Weekly Field Crops Pest Report 2009

View from the Field

Ken Wise
NYS IPM

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While infestations of soybean aphid have been decreasing you can still find them in fields. While scouting a soybean field this week I counted 0 to 240 aphids/plant. There was an average of 60 aphids per plant. Very soon you should start to see winged forms of the aphid. They will fly from fields to buckthorn tree/shrubs. They will then lay eggs on the plant where they will overwinter.

White mold on soybeans has been found in a few fields in Western New York. For more information on white mold please see the article below.

Keith Waldron reports that Western Bean Cutworm (WBC) moths have been caught in WNY. Pheromone traps set out by Mycogen Seeds and the WNY CMA have caught Western Bean Cutworm moths in Genesee, Livingston, Ontario, Wyoming, and Yates counties. Moths were caught between mid July and early August. This is the first record of Western Bean Cutworm in NY. WBC's were also detected for the first time this summer by entomologists in Ontario and Pennsylvania. WBC were first detected in Ohio in 2006.

Weather Outlook

Jessica Rennells
NOAA Northeast Regional Climate Center, Cornell University

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Temperatures during the last week were above normal for the entire state, most of the state being 3 to 6 degrees above normal.  Precipitation ranged from .01 to 3inches.  The Great Lakes, Central Lakes, Mohawk Valley, St. Lawrence Valley, and part of the Eastern Plateau had0.5 to 1 inch while areas in the Catskills and northern Hudson Valley had 2-3inches.  The rest of the state was in the 1-2 inch range.

Base 50 Growing Degree Days ranged from 100 to 200, but most of the state was between 125 and 150. The entire state is behind last year.  Western NY, St. Lawrence Valley, the Northern Plateau and southern Hudson Valley are 1-2 weeks behind last year.  The rest of the state is up to 1 week behind last year.  The departure from normal varies more, ranging from 2 weeks behind to 2 weeks ahead of normal.  Part of the Western Plateau, western St. Lawrence Valley, and western Northern Plateau are 10 to 14days behind normal.  The southern tier, northern Champlain Valley, Mohawk Valley, part of the Eastern Plateau, and central Hudson Valley are mostly 0 to 10 days ahead of normal.  There are areas within those regions that are 10 to 14 days ahead of normal. The remaining areas of the state are 0 to 7 days behind normal.  

Cooler temperatures and rain are in the forecast for the next week.  A cold front continuing to move through the state will leave temperatures in the upper 60's and low 70's for today and Friday. Lows tonight will be cold in the 40's.  Friday night will be in the 50's.  Saturday's highs will be in the 70's and low temperatures in the 50's and some low 60's with precipitation likely.  Sunday low pressure will still control the area as another cold front moves through. Temperatures will be in the low 70's with lows in the low to mid 60's and more precipitation likely. Monday's highs will be in the upper 60's and low 70's and low temperatures in the upper 50's and low 60's with a chance of scattered showers.  A high pressure system will allow sunny skies Tuesday and Wednesday.  Both days will have highs in the low 70's and lows in the low to mid 50's.   The 5 day precipitation totals range from 1 inch over western NY to 3 inches over eastern NY.  The 8-14 day outlook shows above normal temperatures and below normal precipitation.

White Mold in Soybeans

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Highly productive, dense stands of soybeans favor white mold development. The fungus survives from year to year in the soil as hard black pellets called sclerotia. Sclerotia of white mold must be present to cause the disease, though a small number of sclerotia on the soil surface can lead to significant outbreaks if wet, cool conditions are present while plants are flowering. Under these favorable conditions, sclerotia will germinate and mushroom-like structures (apothecia) will form. The apothecia produce ascospores which spread by wind and splashing rain. Ascopsores require a nutrient source to grow, and soybean flowers serve as ideal locations. The fungus colonizes dead flowers and the characteristic thick white moldy covering on stems and pods develops (see photo below). Mixed in with the white mold on stems are the black sclerotia. Plants may wilt and die as a result of infection. If white mold infection occurs late in the season, yield loss will not be as severe. Temperatures over90 degrees will typically stop disease development. During harvest, the sclerotia on stems and pods may end up in the soil or residue, or may stay with harvested seed.  Fields where white mold has occurred in the recent past are where it will most likely occur, so these are the fields to scout the most closely for disease development.

