State warns of new batch
of army worms hitting hay, corn

State Agriculture Commissioner Darrel J. Aubertine has alerted crop growers that a second generation of armyworms has been reported in western and northern New York. This pest quickly devastated fields of hay and corn earlier this growing season.

Farmers should be scouting fields for the presence of this second generation. The caterpillars are very small at this time — about ¼ inch long. This small size makes this an optimal time to implement control measures.

Caterpillars of the armyworm are most readily found in early morning as these are night feeders. During past infestations the second generation did not cause a lot of damage — but the high levels seen in western New York this June and the drought make damage levels unpredictable.

The true armyworm (Mythimna unipuncta) that has been seen in especially heavy levels in western New York is an excellent flier in its adult moth stage. This pest is not seen annually in New York since it does not overwinter in the state’s cold climate. Occasional infestations occur when the adult moth stage flies up in the spring from southern states such as North Carolina.

The New York State Integrated Pest Management (IPM) program, Cornell Cooperative Extension Educators and crop consultants continue to monitor and report on this crop according to Keith Waldron, New York State IPM Livestock & Field Crops IPM Coordinator. Weekly field crops reports are available at: (

This insect is called armyworm because in its caterpillar stage it often will move in a mass, marching in lines from one destroyed field to their next feeding ground. They have been found in New York in small grains, corn, mixed stands of alfalfa, turf grass, grass and hay fields, but have been known to also infest various vegetables, fruits, legumes, and weeds, including beans, cabbage, cucumbers, lettuce, onions and peas.

Control measures must be applied with added care to avoid crop damage due to current drought conditions. Only pesticides that are labeled for use on armyworm and the specific crop being treated can be used.

For specific information on how to detect and control this pest contact your local Cornell Cooperative Extension agent (