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Weekly Field Crops Pest Report 2007

September 17, 2007                Volume 6 Number 17

1. View from the Field

2. Certified seed and fungicide seed treatment are good insurance for winter wheat

3. Dry Conditions in Western NY: Impacts on Forages next year and on grain corn now

4. Storing Corn or Soybeans? Remember Stored Grains Pests!

5. Fall IPM Alfalfa Assessment

6. Alfalfa Snout Beetle in Fall Alfalfa

7. Soybean Rust Update

8. Soybean Aphid Update

9. Clipboard Checklist

10. Contact Information

View from the Field

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This issue will be the last report for the 2007 growing season. Since this is our final weekly report for this year we have added a few more articles highlighting IPM in the fall than usual. We have enjoyed creating this weekly publication and hope you have found it informative, useful and timely. Thanks to the many Extension Educators, field scouts, and industry personnel who shared their field observations and other information this season. The importance of these inputs cannot be over estimated for their enhancements to the timely value of the report.

We will soon be sending our subscribers a survey via email to solicit feedback regarding perspectives on the usefulness of this publication to your efforts and suggestions for how to improve the report next season. We hope you will take time to complete and return the survey. We take your comments and suggestions seriously and have incorporated many of your suggestions to improve the publication over the years. Thank you for your interest. See you next year!

Certified seed and fungicide seed treatment are good insurance for winter wheat

Julie Dennis

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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 may be 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 online at: Table 5.7.1. Seed treatment for small grains

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.

Dry Conditions in Western NY: Impacts on Forages next year and on grain corn now

Julie Dennis

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The extended dry periods experienced in many areas of Western NY this season may have contributed to damage in perennial forage crops.  Diseases and insects that attack roots and vascular systems have a greater impact on plants experiencing stress from lack of water. Clover root curculio and alfalfa snout beetle larval damage may be more pronounced after a dry spell, and vascular diseases like Verticillium wilt, root rots like Phytopthora, and crown diseases like Fusarium crown rot will have more impact.   Fields where very dry conditions were seen this year will need careful evaluation in the spring to determine if plants withstood the combination of stresses in ’07.

More immediate effects of dry conditions are already being revealed to us in the form of thin, brittle stalks in field grain corn.  Gary Bergstrom described the situation as a “source / sink” issue. Plants are working hard to send photosynthates to the developing kernels. Under dry conditions, less internally produced plant food, or photosynthate, is made.  Kernels win over stalks as the place where plants send their manufactured food. Stalks lose out and become weakened and at risk for stalk rots such as Diplodia, Anthracnose and Fusarium. We can only hope for ideal fall weather so that harvest can happen on time!

Storing Corn or Soybeans? Remember Stored Grains Pests!

Ken Wise

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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 for insects 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 500 F.

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: IPM in Kentucky Farm Stored Grain,  IPM Tactics for On-Farm Stored Grain (pdf file), and Improve Stored Grain Through IPM from Oklahoma State)

Fall IPM Alfalfa Assessment

Ken Wise

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Fall stand counts are an indication of the health of your alfalfa crop. There are a number of pests and crop management issues that can reduce a stand count in alfalfa. The following are guidelines for stand counts in NYS:


Crowns per square foot

Harvest Year

Optimum Stand

Adequate Stand

New Spring Seeding



1st hay year



2nd hay year



3rd and older



Fall scouting before the first hard frost can also reveal pest problems. If you find yellow to brown plants it may indicate one of several different disease problems. These could range from disease problems such as verticillum wilt, leaf spots, fusarium wilt, anthracnose and more. An inspection of the root system can also indicate disease problems. Yellow, reddish-brown to black discolored or damaged roots may indicate presence of phytopthora root rot or verticillium wilt. Premature senescence of alfalfa stands may indicate stress damage by alfalfa snout beetle larvae in those counties with confirmed infestations.

Alfalfa Snout Beetle in Fall Alfalfa

Keith Waldron

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Short, chlorotic alfalfa? Alfalfa stands showing signs of premature senescence?

Do you grow alfalfa in Oswego, Jefferson, Cayuga, Wayne, Lewis, St. Lawrence, Clinton, Essex or Franklin Counties?

If your farm is located in one of the above NY counties where ASB has been confirmed… watch your alfalfa fields for signs of stress. Fall is when fields can begin to show symptoms of ASB larval feeding damage. Alfalfa snout beetles (ASB) are root-feeding weevils.  The vast majority of ASB impacts come from direct root loss and plant death caused by ASB larval feeding. ASB feeding damage may be suspect if one detects alfalfa fields with short, chlorotic, or otherwise weakened plants or large areas within fields void of any alfalfa.

In North America these insects are only found only in the nine northern New York counties listed above and in portions of southern Ontario, Canada.  The native home of snout beetle is Europe where it can be found from Italy to England and Poland.