The following photo shows the white mold infection on a plant that is starting to wilt.

Photo taken by Mike Stanyard

A key to white mold management is to find strategies to prevent the build-up of the pathogen in a field. Rotation to crops other than soybean for at least 1year (ideally 2 or more years) is recommended. Additionally, weed management practices that reduce weeds that serve as alternate host for white mold (for example lambs quarters and pigweed) will help to decrease build-up of the pathogen. It is also essential to avoid the planting of contaminated or infected seed, and to avoid the movement of infected soil with equipment. A strategy for preventing movement of infected soil is to harvest fields infected with white mold last. Varieties of soybeans that are tolerant or moderately resistant to white mold should be selected. Yield protection by spraying fungicides has not been documented in New York.

Western Bean Cutworm

Keith Waldron
NYS IPM

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Western Bean Cutworm moths were detected in pheromone traps earlier this month in western NY. Western Bean Cutworm (WBC) is a pest of corn (field, sweet and seed) as well as dry beans (not soybeans) and to a lesser extent tomatoes and nightshade. Unlike other cutworms, this pest prefers to feed on the fruit of the plant, ie, corn ears and bean pods.

The number of moths detected in NY were low indicating presence, although significant damage from larval feeding is not expected this season. Still, it is worth scouting fields for signs of WBC damage when monitoring for other pests such as corn rootworm and stalk rot diseases in corn and dry bean pest issues.

The western bean cutworm is native to North America. It was first discovered in Arizona in the 1880s. Prior to 2000, economic damage was confined to the western Corn Belt states, and several mountain states where dry beans also were grown. Beginning in 2000, economic damage was found in Iowa and Minnesota. It was collected for the first time in Illinois and Missouri in 2004, and in Indiana, Michigan and Ohio in 2006. (Source: Western Bean Cutworm Pest Alerts from the IPM Center North Central Region)

Adult WBC moths are easy to identify from other corn pests. Each wing of the moth has a white band running along the edge or margin of the wing and has a spot or "moon' and boomerang-like mark. WBC larvae can cause extensive damage to corn and dry beans. Several factsheets are available with photographs and descriptions of the moth and larval feeding damage caused by these insects.

We would be interested in any observations from the field regarding detection and potential damage caused by this insect.

Western Bean Cutworm Scouting Videos:

Video for Scoutingfor Western Bean Cutworm Damage in Northwest Indiana (Purdue)

Western Bean Cutworm- A Pest of Field and Sweet Corn (U Wisc.)

For more information see:

North Central IPM Center Pest Alert: Western Bean Cutworm

and A New Pest Heading this Way - Western Bean Cutworm

Stop! Check for Corn Ear Rot

Ken Wise
NYS IPM

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Are you ready with the chopper or combine? STOP; check for corn ear rots first! Some kinds of fungi can create mycotoxins that are toxic to livestock. Taking a few minutes to check a field for certain ear rots can help you determine if you want to feed your field of corn to livestock. Pull back the husks on several plants and look for the presence mold growing on the ear of corn. The following are specific symptoms of certain ear rot diseases that can be found in NYS:

Fusarium Ear Rot appears as a white-to-pink or salmon-colored mold. This mold can begin with bird, deer or insect-damaged kernels. Fusarium ear rot may contain fumonisins which are mycotoxins that can be toxic to livestock.

Gibberella Ear Rot symptoms are pink to reddish colored mold. This disease starts near the tip of the ear and progresses down toward base of the ear. Gibberella can produce vomitoxin and zearalenone which is toxic to many kinds of livestock.

