Crop & Pest Report

Accessibility


| Share

Scout for Soybean Aphids (06/25/20)

The first observation of soybean aphids in research plots near Harwood were found this week at very low densities and <1% of the plant infested.

The first observation of soybean aphids in research plots near Harwood were found this week at very low densities and <1% of the plant infested.

Now is the time to start scouting fields for soybean aphids in the V3 to V4 crop stage. This small aphid is yellowish-green, about 1/16 inch long, and pear-shaped with two black cornicles. They are commonly found feeding on the underside of the leaf and in the top ‘tender’ leaves of vegetative soybeans. Aphids suck fluid from plants. When infestations are large, infested leaves are wilted, yellowed or curled. All aphids excrete honeydew, a sweet substance that accumulates on surfaces of lower leaves and promotes the growth of black sooty mold.

Here’s a reminder of the correct Economic Threshold for soybean aphids:  R1 (beginning of flowering) to R5 (beginning seed) = average of 250 aphids per plant and when populations are actively increasing in 80% of field.

 

ent.2 

Janet J. Knodel

Extension Entomologist

This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

USDA logo

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.