How to identify a Fall Army worm

Fall Army worm eggs are normally

  • whitish/cream in color when fresh,
  • but turn dark when they are about to hatch.
  • They are also normally covered in fine hairs.

In addition, they can be found in clusters of 150-200 on both sides of the leaves.

 

Fall Army worm caterpillars (larvae) normally have:-

  • an inverted Y pattern on the head
  • 4 black dots forming a square on the eight segment towards the tail.

The fall army worm caterpillars normally range in colour from green to brown and grey to black. They like hiding in the funnels during the day to prevent being seen.

Image: Syngenta seed care

Newly hatched caterpillars are normally black in color, and move in a mass away from the other eggs towards the maize funnel.

They normally hide inside the maize whorl during the day and mainly come out during sunset and early in the morning. This is mainly to feed and cause crop damage.

If you detect tiny holes, large ragged holes and orange sawdust-like material on leaves, be sure that you have Fall Army worm infestation in your crop.

Fall Army worms are cannibalistic and tend to fed on younger caterpillars.

Fall Army worm moths

The moths can fly long distances in a single night, mate and lay eggs. A female moth can lay up to 1500eggs in her lifetime.

 

Image: Bugguide

Difference between a fall army worm and African  army worm

African army worms may seem similar to fall army worms, but have some distinctions. The fall army worm normally creates small holes in the stem of maize crops which is contrary to African army worms.

For African army worms, they normally hatch somewhere outside the farm and then steadily eat their way through everything in their path as a group. However, for the fall army worm moth it lays its eggs on the host plant.  The larvae fall army worm does not eat everything, but as it grows moves up the maize plant causing more damage.  The fall army worm also makes a lot of yellowish debris and whitish powder on the leaves and funnel where they are.