Army worm are the caterpillars of the army worm moth.

The moth lays eggs that hatch and go through multiple stages before they turn into a pupa and become moths.

When the eggs first hatch the worms are green and only 2-3mm long.

The adult worms are 3-4 cm long and cause significant pasture damage.

If your farm should be growing and it isn’t that is a real sign of army worm.

Pasture may look dry and scraggly even if irrigation is up to date. This is because the worms feed on the tips and outer edges of the leaves.

You will see complete dead areas of grass when they are causing maximum damage.

They tend to only eat at night and spend the daytime either at the plant base or curled up on the ground.

Look in the sward on the ground. This pasture looks fine.

But open it up and you’ll find them.

You need to check multiple paddocks in multiple locations if it is present in the area. You need to do this daily.

Often you’ll pick them up early while doing a pasture walk as they accumulate on the plate meter.