Billbugs are unusual pests in Iowa, and they may be difficult to see during scouting because they fall to the ground and become covered with soil particles. Billbugs in Iowa are nearly always associated with yellow nutsedge populations. Wet field roads on May 15 made access even by a 4-wheel drive vehicle difficult, but James Russman of the Farm Service Coop in Council Bluffs said that the field had been clean tilled, but yellow nutsedge is common in the area. The most severe damage is to beans in the VC stage with less damage to V1 soybeans. Although some insecticide treatments have been applied, research shows that there is almost never any economic benefit gained from rescue treatments because the soybean plants regrow readily.
Treatment is an option only when growing points are lost, which requires huge beetle populations.
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