‘Economic Threshold’ which, by its very nature, must be determined based on current crop value and treatment cost, as well as how many worms are your field. Fortunately, you have access to a quick, easy to use ‘Corn Earworm Calculator’ on the web that will provide instant thresholds. Hit this address http://www.ipm.vt.edu/cew/ and enter 1) the insect sampling method you are using (e.g., sweep net or beat cloth), 2) the estimated control cost (insecticide + application cost), 3) the bushel value, and 4) the row spacing of the soybean (e.g., 7-inch, 14-inch, 36-inch). After selecting your options, hit the ‘Update’ button and the calculator will instantly display the number of worms needed to meet the threshold, based on your exact situation. REMEMBER, a lot of money can be saved every year if you check fields and abide by these ‘research generated’ thresholds.
“For more information on this or other topics related to soybean production, contact your state extension specialist or your local extension educator/agent.”
The following is the link to the soybean extension specialists: state extension soybean specialist
