The rapid gains in soil insecticide use are attributed to the growth of continuous corn acres, control breaks in corn rootworm single-trait hybrids and increasing challenges from secondary insect pests, according to AmVac Chemical Corp.
Fifteen years ago a little-known version of the western corn rootworm, called the soybean variant, showed up in Jim Brown’s corn crop with a big appetite.
"It was pretty devastating to yields that first year because I had no idea it was there," Brown recalls.
Unlike typical rootworms that lay their eggs in corn, the soybean variant flies into soybean fields to lay its eggs. This practice allows the larvae to hatch the following spring in a field likely planted to corn. That means a standard corn-soybean rotation is unable to keep the pest in-check, which was the case for Brown. He turned to granular soil insecticides for help and has used them ever since to stop rootworms in their tracks.
This spring, Brown can expect a lot of company from like-minded farmers, based on current soil insecticide sales projections. Treated acres are projected to top 15 million acres acres, a 40-plus percent increase over 2012, according to Joe Short, Midwest marketing manager for AmVac Chemical Corp.
The sudden surge in soil insecticide use the past couple of years has reversed what had been a trend toward reduced use; applications dropped to an all-time low in 2006.
Short attributes farmers’ rapid re-adoption of soil insecticide use to the growth of continuous corn acres, control breaks in corn rootworm single-trait hybrids, and increasing challenges from secondary insect pests.
Why Corn Acres Continue to Grow
Courtesy of AmVac Chemical Corp.
"Growers want to reduce risk and increase yields," he says.
The challenge for corn growers is to balance productivity and profitability with technology and environmental stewardship, says Ron Hammond, Ohio State University Extension entomologist. He cautions farmers about using soil insecticides in fields planted to transgenic corn hybrids.