Insects on Bermudagrass

Bermudagrass (Cynodon spp.) is a warm season type of turf used for residential lawns, athletic fields and golf courses in the South where winters are warm and rainfall is moderate to high. In frost-free climates, it remains green year-round with smooth, pointed leaves that spread by stolons and rhizomes. Bermudagrass is subject to a number of lawn pests that can cause damage to the appearance and health of the lawn.

Armyworms

Armyworms are generally tan or brown and can grow up to 1-1/2 inches long. They feed at night, devouring grass plants and leaving spotty dead spots that spread from area to area. Bacillus thuringiensis, a bacteria that infects and kills the young larva, is a good biological control for armyworms. Carbaryl pesticide helps more serious infestations.

Cutworms

Cutworms are the larval stage of several different types of moths. They are so named because of their feeding habit of chewing grass plants as if they were cut, destroying more of the plant than they actually eat. Cutworms vary in color from brown or tan to pink or grayish. Many are smooth and stout-bodied. Carbaryl or permethrin insecticides will help to control infestations.

White Grubs

White grubs found in bermudagrass are the larval stage of a variety of insects such as Japanese beetles, May beetles, June beetles and chafer beetles. The larva chew the roots of bermudagrass plants, causing patches of browned, dead foliage that can spread over wide areas of the lawn. Treatment for some species of white grub include the use of milky spore, a biological control that is safe for the environment, according to Texas A&M University turf specialist Richard L. Duble.

Sod Webworms

Sod webworms are the larval stage of a buff-colored moth. The worms are about one inch in length with light or dark spots along the body. The worms emerge at night to chew on grass plants at the thatch line. Their feeding causes small, dead patches and thinning in the bermudagrass in mid-summer. Bacillus thuringiensis helps to control infestation. Beneficial nematodes, such as the Steinernema variety, are effective in controlling older larva, according to Ohio State University writer David J. Shetlar.

Bermudagrass Mite

The bermudagrass mite is a tiny, yellowish-white, worm-shaped insect that causes yellowing and curling of bermudagrass leaves. A serious infestation can cause lawns to lose vigor, thin and die. Reducing the use of fertilizer and close-mowing help to control small areas of infestation, but serious problems require the use of bifenthrin or lambda-cyhalothrin pesticide.

References

• Texas A&M University; Bermudagrass; Richard L. Duble
• Ohio State University; Sod Webworms; David J. Shetlar
• University of Florida; Bermudagrass Mite; E. A. Buss
• University of Maine; Armyworms; James F. Dill & Clay A. Kirby