Soybean aphid populations have dropped dramatically in many areas
of the state this week. Spider mites were observed in high numbers
in a drought stressed soybean field in western NY. White mold has
been observed in reproductive stage soybean fields with closing
foliar canopy.
Various foliar diseases, including gray leaf spot and northern
corn leaf blight, are evident in field corn across the state.
Flies affecting animals on pasture or around barns have increased.
Face flies and horn flies on pastured animals can become a major
problem as the summer continues. We have also heard that pink eye
has started to show up in a few herds of pastured cattle. Pink eye
is vectored by face flies. Horn flies and other biting flies like
stable, horse, and deerflies can also cause a lot of irritation
to cattle. During a pasture walk meeting this week Keith Waldron
discussed a few biting fly traps that can be used to help reduce
the breeding population of biting flies in a pasture setting. A
variety of traps are available commercially. The first trap discussed
is for tabanid flies (Horse and Deer flies) and Stable Flies
was a modified Manitoba trap commercially available as the Horse
Pal Fly Trap
Horse Pal Fly Trap
Flies Caught in the Horse Pal Trap in 1.5 hours.
A second biting fly trap demonstrated is made with alsynitea flexible fiberglass-like material is very effective for catching
stable flies. Alsynite fiberglass is specially made to reflect a
certain spectrum of light attractive to stable flies. Clear fly
paper is attached to the outside of the alsynite column and the
stable flies get stuck on the trap. The trap demonstrated was the
Olson Biting Fly trap.
Alsynite Biting Fly Trap
Certified seed and fungicide seed treatment are good insurance
for winter wheat
Soilborne fungal disease occurrence on roots, stems, and crowns
of winter wheat are generally not severe when wheat growers rotate
with non-cereal crops. However, low levels of soilborne and seedborne
fungal diseases can cause problems with stand establishment. A stand
that is not well established in the fall will have a harder time
making it through the winter, and may not be as quick to green up
in the spring.
Seedling disease threats can largely be prevented with the use
of fungicide-treated seed. These threats include the smut diseases
that maybe present on the surface of the seed or deep inside the
embryo of the seed. Also, several soil-dwelling disease agents can
cause plant roots and/or crowns to rot before the plant becomes
established. In addition, seed fungicide treatments can aid in the
suppression of early foliar diseases such as powdery mildew in the
fall.
Fungicide-treated seed is widely available commercially, or treatments
of fungicides can be made on-farm. The most effective treatments
combine a systemic fungicide and a protectant fungicide. For specific
reference to chemicals, please visit the
Cornell Guide for Integrated Field Crop Management.
Another key tactic for good stand establishment is to plant certified
seed. Use of certified seed assures a grower that seed meets high
state and national standards for purity, identity, and freedom from
noxious weed seeds and seedborne diseases.
It is important to monitor your fields for stalk rots as you
start thinking of your corn harvest. If you have an infection of
stalk rot it can cause the plant to die early losing grain or silage
yields. Stalk rots are caused by many different fungi that enter
the plant. They occur when the plant is under stress or when it
may be injured by insect pests, hail, deer and bird damages, drought
or soil saturation, lack of sunlight, extended cool weather, and
the lack of fertility. The following are symptoms of specific stalk
rots:
Anthracnose stalk rot symptoms may appear after tasselling as
vertical, tan to reddish brown, water-soaked lesions (streaks) in
the stalk rind. Lesions become large, dark brown to shiny black.
Fields with high amounts of anthracnose leaf blight (both diseases
have the same causal agent) should be checked for indications of
anthracnose stalk rot.
Diplodia stalk rot symptoms may appear as numerous black pycnidia
in the lower internodes of the stalk. The black dots are the size
of a pinhead or smaller. When conditions are wet a white mold may
develop on the stalk surface.
Fusarium stalk rot normally starts just after pollination and
symptoms appear later in the season. When you cut open the stalk,
the pith appears as a whitish to pink (salmon) color. There are
also distinctive brown streaks on the lower internodes.
