Brown patches in a healthy lawn can be caused by various factors, including drought, dog urine, fungal diseases, pests, or excessive fertilizer. However, many homeowners often blame grubs. To determine if grubs are the culprit, it’s essential to test your lawn.

How to Test for Grubs

Grubs are the early life forms of beetles, such as European chafers, and Asiatic, Japanese, and Oriental beetles. They live close to the surface under lawns and other plants, feeding on roots and disconnecting them from the plants’ top growth. To confirm their presence, dig up a 3- to 4-inch-deep, 12-inch-square section of symptomatic lawn that partially overlaps the border of healthy grass.

If grubs are present, the whitish, brown-headed, half-inch to 1-inch-long beetle larvae will be visible either on the underlying soil or on the underside of the sod-like square you removed. They’re generally curled into the shape of the letter C. Fewer than 10 grubs per square foot of soil is normal and does not indicate an infestation.

Treatment Options

If you find 10 or more grubs per square foot, treatment is necessary. Heavily infested lawn sections will easily roll up like a carpet when you attempt to remove them, their roots severed by the feeding insects. Treatment should be applied in late summer when grubs are most vulnerable.

Milky spore powder is a natural product that targets Japanese beetle grubs. However, it’s not always easy to discern between species. Beneficial nematodes are microscopic, non-segmented worms that attack soil-dwelling insects, including all types of grubs. They’re a more universal approach with higher success rates.

Original reporting: Texarkana Gazette — read the source article.