm beetles prefer to eat pollen. The corn plant can produce
enough pollen to pollinate the ear of corn and still have plenty
left over for the corn rootworm beetles.
In New York, the feeding of the adult beetles on silks can
occasionally be a problem. Clipping of the silks can prevent
pollination, resulting in poorly filled ears. If 10 or more adults
are found per plant at silking, less than 50 percent of corn silks
are brown, and silks <0.5 inch long, treatments to control adults
may be warranted, and pollination has not yet occurred, apply an
insecticide (see: www.fieldcrops.org,
Table 3.6.1).
The good thing is that even a damaged silk can still receive
pollen and willfertilize the ear. Reduced fertilization can only
occur when the silk isclipped to less than a inch long before
pollination.
Japanese beetles also like to feed on the silks of corn. I have
seen up to 8or 9 on one ear of corn. The thing with Japanese beetles
is that they prefer tofeed on browning silks. When the silk has
turned brown the ear of corn has alreadybeen pollinated. Japanese
beetles also clump in certain areas of the field.Many times this
is along edges and not the rest of the field.
Japanese Beetles on Feeding on Silks
Soybean Rust Update
Gary Bergstrom
Plant Pathology, Cornell University
Scouting has begun in sentinel plots in NYS in Cayuga, Jefferson,
Seneca, Washington and Wayne counties. This week low levels of bacterial
blight, bacterial pustule and Septoria brown spot were detected
in samples submitted from the NYS sentinel network. Nationally,
on August 4th, soybean rust was reported on soybean in a sentinel
plot in Baldwin County, Alabama. Additionally, recent detections
of soybean rust have been made on kudzu in Alabama and Florida.
Risk of spore transport to our region is low at this time. In 2009,
soybean rust has been reported in the U.S. in 34 counties in five
states (Alabama, Florida, Georgia, Louisiana and Texas). Updated
August 7, 2009
Soybean growth variable across state. Majority of fields currently
reporting late vegetative growth stages to early pod fill R3.
Observation and Outlook - Insect Last Modified:
08/06/09
Soybean aphid populations building with fields reaching threshold
being reported across NY. High populations reported in northern,
eastern and western regions. Populations of beneficial arthropods
including Coccinelids, syrphid flies, lacewings, parasitic wasps
and fungal pathogens have been increasing statewide. Some fields
in central NY that reported over threshold SBA numbers last week
have experienced a precipitous drop in SBA numbers to low 20's this
week resulting from impact of natural enemies including fungal disease
of SBA's.
Infested soybeans populated mostly by non-winged SBA's with some
winged forms present. Some fields with plants exhibiting stunting
and crinkling/puckering of leaves. Some fields treated with insecticide
earlier this season have again reached threshold for SBA, in some
cases only 2 - 3 weeks post treatment. Fields receiving application
of foliar insecticides will continue to require monitoring for possible
soybean aphid re-infestation later this season.
Observation and Outlook - Disease Last Modified:
N/A
Scouting and Management - Insect Last Modified:
08/06/09
SBA infestations variable on farms. Monitoring individual fields
recommended to provide the best information for management decisions.
Producers are encouraged to monitor soybean fields for this insect
pest, natural enemies and mid to late season soybean diseases. Follow
management guidelines as recommended in USDA protocols and Cornell
Recommendations for Soybean Integrated Field Crop Management.
General: * Emergency contact information ("911", local hospital,
Chem. Spill emergency contact, other) posted in central posting
area
* Maintain crop records by field, including variety, planting date,
pesticides used, nutrient inputs including manure, etc.
* Watch for any patches of herbicide resistant weeds, weed escapes
* Storage areas cleaned and ready to accept hay, wheat harvest
Corn: * Monitor fields for plant vigor, growth stage, mid to
late season pest issues (European corn borer, armyworm, foliar diseases,
nutritional deficiencies)
* Monitor for weeds, note presence of "who", "how many" and "where"
* Monitor reproductive stage corn fields for corn rootworm beetles
populations.
Small Grains:
* Evaluate crop for plant vigor, lodging, maturity / time till harvest
* Grain bins ready to accept upcoming harvest
Alfalfa & Hay: * Monitor alfalfa seedings for weeds, insects & diseases.
* Check regrowth of established alfalfa stands for potato leafhopper,
weed and disease problems.
* Storage areas cleaned and ready to accept incoming harvest
Soybeans: * Evaluate stand growth, development and condition
* Monitor fields for soybean aphid, foliar diseases, white mold,
natural enemies, defoliating insects, spider mites and weed escapes
Dairy Livestock Barn Fly Management: * Sanitation, sanitation, sanitation - clean animal resting
areas, feed troughs, minimize source of moist organic matter i.e.
fly breeding areas in barn and in adjacent animal loafing yard
* Check water sources, drainage, roof gutters for leaks and potential
overspill
* Continue fly monitoring: install "3X5" index card fly speck monitoring
cards through out barn
* Install/refresh/replenish as needed: fly tapes, insecticide baits,
natural enemies (parasitoids)
Dairy Livestock Pasture Fly Management: * Monitor animals for presence of pasture fly pests. Treatment
guidelines: Horn flies (50 per dairy animal side, 100 per side for
beef cattle), face flies(10 per animal face), stable flies (10 per
4 legs).
See IPM's Livestock page.
* Consider installing biting fly traps to reduce horse, deer
and stable fly populations.
Storage:* Check storage areas (bunk silos, etc.)
for readiness to accept upcoming wheat harvest
* Clean in and outside of storage bins and grain handling equipment
* Keep areas around storage bins and silos clean and mowed
* Check areas around storage bins and silos for vertebrate tunneling
* Check temperature of recently baled hay in hay mow
Equipment: * Note any repairs needed for recently used equipment:
tractors, tillage implements, planters, sprayers, etc. as they are
cleaned and serviced.
* Service hay harvesting equipment as needed.
* Calibrate manure spreaders - maintain records on amount spread
per field
PESTICIDE EMERGENCY NUMBERS Emergency responder information on pesticide spills and
accidents CHEMTREC: 800-424-9300
For pesticide information: National Pesticide Information Center:
800-858-7378
To Report Oil and Hazardous Material Spills in New York State: NYS
Department of Environmental Conservation Spill Response:_800-457-7362
(inNYS)_518-457-7362(outside NYS)
Poison Control Centers: Poison Control Centers nationwide: 800-222-1222.
If you are unable to reach a Poison Control Center or obtain the
information your doctor needs, the office of the NYS Pesticide Coordinator
at CornellUniversity,607-255-1866, may be able to assist you in
obtaining such information.
These pages are maintained by the New York State IPM Program, part of
Cornell Cooperative Extension.
All material is protected by Section 107 of the 1976 copyright law. Copyright
is held by Cornell University and the New York State IPM Program.
