fall armyworm late instar MER copy.jpg

Fall armyworm moth


  • Adult: Gray and brown moth with triangular white spots on each forewing and a wingspan of 1½".
  • Larvae: Smooth-skinned caterpillar, ranging in color from light tan or green to black with three light yellow stripes down the back. Distinguishing feature is a white inverted "Y" marking on the front of its brown head. Grows to about 1½".
  • Eggs: Dome-shaped with a flattened surface and a rounded point at the tip. Female covers the egg mass with a layer of gray scales, giving the mass a moldy appearance. 

Timing of damage: All growing season

Type of damage: Leaf and pod feeding; sometimes fall armyworms will cut the stems of seedlings.

Scouting: Examine whole plants in rows, use a sweep net or shake the plants onto a drop cloth. 

Economic threshold: Eight caterpillars per row-foot, or if the number of cut seedlings is putting the field below the recommended stand density.

Similar Pests

Ask an Agronomist

The material and content contained in the Greenbook label database is for general use information only. Agworld and Greenbook do not provide any guarantee or assurance that the information obtained through this service is accurate, current or correct, and are therefore not liable for any loss resulting, directly or indirectly, from reliance upon this service. This label database does not replace the official manufacture issued label. Users of this database must read and follow the actual product label affixed to the container before use of the product.