Take Action Fast
if you see these in your lawn, you could be just a day or two away from devastation under the right unfortunate circumstances.
A large infestation of armyworms can devastate a lawn in a few days. Armyworms feed on grass blades and are the larvae of a moth and generally are a pest in the South. Armyworm moths can however, ride fronts that take them North and show up in unexpected places.
The moths can be identified as follows:
- • Adults are tan or brown moths less than an inch long, with a white spot in the middle of each forewing.
- • Egg-laying females usually prefer to attach eggs on tree leaves.
As worms, they are described as follows:
- Light green or tan in their early growth stage and dark green or brown in later stages.
- Full grown, they are 1½ to 2 inches long and almost hairless.
- •They can be identified by a series of green, yellow, or brown stripes down the length of their bodies.
Identifying the Damage and Signs
The first signs of the damage look just like heat stress to the lawn which can be deceiving. Usually, the ends of the blades are chewed, leaving brown patches. In heavy populations, these blades may be completely eaten away.
Your lawn is in the most danger during hot and dry weather and when the infestation reaches a high level!
The Good News and Treatment
Because Armyworms feed on the surface, they are relatively easy to control with insecticides. There are multiple insecticides that are effective in killing them. One common insecticide we recommend has the active ingredient "Bifenthrin". If you spray them before they cause much damage, your lawn will recover nicely. When just the edges and tips of the blade are damaged, the grass will recover by keeping it well fed and watered.