Lawns: Mole Crickets

Problem
Small mounds of soil are scattered on the soil surface. The lawn feels spongy underfoot. Large areas of grass turn brown and die. To determine if the lawn is infested with mole crickets, make a solution of 1 ounce of liquid dishwashing detergent in 2 gallons of water. Drench the mixture into 4 square feet of turf. Mole crickets, greenish gray to brown insects, 1½ inches long, with short front legs and shovellike feet, will come to the surface within 3 minutes.

Analysis
(Scapteriscus and Gryllotalpa species)

Several species of mole crickets attack lawns. They prefer bahia- and bermudagrass but also feed on St. Augustine, zoysia, and centipedegrass. They damage lawns by tunneling through the top 1 to 2 inches of soil, loosening it, and uprooting plants, causing them to dry out. They also feed on grass roots, weakening the plants. They feed at night, and may tunnel as much as 10 to 20 feet a night. In the daytime, they return to their underground burrows. Adults migrate from their burrows to new areas twice a year, in the spring from March to July and again from November to December.

Solution
In June or July, after the eggs hatch and before the young nymphs cause much damage, treat the lawn with an insecticide containing chlorpyrifos or diazinon. Mow and water before applying, since mole crickets are not active in dry soil. Do not water for 36 hours after application. If damage continues, treat again in late summer to early fall. Keep the lawn watered to encourage new root growth.