Soybean Aphid 2004

Mark Carlton, southeast crops field specialist

Problem

During the summer of 2003, soybean aphids reduced soybean yields up to 15 bushels per acre across the Midwest.  In June of 2004, soybean aphid populations were reported near Burlington, Iowa.  Local soybean producers and agri-business were frantically scouting soybean fields for aphid populations and were ready to begin applying insecticides.  I received a call from an agchem dealer in Weaver, Iowa, located just south of Burlington, that local producers were finding aphids in their soybean fields and wanted information on economic thresholds for soybean aphid.

Response

I scheduled a visit to Weaver the next morning and invited the agchem dealer to have local soybean producers bring plants into the dealership for evaluation.  Bob Dodds, Lee County Extension Education Director, and I arrived at the dealership at 9:00 AM. We examined the plants and determined that the insects on the soybean plants were not soybean aphids but were soybean thrips.  We spent approximately two hours working with both the agchem personnel and 8 local producers on the identification of soybean insects.

Impact

The 8 producers who brought plants to be evaluated represented approximately 4,800 acres of soybeans.  The agchem dealer scouted an additional 5,000 acres of soybean.  Both were prepared to begin applying insecticides.  The cost of insecticide application for soybean aphid was $12.00 per acre.  A two hour field visit by Bob Dodds and I saved Lee County producers more than $100,000 in insecticide application.  In addition to the soybean thrips, we found soybean cyst nematodes on plants brought in by two producers.  We visited with the group on how to scout fields and control soybean cyst nematodes.

Sept. 15, 2004
142 - Integrated Pest Management/Integrated Crops Management

Page last updated: July 9, 2006
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