Insect Appearance: The armyworm caterpillars are light tan to dark brown with yellow, orange, or dark brown stripes down the lengths of their backs. They are 3/4 inch to 2 inches long. Adult moths are tan or mottled gray with a wingspan of about 1 inch. They fly only at night or on overcast days. In daylight, they hide in the soil around grass roots.

Life Cycle: Moths appear in late spring to early summer and lay hundreds of eggs at a time on the grass. Larvae hatch from eggs within 10 days and begin feeding. You may see the larvae hanging from threads on the grass. In the south, there maybe as many as six generations a year.

Damage Threshold: More than five larvae per square yard indicates infestation.

Symptoms: A Small and distinct circular pattern becomes yellowish or brown when billbugs are feeding on the lawn. Since the larvae feed on roots, grass plants within the dead areas easily lift out of the soil. a white sawdust-like debris can be found on the ground around the affected plants.

Insect Appearance: Billbug larvae-which do most of the damage-are white, legless grubs about 3/8 inch to 1/2 inch long. Brownish-gray adults have long snouts used for burrowing and chewing off plants.

Life Cycle: Overwintering adults emerge in mid-spring, when they often can be found crawling on sidewalks and driveways. soon after emerging, they lay eggs on the stems of grass plants. Grubs generally emerge in May or June and then tunnel into the stems, from where they eventually will migrate into the root zone.

Damage Threshold: More than one grub per square foot of lawn.

Insect Appearance: Adult chinch bugs are small, from 1/16 to 1/4 inch long, depending on the species. Most are black with white wings, each of which has a distinctive triangular black mark. Young chinch bugs are smaller wingless versions of their parents, but are red with a white back stripe.

Life Cycle: Adult chinch bugs over winter in both the North and South and emerge as early as March, from the rest of the growing season, they feed by sucking the juice from grass blades, injecting a poison that causes blades to turn brown and die. They are especially active during hot, dry weather.

Damage Threshold: To find chinch bugs, push a bottomless 2 pound coffee can into the affected lawn area, about 2 inches deep. Fill it with warm water. Any chinch bug present should float to the surface. If more than 20 chinch bugs appear, controlled is warranted.

Symptoms: As with armyworms, cutworms leave small, 1-to-2 inch wide patches of brown grass in newly seeded and established lawns; the plans are eaten off at soil level.

Insect Appearance: The larvae of cutworms are plump, smooth, and almost always curl up when disturbed. They can be various in color but are most often gray, brown, black; some are spotted or striped. They often grown to 2 inches long. The moths are dark and fly at night.

Life Cycle: Moths lay their eggs in late summer, and after hatching, cutworm larvae over winter in trash clumps of grass. Larvae resume feeding early in the spring (and only at night). they mature into moths in July or August.

Damage Threshold: Use the pyrethrum test, to determine how pervasive these insects are. If you find more than 10 larvae per square foot, it's time to act. Cutworms don't seriously damage grass unless there is a severe infestation. More damage may be done by birds scratching at the turf to feed on the larvae.

Symptoms: One-to two-inch-wide dead patches with grass blades chewed off just above the thatch line. Usually prevalent in the hottest, driest areas of the lawn. Silky, white tubes found nestled in the root area.

Insect Appearance: Sod webworm larvae are slender, grayish, black-spotted caterpillars, approximately 3/4 inch long, and sluggish in their activity. They hid during the day in shelters constructed of bits of grass and debris. The buff-colored moths, which fly in zigzag patterns over the lawn at dusk, have two snout-like projections on their heads.

Life Cycle: Over-wintering larvae emerge and begin feeding (at night or on overcast days) in spring. They mature into moths in early summer. Throughout the summer, the moths fly over the grass and drop eggs, which hatch into larvae and repeat the feeding cycle on the grass. There may be as many as three generations per season.

Damage Threshold: Fifteen or more larvae per square foot indicates treatment as necessary.

Symptoms: Irregularly shaped brown patches of turf, particularly in late spring or early fall. Dead patches of lawn roll back easily, like a section of carpet. Birds, moles raccoons, and skunks may damage a lawn looking for grubs.

Insect Appearance: White grubs have a curled C-shaped bodies from1/4 to 3/4 inches long. They are creamy white with yellow or brown heads and dark hind patterns. Adults vary in appearance because white grubs are the larvae of scarab beetles, June bugs, rose chafers, Asiatic beetles, and others.

Life Cycle: Grubs over winter and begin feeding early in spring. Adult beetles appear around late spring or early summer. A second generation emerges in late summer and feeds in autumn.

Damage Threshold: Watering is recommended after application to carry pesticides down through the grass and thatch into the soil level where most of the grubs live.

Moles damage lawns as they search for insects on which to feed.

Moles and gophers are rodents that live underground. Moles feed on earthworms, grubs, and other insects; gopher eat plant roots or entire plants. Each causes damage to the lawn by severing grass roots, raising sod, and in the case of gophers, eating sections of the lawn.

Moles are 6 to 8 inches long with gray to black velvety fur. When moles are present, you will notice raised ridges, 3 to 5 inches wide, that crisscross the lawn. These ridges sometimes turn to brown because the tunnels have destroyed the grass roots.

Gophers are brown, with small eyes and ears and conspicuous pouches on either sides of their mouths. Gophers create crescent-shaped mounds of soil on the lawn on the lawn, On close probing, you will find a hole underneath each mound. Gophers usually are found in the western United States.

Trapping or baiting is the best way to eliminate gophers from your yard. Moles are harder to control with traps or poisons because of the fragile, temporary nature of their tunnels. The best way to help rid you lawn of moles is to eliminate their favorite food - grubs.