Lawn Insect Control: Identifying & Managing Common Grass Pests

Insect damage can mimic disease, drought, or nutrient issues. Accurate identification is the first step toward targeted, effective control.

Major Lawn Pests and How to Detect Them

Caterpillars (Armyworms, Cutworms, Sod Webworms)

Perform a drench test: mix 4 tablespoons dish soap in 2 gallons water, pour over 1 square yard. Count caterpillars surfacing in 10 minutes. Treat if more than 15 per square yard using Bacillus thuringiensis (Bt) or spinosad.

White Grubs

Cut a 1-square-foot flap of sod and inspect the root zone. More than 6 grubs per square foot warrants treatment. Choose the least toxic effective product and follow timing instructions precisely.

Chinch Bugs

Look for expanding yellow patches 2–3 feet wide, especially in drought-stressed areas. Reduce thatch and water consistently to discourage them. If chemical control is needed, use trichlorfon, bifenthrin, or carbaryl as a last resort — these harm beneficial insects.

Preventive Lawn Care

A dense, healthy lawn naturally resists pests. Water deeply but infrequently; overseed thin areas spring and fall; use regionally adapted grass; fertilize appropriately; aerate annually; mow high with sharp blades.