Dr. Heather Darby, UVM Extension
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Armyworm damage has been reported in Maine. Please don’t panic, but do go out and scout your corn and grass fields for armyworms. When full grown, the caterpillars can be almost 1.5 inches long. The caterpillars are usually greenish or brownish, but can be almost black. The sides and back of the caterpillar have light colored stripes running along the body. The caterpillars normally feed at night and much damage can occur before they mature. The preferred foods are grasses including corn, grains, and timothy. They will feed on other plants if grasses are unavailable. Feeding will start on the lower leaves and move upwards. A large population can strip an entire field in just a few days. When the field is eaten they “march’ to adjacent fields. Corn fields that are minimum or no-tilled into grass sod or fields infested with grass weeds are most susceptible. For more information on scouting and control options please contact Dr. Heather Darby at the University of Vermont Extension at (802) 524-6501.