Alfalfa snout beetle larvae are legless, white, and 1/2 inch long. ASB larvae are found shallow in the soil when very small but move deep in the soil during mid July to late August (18-24 inches). In September the large larvae move back up to the top 8 " and do most of the tap root severing in September and October.  After development is completed, they then move deep in the soil to overwinter. Larvae move deep in the soil in the fall after feeding (18-24") and remain there for the next 18 months.  Midway through the summer they pupate but remain deep in the soil until the following spring.

If you grow alfalfa in one of the counties mentioned and suspect ASB injury, dig up a few plants showing symptoms getting as much of the root system as possible. Look for damaged, girdled roots and presence of ASB larvae.

ASB damage in the spring looks similar to winter killed alfalfa with plants failing to "green up".

Plant breeding and biological control research is underway at Cornell to develop options to mitigate ASB injury. But for now the best option for managing this important pest is a three year crop rotation with a row crop.

Soybean Rust Update

Gary Bergstrom
Cornell University Plant Pathology

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New York State Soybean Rust Information Center

Weekly scouting continues to be conducted in twenty New York State sentinel plots located in the following counties: Cayuga, Chautauqua, Chemung, Chenango, Columbia, Cortland, Jefferson, Monroe, Oneida, Onondaga, Ontario, Oswego, Otsego, St. Lawrence, Seneca, Steuben, Suffolk, Wayne, and Wyoming. Plant stages reported this week range from R-5 to R-7. Low levels of Bacterial Pustule and Downy Mildew have been detected this week in many of the NYS sentinel plots. Additionally, moderate levels of Septoria Brown Spot have been observed. Please view the 2007 NY State Soybean Rust Sentinel Plot Reports for specific county information.

Recent detections of soybean rust in the U.S. were made in a commercial soybean field in west-central Alabama, on soybean in Washington County, Arkansas and in a soybean research plot in Cook County, Georgia. To date this year, rust has been reported in 25 counties in Texas (24 soybeans), ten counties in Alabama (six soybean), five counties in Arkansas (all soybean), thirteen counties in Florida (five soybean), eight counties in Georgia (four soybean), fourteen parishes in Louisiana (thirteen soybean), six counties in Mississippi (five soybean), and six counties in Oklahoma (all soybean). There also has been one account of soybean rust earlier this year in Mexico in the state of Veracruz on yam bean (Pachyrhizus erosus). (Updated September 7, 2007 )

Soybean Aphid Update

Keith Waldron

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Soybean aphid populations have crashed in the past two weeks indicating the end of our NY soybean aphid season risk. In addition, soybean fields have generally matured to mid to late pod filling stages where economic risk from aphid injury has not been shown. For more information on soybean rust / soybean aphid in NY and the US see:

Clipboard Checklist

Keith Waldron

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* Maintain crop records by field, including crop condition, inputs, observations, issues, concerns, etc.
* Prepare bunkers, silos for incoming silage.
* Mow around storage bins, barn and farm facilities

Alfalfa & Hay:
* Monitor fields for weeds and diseases record information on type and location, note stand condition for future cropping / rotation decisions.

Small Grains:
* Check grain storage bins for temp, moisture, air flow, drying conditions.
* Prepare for planting winter wheat after Hessian Fly-free date.

Field Corn:
* Harvest corn silage at 65 to 68% moisture and high moisture shelled at 25 to 30% grain, and high moisture ground-ear at 30 to 35% moisture.
* Record corn silage yields by field and quality by storage area, take samples for forage analysis
* Take Soil Samples for fertility analysis
* Take Fall Weed Survey following harvest.

* Monitor for crop condition and growth stage, white mold, soybean aphids, natural enemies, foliar diseases, sudden death syndrome (Fusarium solani f. sp. glyines), brown stem rot (Phialophora gregata f.sp. sojae), soybean rust
* Harvest when soybeans reach safe storage moisture level of approximately 13%. Review combine settings and speeds to minimize seed damage

* Continue barn area sanitation to minimize house fly and stable fly populations in and around barns
* Monitor young stock for cattle lice and mange mites
* Check condition of pastures and animals on pastures
* Evaluate need for face fly, horn fly, and stable fly control for animals on pasture. Adjust paddock rotation as needed.

* Provide annual maintenance to manure, fertilizer, and pesticide application equipment
* Prepare combines for corn, soybeans
* Sharpen chopper knives. Check shear clearances, protective shields
* Note any repairs to harvesting equipment as they are cleaned and lubricated.

Contact Information

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Julie Dennis: IPM Area Educator, Livestock and Field Crops, Western NY
Phone/Fax: (315) 252-5440

Keith Waldron: NYS Livestock and Field Crops IPM Coordinator
Phone: (315) 787 - 2432
Fax: (315) 787-2360

Ken Wise: Eastern NYS IPM Area Educator: Field Crops and Livestock
Phone: (518) 434-1690
Fax: (518) 426-3316