Diplodia Ear Rot symptoms appear as a thick white mold that usually starts near the base of the ear. This disease can also appear on the plant as raised black fruiting bodies on moldy husks or kernels. Diplodia does not produce any known toxins.

Cladosporium Ear and Kernel Rot symptoms appear as greenish black, blotched or streaked kernels scattered over the ear. This disease can also infect kernels that have been damaged by insects, birds, deer, hail, or frost. The disease can progress after the grain is harvested and stored.

Penicillium ear rot or blue eye symptoms range from a powder-like green or blue-green mold that is on and between the kernels and normally on the tip of the ear. If this disease progresses in storage it is referred to as blue eye because the germ is a bluish-green color. Penicillium ear rot can produce a mycotoxin called "ochratoxin".

If you discover certain ear rot diseases make notes of the hybrid, tillage methods, rotation history, and planting date. By doing this you can avoid the disease occurrence in the future. The following is the effectiveness of specific management practices for corn ear rots:

1= highly effective, 2= moderately effective, 3=slightly effective, 4= not effective, 5 = not usually economical,

Reference: Purdue University Field Crops Pest Management Manual

While there isn't any practical solution for coping with ear rots this late in the current season proper fertilization, timely weed control and reductions in insect pest pressure can help reduce risk of disease. For example: European corn borer (ECB) resistant Bt corn is at lower risk for injury by this insect. Lower risk means fewer ECB tunnels into stalks and less potential for fungi to infect through wounds and cause stalk rot. Also avoid continuous planting of corn under conservation tillage where stalk rot can be prevalent. If you are harvesting corn grain make sure you clean the grain bins. Keeping the proper temperature, moisture content and good aeration in the grain bin can reduce storage molds from developing. It is important to have regular inspections of the stored grain. This is essential to minimize risk of developing insect and mold associated storage problems. Harvest silage at recommended maturity and moisture level, and pack silage tightly and exclude air rapidly. Consider using organic acid preservatives if you can't exclude air or reduce moisture. If you had a lot of stalk rot and were growing for grain consider chopping earlier for silage to minimize lodging and combine losses. There are kits you can purchase to test your corn for different toxins on your own farm. The following are places where you can also test your corn:

Dairy One Forage Lab in Ithaca: For more information, call the lab at 1-800-496-3344 extension 172.

The Cornell College of Veterinary Medicine's Nutritional and Environmental Analytical Services Lab: More information is available on the website or from lab manager Joe Hillebrandt at 607-257-2345

Winter Wheat, Aphids and Yellow Dwarf Virus

Ken Wise
NYS IPM

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Barley yellow dwarf virus, also know as yellow dwarf virus (YDV) in wheat is a serous disease across the country. This disease is transmitted by several species of aphids that infest wheat. When infected aphids feed on the plants they infect the wheat with the virus. Winter wheat that is infected in the fall does not show symptoms. Symptoms start to appear mid-spring as yellowing of leaves. One management strategy is to plant wheat after the Hessian fly free date in your region. This can limit the number of aphids entering the fall seeded winter wheat fields. Another management option is to plant a wheat variety that is resistant to YDV.

Storing Corn or Soybeans? Remember Stored Grains Pests!

Ken Wise
NYS IPM

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Have plans to store your soybean and grain corn harvest on farm* If so, now is the time to start CLEANING your storage bins. Sanitation is the key to keeping insect pests out of your stored grains. Soybean and Corn harvest is not as far off as you may think so knowing what you need to do is important. The following is a step by step method for IPM in stored grain:

1.   Clean grain handing equipment (augers, combines, wagons, scoops, and trucks).

2.   Clean inside the grain bin (remember to clean under the false floor). Mice, moths, weevils and much more can survive under the false floor.

3.   Clean around the outside of the grain bin. Remove all weeds, spilled grain and debris 6 to 10 feet from around the grain bin. This will remove all habitats that can support a grain bin pest problem.