The first symptom of
gibberella stalk rot is the onset of grayish-green color of
the leaves. The stalk will turn dark green to tan near the base
of the plant. The pith of the stalk becomes soft and will appear
as a red to pinkish color.
Pythium stalk rot normally appears as a decay of the first internode
above the soil. The pith will become soft, turn brown and appear
water-soaked. Many times the stalk can twist and/ or lodge. Even
though it may have lodged the plant will stay green for several
weeks because the vascular tissue is not destroyed.
If you discover certain stalk rot diseases make notes of the
hybrid, tillage methods, rotation history, and planting date. By
doing this you be able to avoid the disease occurrence in the future.
The following is the effectiveness of specific management practices
for stalk rots:
Corn Disease
(Stalk Rots)
Resistant Variety
Crop Rotation
Clean Plow
Down of Residue
Fungicides
Anthracnose
1
1
1
4
All Other
2
3
3
4
1= highly effective, 2= moderately effective, 3=slightly effective,
4= not effective, 5 = not usually economical,
Reference: Purdue University Field Crops Pest Management Manual
As with most diseases that attack corn, if you can reduce stress
on the plants you most likely can reduce the occurrence of certain
stalk rots. Having a sound fertility program based on soil testing
is important for keeping a corn plant healthy. Select a hybrid with
resistance to certain diseases and good standability that is adapted
to your region. Some of these stalk rots can produce mycotoxins
that can be toxic to livestock. You should consider having silage
tested for certain mycotoxins if you had fields with stalk rots
this season. For more information on corn diseases see our
Diseases of Corn Management Guide.
Scouting has begun in sentinel plots in NYS in Cayuga, Jefferson,
Seneca, Washington and Wayne counties. This week low levels of bacterial
blight 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
Crop Growth Stage Last Modified: 08/06/09 03:46
PM
Soybean growth variable across state. Majority of fields currently
reporting early pod fill R3.
Observation and Outlook - Insect Last Modified:08/20/09
Soybean aphid populations appear to be moderating
this week with many fields below threshold. Although field
by field variations still exist, in some cases SBA's have actually
been difficult to find in some areas where they were once very common.
Populations of beneficial arthropods including Coccinelids, syrphid
flies, lacewings, parasitic wasps and fungal pathogens have been
increasing statewide. Spider mites have been observed in fields
challenged by drought stress.
Scouting and Management - Insect Last Modified:08/20/09
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, spider mites 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,
pesticidesused, 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 pestissues (European corn borer, armyworm, foliar diseases,
nutritionaldeficiencies)
* Monitor for weeds, note presence of "who", "how many" and"where"
* Monitor reproductive stage corn fields for corn rootworm beetles
and otherinsect pests and diseases.
Alfalfa & Hay: * Monitor alfalfa seedings for weeds, insects & diseases.
* Check regrowth of established alfalfa stands for potato leafhopper,
weed anddisease 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,
naturalenemies, defoliating insects, spider mites, bean leaf beetles
and weed escapes
Dairy Livestock Barn Fly Management: * Sanitation, sanitation, sanitation - clean animal resting
areas, feedtroughs, minimize source of moist organic matter i.e.
fly breeding areas inbarn 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 speckmonitoring
cards through out barn
* Install/refresh/replenish as needed: fly tapes, insecticide baits,
naturalenemies (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), faceflies(10 per animal face), stable flies (10 per
4 legs).
See IPM'sLivestock page.
* Check temperature, moisture, pest status of recent binstored
small grains
* 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, tillageimplements, 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
accidentsCHEMTREC: 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
Departmentof Environmental Conservation Spill Response:_800-457-7362(inNYS)_518-457-7362(outside
NYS)
Poison Control Centers: Poison Control Centers nationwide: 800-222-1222.
If youare unable to reach a Poison Control Center or obtain the
information yourdoctor needs, the office of the NYS Pesticide Coordinator
atCornellUniversity,607-255-1866, may be able to assist you in obtaining
suchinformation.
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.
