Lawn Pests

A lawn is a monoculture planting, that normally dominates our properties.  Due to its single plant nature and that it is repeated from neighbor to neighbor, it is very susceptible to disease and pests that quickly spread.

Ideally you want to minimize your lawn size to what your family needs and compliment it with a landscape of planting beds to help create a diversity of micro environments that can provide friendly habitats for our birds and bees.

The best preventive to many of the pests discussed below is a healthy lawn. Two of the most common mistakes made by lawn owners is over watering and cutting too short.  A lawn only requires 1″ of water a week (including rainfall) and is best watered infrequently but deeply – achieve your 1″ in just two waterings.  Mowings should be done at 2½ to 3½ inches.  A longer lawn keeps the weeds down, doesn’t stress your grass and helps retain moisture.

As much as properly maintaining your lawn helps prevent pests and disease, trouble can still come despite our best efforts.  In this section we discuss the more common pests our lawns encounter here in SOMA.


The white grub is the most widespread and destructive lawn pest in our region.  Grubs are the larvae of a number of beetle types including the Oriental & Japanese beetles.

They damage the grass by eating the roots closest to the surface, disconnecting the grass from its roots.  They are the most destructive in mid-summer to early fall as they move closer to the surface.  An unusually warm spring will start an earlier grub season.


Early signs of infestation include thinning, yellowing, and the appearance of scattered dead patches. The infected areas feel spongy when walked on and can be pulled up easily like a carpet. Often secondary damage can be caused by predators (skunks, raccoons, moles), that tear up the turf to feed on the grubs.

Preventive Control

Your local garden center will offer many types of grub control, often mixed in with a seasonal fertilizer.  Grub control should be put down early summer and only in the lawn areas where grubs damage has been an issue in the past.  Putting down grub preventive throughout your entire lawn can harm good underground species.

For more information on grubs please see Rutgers EDU-An Integrated Approach to Insect Management in Turfgrass: White Grubs.

Signs of Grub Damage

Hairy Chinch Bug

The hairy chinch bug is possibly the most destructive insect of turf grass in our area.  On the positive, it takes perfect conditions for them to thrive, which under normal weather conditions in New Jersey should completely avert the bug.

It is the adult chinch bug that does all the damage, sucking sap from the grass, injecting toxins into the crowns and stems of grasses, preventing the plant from absorbing water.


Similar to slugs, the grass will show patches of yellowing, browning and dead spots. However unlike slugs, the grass will still be attached to its roots and not easy to peel away.

Preventive Control

The good news is that under normal New Jersey conditions of a wet spring most of the chinch bug larvae will drown and die. Generally, low humidity at low temperatures and high humidity at high temperatures keep the chinch bug populations under control.

If you do have an outbreak due to ripe conditions (hot, dry, low water) then there are products that can be used to control the outbreak.  Please check your local garden center for products that advertise Hairy Chinch Bug control.

For more information on Hairy Chinch Bugs please see Rutgers EDU-An Integrated Approach to Insect Management in Turfgrass: Hairy Chinch Bugs.

Sod Webworms

Sod webworms are small caterpillars that live in silk-lined tunnels in the thatch and soil below turfgrass. Adult moths are small, hovering over grass at dusk.  There are many species, common species in New Jersey include the bluegrass webworm (Parapediasia teterrella) and the larger webworm (Pediasia trisecta). The webworms  damage most cool-season grasses including Kentucky bluegrass, fescues, perennial ryegrass, and bentgrass.


Damage begins as general thinning, followed by small patches of brown. Damage is most common in sunny sites during hot, dry periods.  Flocks of birds probing in the grass may indicate webworm infestation, however, the birds may also be feeding on other insects.

Preventive Control

A healthy, vigorous lawn and balanced fertility and irrigation during dry periods will enhance the lawn’s tolerance to webworm feeding. 

Wasps, flies, predatory insects (e.g. beetles and ants) and many bird species prey on webworms from larvae to adults. Natural predators often keep webworm populations at tolerable levels.

If infestation becomes serious, then there are many insecticides available at your local garden center that focus on lawn insect control.  The label should list Sod Webworms as one of the target pests.

For more information on Sod Webworms please see Rutgers EDU-An Integrated Approach to Insect Management in Turfgrass: Sod Webworms.

Sod Webworm lifecycle
Signs of Sod Webworm damage

Red Thread Disease

Red thread is caused by the fungus Laetisaria fuciformis.  It is highly contagious, and can kill your entire lawn as well as your neighbors. You can stop the spread by wiping off your mower blades, not walking through the diseased grass then onto healthy grass.

Turf that is under stress is more susceptible to red thread and may appear first in areas with nitrogen deficiencies.


The disease normally occurs during the cooler temperatures of the spring and fall.  It starts with a wet-soaked appearance. Once your lawn dries, you’ll notice red or rust-colored bunches of threads on your lawn. The water-soaked patches appear and die rapidly.

Preventive Control

Test your soil to maintain a 6.2-6.5 pH level.  If you suspect red thread apply nitrogen rich fertilizers combined with potassium, this will promote plant growth to help fight off the disease.

Proper irrigation of very few but deep waterings in the early morning hours.  Keep your mower blades sharp and avoid cutting the grass when wet.  Grass should be kept long, 2.5-3.5 inches.  Don’t cut it below 2.5 inches as it can cause stress which will further spread the disease.

If the disease is severe consider fungicides to help combat the fungus.  Check with your local cooperative extension for recommendations.

For more information on Red Thread disease please see Rutgers EDU-An Integrated Approach to Red Thread & Pink Patch Disease.

Brown Spot

Brown patch is a fungus (Rhizoctonia solani) that is common in New Jersey and can spread on all common NJ turfgrasses.  It thrives in hot weather and high humidity in the NJ summer. 

The best way to avoid Brown Patch is to water your lawn in the early morning, allowing it to dry in the sun to minimize wetness in the evening.  Cut down on your watering, watering just once or twice a week but deeply.  Overwatering will make for prime Brown Patch conditions.

Mow frequently with sharp blades for more air movement and a drier lawn.

Use moderate amounts of nitrogenous fertilizer. Over fertilizing with high nitrogen will increase the risk of Brown Patch.

If the condition worsens then consider a fungicide which can be found at your local garden center.