Fix Lawn Spots - Problem: Grubs

By the DIY experts of The Family Handyman Magazine

An ounce of prevention
Inspect your turf periodically by pulling on patches that look unhealthy,
or have a professional inspect your lawn if you suspect a problem.

Photo 1: Check for grubs
Pierce lawn with a shovel in a U-shape.
Peel back the lawn (as though rolling up a rug)
 and count the white grubs in a 1-sq.-ft. area.

Photo 2: Treatment
Treat your lawn with an insecticide if the count is six to 10 grubs in a square foot.
Follow the manufacturer's directions carefully. Or consult with a yard service.

Moles love grubs
A grub problem is often indicated by increased mole, bird and raccoon activity. They dig up and feed on grubs at night.This may sound good, but moles kill your grass along with the grubs.(Photo by fotosearch.)

Symptoms: Grub-chewed turf has patchy areas that wilt and die. You can easily pull up the affected turf if you tug on it. Another indicator of grubs may be increased raccoon, bird or mole activity. They like to dig up and eat the grubs at night. While this may sound good, the moles will kill the grass as they forage for grubs.

Cause: Lawn grubs are the larval stage of moths and beetles. The grubs eat the roots of grass, setting them up for death by dehydration.

Remedy: Be vigilant. Are beetles swarming around your porch light? In the next month, keep an eye out for patches of grass that wilt or are blue-green on hot days. They may be larvae infested. Turn over some turf (Photo 1). If you count six to 10 grubs (white wormlike larvae with black heads) under a 1-ft.-square area of sod, consider using a grub insecticide (available at home centers and nurseries). Or talk to a professional (search “Grass Service” online) about treating your yard. They will be familiar with the grub problems in your region and the most suitable treatment methods.

If you spot the grubs but your count is lower than six per square foot, baby your lawn to strengthen its natural defenses. Mow on higher blade settings and water thoroughly but infrequently to encourage the grass to grow new, deep roots. Do not cut off more than one-third of the grass height at each mowing, to avoid stressing the plant.

CAUTION!

Call your local utility provider or 811 to mark your underground utility lines before you dig.