Insecticides for Turf

Finding the Bugs

• Scout the lawn for insects or telltale signs of damage. Look at both damaged and undamaged areas, since insects move on when the area they're infesting dies. Insects in dead patches are generally not the culprits. Timing is everything. Once you know which insect is pestering your lawn, find out the best time to kill that particular species with pesticides. Every insect has a vulnerable stage, usually the larval stage. This is normally the best time to apply insecticides.

Root Feeding Insects

• The larval stage of several beetles feed on turf roots. These are all called grubs, and several pesticides are available for eradication. When grubs infest the lawn and eat the roots, you can pull up the turf like a piece of carpet. Grubs hide in the turf, emerging as adult beetles. May/June beetles, Japanese beetles, scarabs, masked chafers and other beetles lay their eggs in the turf. Billbugs lay their eggs in grass sheaths, and the legless, white larvae feed on grass stems and roots. Insecticides containing halofenozid, carbaryl, chlorpyrifos, imidacloprid, isofenphos or diazinon control grubs. Pesticides containing acephate, halofenozid or imidacloprid on billbug larvae, chlorpyrifos or carbaryl kill adult billbugs, and isofenphos or diazinon eliminates both adults and larvae.

Grass Blade Defoliators

• Sod webworm larvae are about 3/4 inch long. They have black heads and feed on grass blades at night in summer. Cutworm moth larvae are large, about 1-1/2 inches long and may be black, dark gray or bronze. Cutworms roll into a ball when disturbed and hide in the soil during the day. Insecticides that kill sod webworm include products containing acephate, carbaryl, chlorpyrifos, halofenozid, isofenphos or diazinon. Insecticides containing acephate, carbaryl, chlorpyrifos, diazinon or isofenphos should work on cutworm infestations.

Grass Blade Sucking Insects

• Leafhoppers may be less than 1/4 inch long and are green or gray. They lay eggs in the leaf tissue and suck juice from the grass blades. Their young, called nymphs, also suck on grass blades. Most new lawns do not require treatment. If leafhoppers cause major damage, treat the turf with products containing acephate, carbaryl, chlorpyrifos or diazinon. Small, yellow or green flying insects called greenbugs are a member of the aphid family. Run your palm across a patch of grass. If greenbugs are present, they rise in a cloud. Greenbugs are sapsuckers and feed in shady areas of turf. They are especially fond of bluegrass. Greenbugs reproduce prolifically. As soon as you find them on the lawn, treat with pesticides containing acephate or chlorpyrifos. Chinch bugs start out red but turn dark as they mature into 1/5-inch long adults. True chinch bugs have a black triangle on their forewings' margins. False chinch bugs, which are harmless to lawns, do not have the black triangle on the wings. Use pesticides only in severe infestations. Look for a product that contains acephate, carbaryl, chlorpyrifos, isofenphos or diazinon.

Ants

• Most ants do not harm lawns. Fire ants bite humans, and the field ant, which builds large, tall nests that interfere with the lawn's growth and the lawn mower, can be a problem. Liquid or granulated permethrin or carbaryl products, granulated bifenthrin or cyfluthrin, or liquid acephate products kill ants.