People walking through a field infested with cereal leaf beetle larvae may emerge with black stained pants legs because this black coating easily rubs off the larvae. Damage Cereal leaf beetle larvae feed on the leaves. When feeding is severe, the entire leaf becomes brown and ragged. Cereal leaf beetle larvae are especially damaging when they feed on the flag leaf and when large numbers of larvae are found before head emergence. Scouting and Insecticide Recommendations Begin checking for cereal leaf beetle adults, eggs, and larvae in early March in the vicinity of Talladega County, AL, mid-March in the Tennessee Valley region, and late March or early April in northern Georgia.
Check fields weekly for about a month.
Check the middle of the field as well as the edges. One way to check fields is to walk back and forth in the field in a zigzag pattern. Look for feeding damage, adult beetles, eggs, and larvae. Stop in five to ten areas in each field, and count eggs and larvae on the top two leaves of five stems. If cereal leaf beetle larvae have begun to hatch and there is more than one cereal leaf beetle egg or larva per two stems, treat with one of the suggested insecticides.