Agronomic Crop Insect Scouting

David Owens, Extension Entomologist; owensd@udel.edu

Early Season Moth Activity

Trap Location True Armyworm per night Black Cutworm per night
Willards, MD 0.4 1
Salisbury, MD 0 5.3
Laurel, DE 0 6.3
Seaford, DE 2.4 7.7
Bridgeville, DE 0.1 3.0
Harrington, DE 0.4 5.6
Smyrna, DE 1.5 5.9
Kenton, DE 2.1 2.1
Pearson’s Corner, DE 0.4 0.9
Sudlersville, MD 0.1 0.7

Small Grains
Aphid pressure has been declining due to presence of entomopathogenic fungus. Cereal leaf beetle larvae are active. Continue scouting for grass sawfly and true armyworm, especially in barley that has already received a head fungicide application. We are starting to fall into the pre harvest interval concerns. All pyrethroids but Mustang Maxx have a 30 day PHI.

Field Corn
Now that corn is up, be sure to scout fields for seedling pest damage. Soil pests should be adequately controlled by seed treatment. There is no rescue treatment for them. Affected plants will appear heavily stunted and wilt. Cutworms will leave a row of circular holes in the emerging leaves when they are small and cut plants when they get larger. Small cutworms should be controlled by seed treatment and traits. Action thresholds when plants have less than 2 leaves are 3% cut plants and 10% leaf feeding. For larger plants, thresholds are 5% cut plants.