How to Identify and Diagnose Lawn Problems

Something looking not quite right on your lawn, but you're not sure what it is?

ļ»æWelcome To The Lawn: How to Identify and Control Lawn Pests

There are many types of pests and diseases that can destroy your best lawn. We are here to tell you how to identify them, and most importantly, how to control them.

Here are some common lawn and turfgrass pests and how to identify them:


Grubs come out of winter hibernation and start to eat your lawn's roots. By late spring, grubs enter the pupa stage to transform into beetles. The adult beetles surface in summer to feed on your garden and lay eggs in your lawn. The eggs hatch into new grubs that will begin to feed on your lawn's roots.

There are few ways to detect grubs. First, look for signs such as skunks, raccoons, and birds digging up your yard to feast on mature grubs. Next, as grubs consume the grass roots, dead patches emerge, peeling away like loose carpet. Finally, even before these patches appear, you might sense a spongy feeling when walking on your lawn, similar to freshly laid sod, signaling potential grub damage to the roots.

The key to successful grub control is to apply treatment at the appropriate time based on the product label directions. Preventative grub control products like ScottsĀ® GrubExĀ®ā‚ Season Long Grub Killer should be applied in spring through early summer before or just as the grubs hatch. Always follow label directions when applying any control product.

Lawn Moths and Sod Webworms

Sod webworms are the larvae of lawn moths. They live in the root level of your lawn and munch up the grass leaves. At the root level, you'll see small white tubes made of silky web. These pests can cause major lawn damage if their populations are high in a yard. When the weather turns hot, patches of your grass may start to turn brown. If you see little moths flying above your grass at dusk, and the brown patches start to get larger, you could have sod webworms. Look for saucer-sized brown patches where your lawn is driest. The centers of the patches may have been eaten away and replaced by weeds.

Early treatment is key. At the first sign of webworm damage, treat your lawn with OrthoĀ® BugClearā„¢ Insect Killer for Lawns & Landscapes Concentrate. It can be used in a tank sprayer or applied using an OrthoĀ® Dial N' Spray Hose End Sprayer with your garden hose. It will start killing webworms, as well as other listed insects, within minutes. OrthoĀ® BugClearā„¢ Insect Killer for Lawns & Landscapes is also available in other easy to use forms like hose-end sprayers and granules so you can choose the option that best fits your needs.

Routine maintenance is also a must. Feeding your lawn with a product like ScottsĀ® Turf BuilderĀ® Lawn Food provides the nutrients your grass needs to grow strong and protect itself from insect damage. Your lawn will begin to wilt when water is needed. As much as possible, take advantage of nature's sprinkler and rely on the rain to water your lawn. If using sprinklers, water lawns deeply and infrequently (1" of water per week is all that your lawn needs).

Mole Crickets

Mole crickets, like moles, have enlarged forelegs adapted for digging. Found throughout most of the United States, they cause the most damage to lawns in the southeast. Mole crickets can create several tunnels along the soil surface and deep underground. They feed on other insects and grass roots. On warm nights, some mole crickets can feed on plant stems and leaves at ground surface level. You may see small mounds of dirt scattered on the soil surface. Your lawn also may feel spongy when you walk on it due to the detachment of turf from the soil. Grass will eventually turn brown and die in areas where mole crickets have tunneled.

Mole crickets can be difficult to control because they stay in burrows deep below the soil surface during the day and only emerge at night. Treatments are most effective when they are applied in early summer or at the first sign of lawn damage. Mole crickets are most vulnerable when they are young (nymph stage). During this stage, they are smaller and closer to the soil surface.

To kill mole crickets in the lawn, make sure the soil is moist before application, this will encourage the mole crickets to come to the surface, then apply OrthoĀ® BugClearā„¢ Lawn Insect Killer1 or OrthoĀ® Home DefenseĀ® Insect Killer for Lawn & Landscape, following the label directions.

If you are looking to feed your lawn and control insects at the same time, reach for ScottsĀ® Turf BuilderĀ® SummerGuardĀ® Lawn Food with Insect Control. This product builds strong and deep roots, creating drought tolerant grass that stays strong and lush, even in the harshest, driest conditions. It also includes an insecticide to control listed lawn pests.

While bugs may hide in the grass and below the surface, lawn diseases are easy to identify by the damage they do to your lawn. Checking your soilā€™s condition and paying attention to weather changes also helps when diagnosing lawn problems. The best defense against any type of lawn disease is to grow strong, healthy grass. ScottsĀ® Turf BuilderĀ® Healthy Plus Lawn Food is a 2-in-1 fungicide and lawn fertilizer that prevents and controls 27 listed diseases. Here are some of those diseases, along with how to identify them:

Brown Patch

Grasses typically affected: tall fescue, perennial ryegrass, bentgrasses, Kentucky bluegrass, St. Augustinegrass

Brown patch most commonly affects lawns during hot, humid summer weather. It usually shows up as large, roughly circular, somewhat irregular patches that appear to be either dry or dead. The outside of the patch may sometimes appear to be darker than the inside. If the disease has been active for a long time, the inside of the patch may recover, leaving a ring of dead or thin grass around it. With St. Augustinegrass, a brown patch can look like a brownish interior patch with a yellow outer ring.

Red Thread

Grasses typically affected: bermudagrass, bluegrasses, fescues, bentgrasses, perennial ryegrass

Red thread thrives in cool, humid conditions like those common in the Pacific Northwest, and shows up most frequently in lawns grown in nutrient-poor soils. Youā€™ll know you have it if you see thin, red hairs or strands extending from the grass blades. Red thread can survive for years if left untreated.

Rust Diseases

Grasses typically affected: zoysia, perennial ryegrass, Kentucky bluegrass

Rust diseases appear as irregular light-green or yellow patches on the lawn, but if you look closely, youā€™ll see orange-yellow rust spores on the individual grass blades. Youā€™re most likely to see this disease in the late summer and early fall, especially in shady areas with poor ventilation. Sometimes rust will appear in the spring if the lawn has not been fertilized properly, so be sure to feed your lawn throughout the year to help prevent it.

Snow Mold

Grasses typically affected: ryegrasses, creeping bentgrass

There are two types of snow mold: pink snow mold and gray snow mold. While snow mold generally grows under snow cover, pink snow mold can also grow during cool, wet weather when thereā€™s no snow on the grass. It appears as grayish-white or whitish-pink patches of crusty, matted grass, and is most noticeable in early spring when the snow begins to disappear. Learn more about snow mold right here.

snow mold

Summer Patch

Grasses typically affected: Kentucky bluegrass, fescues, annual bluegrass, bentgrass

Summer patch usually appears between June and September, during periods of high humidity when daytime temperatures are over 85 degrees. It will show up in the form of irregular brown patches, rings, and crescent shapes. While the disease may still be present during cooler weather, the symptoms won't be as apparent.

If you identify one of these diseases on your lawn, donā€™t panic. Simply apply ScottsĀ® Turf BuilderĀ® Healthy Plus Lawn Food to prevent disease before it appears and/or to control disease at the first sign. This 2-in-1 lawn fungicide and fertilizer not only prevents disease, but also feeds your grass. With our knowledge and product offerings, we can help you identify lawn diseases and pests as well as provide the best method to treat the most common lawn problems.

summer patch disease