Couplet 26

10/22/2010 3:14:20 AM

Jagged cutting damage, removing part or entire leaf, but leaving midrib intact.
Mowing type damage to vegetation; larva present with inverted "Y" shape on head.

Insect may be:


Photo by: Natalie Hummel and Johnny Saichuk

adult moths are about 1 inch long with gray-brown sculptured front wings and whitish hind wings. Females lay egg masses on leaves of rice and other grasses in and around rice fields. The larvae emerge begin feeding on rice plants. They vary from light green to brown to black, with distinctive white stripes along the body. Larvae feed for two to three weeks, developing through four instars. Mature larvae pupate in soil or decomposing plant material. Moths emerge in one to two weeks, mate and disperse widely.


  • Fall armyworm is an occasional pest on rice.
  • Fall armyworm larvae feed on the leaves of young rice plants, destroying large amounts of tissue.
  • Seedlings can be pruned to the ground, resulting in severe stand loss.
  • Fall armyworms infest field borders, levees and high areas of fields where larvae can escape drowning.

What you should look for:

  • After germination of seedlings, scout fields weekly for larvae on plants.
  • Mature larvae are about 1 inch long and have a distinctive inverted “Y” on the head.

How you can manage the fall armyworm:

  • Sample plants every 10 feet along a line across the field, and repeat this process in a second and third area of the field.
  • Treat when there is an average of one armyworm per two plants.
  • Reduce larval infestations by effective management of nearby grasses.
  • Flood infested fields for a few hours to kill fall armyworm larvae.



For more information, please see the Rice section of the Insect Pest Management Guide on the LSU AgCenter's Management Guides webpage.

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