4.   Seal all cracks and crevices. Cracks are prime locations forinsects to enter grain bins.

5.   Cover fans when they are not being used. Insects can enter the grain bin this way also.

6.   Use a registered sanitizing insecticide spray in and around the structure after cleaning.

7.   Never store new grain with old grain.

8.   Dry the grain bin before adding new grain. Insect pests need moisture to survive.

9.   Level the surface after filling the grain bin. Moisture accumulates in a grain peak.   Microbial activity in the wet area will heat up and attract secondary insect pests.

10. Do not fill grain bin all the way to the top. Leave a few feet for aeration.

11. Aerate the grain to at least the ambient temperature. The hotter the grain gets the faster insect   pests can develop. Stored grain insect pests development slows when the temperature falls below 50⁰F.

12. Monitor grain for insect pests every 20 days from spring till fall and every 30 days in the winter.  

13. If you discover an infestation of insect pests you may consider an insecticide application. Select   a NYS registered product for your stored grain. READ THE LABEL.

14. Keep areas around grain bins mowed to limit rodent hiding places.

Common Insect Pest of Stored Grain:
*Granary weevil
*Saw tooth grain beetle
*Red flower beetle
*Larger cabinet beetle
*Lesser grain borer
*Rice weevil
*Indian-meal moth
*Flat grain beetle
*Angoumois grain moth
*Confused flower beetle

(See: Maintaining Quality in On-Farm Stored Grain, IPM in Kentucky Farm Stored Grain and Improve Stored Grain Through IPM from Oklahoma State)

Soybean Rust Update

Gary Bergstrom
Plant Pathology, Cornell University

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United States Soybean Rust Commentary (updated: 08/25/09)

On August 25th, soybean rust was detected at low levels in a commercial soybean field in Sumter County, Alabama. On August 23rd, soybean rust was reported at low levels in commercial soybean fields in Calhoun, Coahoma, Quitman and Tallahatchie counties in Mississippi. On August 22nd, soybean rust was reported on kudzu in Bay County, Florida. In 2009, soybean rust has been found in seven states and 66 counties in United States, and in two states and five municipalities in Mexico.

NY State Soybean Rust Hotline: 607-255-7850

NYS Soybean Rust Website

USDA Soybean Rust Website

Soybean Aphid Update

Keith Waldron
NYS IPM

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Crop Growth Stage

Soybean growth variable across state. Majority of fields currently reporting late vegetative growth stages to mid pod fill R5.

Observation and Outlook

Soybean aphid (SBA) populations have moderated with many fields below threshold. Although field by field variations still exist, SBA's are becoming  more 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 reported statewide.

Scouting and Management

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.

For more information see the USDA Public PIPE website

Clipboard Checklist

Keith Waldron
NYS IPM

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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, late season pest issues (European corn borer, armyworm, foliar diseases, nutritional deficiencies, vertebrate damage)
* Monitor for weeds, note presence of "who", "how many" and" where"
* Monitor reproductive stage corn fields for corn rootworm beetles and other insect pests and diseases
* Prepare storage areas to accept upcoming silage 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, naturalenemies, defoliating insects, spider mites, bean leaf beetles and weed escapes

Dairy Livestock Barn Fly Management:
* Sanitation, sanitation, sanitation - clean animal resting areas, feed throughs, 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), faceflies(10 per animal face), stable flies (10 per 4 legs). See IPM's Livestock page.

* Consider installing biting fly traps to reduce horse, deerand stable fly populations.

Storage:

* Check temperature, moisture, pest status of recent bin stored 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, 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

• 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 Cornell University, 607-255-1866, may be able to assist you in obtaining such information.

Contact Information

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Keith Waldron: NYS Livestock and Field Crops IPM Coordinator
Phone: (315) 787 - 2432
Fax: (315) 787-2360
Email: jkw5@cornell.edu

Ken Wise: Eastern NYS IPM Area Educator: Field Crops and Livestock
Phone: (518) 434-1690
Fax: (518) 426-3316
Email: klw24@cornell.edu