A green soybean field against a blue sky

(Photo: Joseph L. Murphy/Iowa Soybean Association)

Efforts to control soybean gall midge

March 5, 2021 | Drew Clemmensen

Soybean gall midge first appeared in Iowa’s western counties in 2018. Since then, the 2-to 3-millimeter-long fly and its destructive larvae — which feed on soybean plant tissue creating galls, tissue swelling or growth — has expanded its known presence to 32 Iowa counties stretching east from the state’s western border. The Iowa Soybean Association is researching how to control soybean gall midge and studied the performance of two products in a 2020 trial. Drew Clemmensen, ISA field services program manager, says studies will continue.

“Two products we tried in 2020, Fortenza by Syngenta, a seed treatment product and the second — Thimet by AMVAC — a granular product that goes infurrow only available in smart boxes,” Clemmensen says.

Reviewing the data, Clemmensen also outlines some of the information gained from a Dordt University-owned plot using Thimet, showing the product holding slightly less than a four-bushel yield advantage against the untreated control.

“That was planted in a small plot with a 12-row planter, they actually had three treatments in this: untreated, counter-product and the Thimet as well on corn soybean rotation,” says Clemmensen.

ISA will continue to work alongside Iowa State University researchers to continue efforts to control the pest. He encouraged producers to reach out with any ideas or thoughts related to soybean gall midge detection and management.

Watch the video examining the 2020 trial in full detail below.