Fall Armyworm

Found year round in subtropical areas such as southern Texas and Florida. They gradually migrate north with warm eather and can often reach all the way up to Canada by fall.

Adults are mottled dark brown-gray moths with lighter markings on the bottom set of wings. Newly hatched larvae are white with dark heads. Mature larva are greenish-brown with white subdorsal lines and brownish black stripes above spiracles, and pale stripes with reddish brown mottling below. Mature larva are about 2 inches long and have a prominent inverted "Y" on front of its head. Both moth are larva are active at night. Adults lay masses of 50-100 eggs that hatch about 3 days later. Larvae eat tender plant parts for 12 days, then move to pupate in the soil for 12 days. The moths emerge and mate on the second night and lay eggs on the third night. Very fast life cycle meaning the pests will spread very rapidly through your garden.

These pests munch on corn, grasses, cabbage, cotton, tobacco, peanuts, etc. Symptoms vary with plants. On corn they chew leaves and bore into ears and stalks. On other plants, they mostly damage the leaves and stems.

The best control is a soil dwelling nematode called Steinernema riobravis which parasitizes and feeds on the pupa stage in subtropic areas. An almost microscopic wasp, cotesia marginiventris, attacks small larvae. A tachinid fly parasitizes the larger larvae. both wasp and fly are found throughout the southeast. Other controls include fast maturing corn that will mature before the annual fall invasion which starts around July 4 in the south and early August in Pennsylvania areas. Grow corn varieties with extra tight husks. Bt is not effective.

Very very naughty pest. Will wipe out a corn field within a couple months if preventive measures are not taken. Other crops don't suffer as much as corn, but there could be some damage.

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