How To Kill Armyworms In The Lawn And Garden
This Army Could Destroy Your Lawn...

The army I'm referring to is Armyworms...and they do invade like an army. During an invasion they can strip a large tree of most or all it's leaves in just a few days or less. Where I'm at in mid-Georgia, these invaders usually show up sometime in August or September, earlier the further north you go.

Armyworms, also known as "tent caterpillars," got their name because they travel in small armies, eating everything in their path. They are a common pest of lawn grasses, especially on Bermudagrass, and will also eat any type of broadleaf tree except for maples. They also like fruit trees, berry plants, and many types of garden plants, such as beets and beans.

Identifying Armyworms

Young armyworms are one-quarter to three-quarters of an inch long. At maturity they one and a half inches long. They are dark, with several light stripes down the length of the body. The head or "face" has an inverted Y on it. The adult moths are tan or brown in color, less than an inch long, with a white spot in the middle of each forewing. The egg-laying females prefer to attach masses of eggs on tree leaves.

First signs of an Armyworm infestation

The first sign of an armyworm infestation might be several birds clustered together on the lawn feeding from the ground. Although birds like to eat the worms, there's no way they can eat them all!

Damage  Armyworms Do

Armyworms can eat 60% or more of the foliage off of a tree and strip small plants clean of leaves, seriously interrupting a plants natural growth cycle. 

In lawns their damage usually becomes apparent starting close to the edges. The first sign of trouble is small patches of brown grass with the edges of the blades chewed. Some blades may be completely eaten. These spots will rapidly grow bigger. Because armyworms feed at night, there's often no obvious explanation for the damage. As the numbers of armyworms grow, entire lawns and fields can be eaten to the ground.

How To Control Armyworms

Armyworms are surface feeders and are easily controlled by insecticides when identified early enough.

Lawn & Landscape Plants and Trees. If you see 4 to 5 small armyworms per square foot in a lawn, it's time to take steps to control them. Chemical products such as Cyonara Insecticide, which contains Lamda-Cyhalothrin, are very effective in quickly controlling armyworms, killing them on contact. Products containing Bacillus thuringiensis, such as Dipel, are effective on small worms less than one -half inch in length.

Vegetable and Fruit Plants - When it comes to using treatments to kill armywoms on plants that will end up on the kitchen or dining room table, I always recommend using a product containing Bacillus thuringiensis, such as Dipel. It often comes in a shaker can for easy application to garden plants. Dust the leaves of trees and plants with it and the caterpillars will immediately stop eating and die.

Note: Before using a chemical always follow instructions found on product label.