Sod Webworm Control: How To Get Rid of Sod Webworms

This page is a general DIY article on eliminating sod webworms from your property by using the products and methods suggested throughout this guide. Follow this DIY guide and use the recommended products, and we guarantee 100% control of sod webworms from your property.

Sod webworms are notorious for invading lawns and damaging turf and plants. Also known as turf webworms, sod webworms are the larval or caterpillar stage of the small white-brown moth. They are about 1 inch long in this stage and can be found munching on blades of grass in a yard.

These lawn pests typically become a problem for cool-season turfgrasses in the fall. Signs of Sod Webworm damage come in the form of brown patches of dead grass where they have been focusing their feast. Sod webworms overwinter and then emerge in the spring with a big appetite.

While sod webworms are harmless to humans, they are damaging to lawns. If you have an infestation of these caterpillars, they will do a number on your lawn unless you intervene.

By following our professional DIY guide, you can get rid of a sod webworm infestation yourself. Arm yourself with the products we recommend and follow our step-by-step directions to eliminate a sod webworm invasion quickly and affordably.

Identification

Before carrying out a treatment program, you need to make sure that you properly identify the pest to be a sod webworm. Misidentification can lead to using the wrong pesticides and not getting the desired result in eliminating the pest.

• Sod webworms are the larval stage of a species of moth from the Crambus genus. When they are in this caterpillar stage, they are about 3/4 of an inch long with tan, grayish brown, or light green bodies with dark spots. They also have a dark head capsule.
• There are about 20 different species of sod webworm, and they are known for having large appetites in the early larvae stage and are very destructive to lawns they are found in. As adults, they don't feed on grass, but seeing active moths in the area makes it likely that eggs are nearby.

Use the description and image above to determine whether the pest you are encountering is a sod webworm. If unsure, contact our experts; we will help you identify the correct one.

Inspection

After you have correctly identified the pest on your turf to be sod webworms, you can then move forward with an inspection. 

Where To Inspect

You will be primarily inspecting your lawn to see if there is any evidence of an active infestation, usually wherever there are discolored or brown patches of lawn. When the sod webworms are inactive, they will hide in silk-lined burrows in thatch and soil.

You can flush them out and check if they are present by using a soapy water solution and pouring it over about a square foot of your turf. After the solution soaks for a few minutes, check to see if sod webworms are floating on top of your grass. If you see over a dozen of them, assuming you have an infestation that should be treated would be safe.

What To Look For

You should be looking for active sod webworms as well as grass damage inflicted by the pests. Sod webworm damage can appear similar to a turf disease with discoloration of grass and spots of dead grass.

Timing is important when treating sod webworms. These bugs are known to lay many eggs, and it would be best to control them before they hatch, which adds to the damage.

Treatment

Once you have completed the inspection, you should prep your lawn for chemical treatment. Before applying chemicals, we recommend wearing personal protective equipment to keep yourself safe.

Since they are called sod webworms, it would be wise to focus applications on your lawn. Multiple generations of sod webworms occur throughout the year, with one forming in the spring and the second generation showing up in the fall.

We recommend Supreme IT and Valar Plus Bifenthrin Granules because they kill infestations quickly upon contact and have a long residual effect. This combination delivers a solid 1-2 punch of surface and subsurface control.

Step 1: Apply Valar Plus Bifenthrin Granules to the Lawn

Valar Plus Bifenthrin Granules is a granular insecticide that is labeled to control many turf pests, including sod webworms.

Start by first calculating the square feet of your lawn or treatment area to determine how much Valar Plus can be used. Do this by measuring your lawn's length and width in feet and multiplying them together (length x width = square footage).

To treat sod webworms in your lawn, apply Valar Plus Bifenthrin Granules at a rate of 1.15 pounds per 1,000 square feet.

We recommend applying the granules using a push broadcast spreader. You can also use a hand spreader for smaller patches of lawn.

Load your spreader with the proper amount of Valar Plus Bifenthrin Granules based on your square footage. Broadcast half the granules in parallel lines once across the area and then at a perpendicular angle (like a grid pattern) the second time around so that the granules are evenly distributed over your entire lawn.

Once Valar Plus Bifenthrin Granules has been applied, it should be activated by water or a liquid concentrate. Supreme IT will do this in the next step.

Step 2: Mix and Apply Supreme IT to the Lawn

Supreme IT is a broad-spectrum insecticide that is labeled for treating sod webworms. This product doesn't only activate the Valar Plus Bifenthrin Granules. Still, it will also kill sod webworms exposed to the product along with a long residual effect that continues to kill for up to 90 days after application.

To apply Supreme IT, mix it with water in a handheld pump or hose-end sprayer. 

Apply Supreme IT at a rate of 0.18 to 0.25 fl. oz. per gallon to cover 1,000 sq. ft.

You may have to apply a higher rate of 1 oz. per gallon if you have grass taller than one inch or if there is a severe infestation.

We recommend using a 20-gallon hose-end sprayer for a more thorough and easier broadcast application of the insecticide. Make sure the sprayer's control valve and water pump are off, and then attach the hose-end sprayer nozzle to the hose. Remove the reservoir from the nozzle and add the proper amount of Supreme IT and water.

When adding the product to the reservoir, plan to use 2 gallons of water per 1,000 sq. ft. Double-check that the water is still off, reattach the reservoir to the nozzle securely, and begin spraying by pushing forward on the control valve after turning the water on to the hose.

Broadcast the Supreme IT evenly over your yard and garden rather than spot-treating. Use a fan spray setting to get nice uniform coverage.

Reapplication may be necessary until you no longer see sod webworms present. Apply later in the day as sod webworms are most active at night time. We then recommend irrigating lightly with water (1/8 of an inch).

Prevention

After eliminating sod webworms, you will need to take preventative measures with your property to prevent future infestations completely.

• The best way to prevent sod webworms from returning after you've eliminated them with insecticides is regular lawn maintenance. Keeping your lawn healthy with routine mowing, watering, fertilization, and aeration can deter certain bugs and help your lawn overcome others.
• Rake your lawn regularly to remove thatch and expose the sod webworm to its natural predators. Give your lawn 1 to 1.5 inches of water once a week, and mow your grass at 3 to 4 inches to encourage root growth. It would be best if you fertilized regularly to ensure your turf gets the nitrogen nutrition it needs to fight against pest symptoms.
• Finally, periodic reapplication of Supreme IT and Valar Plus Bifenthrin Granules should be done as a preventative measure to further discourage sob webworm activity.

Key Takeaways

What Are Sod Webworms?

• Sod webworms are a destructive turf insect on residential lawns and commercial landscapes. Damage from sod webworms initially goes unnoticed by lawn owners, but once they multiply to a sizable population, the damage becomes very obvious.

How to Get Rid of Sod Webworms

• Our top recommendation for sod webworm control is Supreme IT and Valar Plus Bifenthrin Granules. Broadcast both products over your entire lawn.

Preventing Sod Webworm Reinfestations

• To prevent reinfestations of sod webworms, keep up with regular lawn maintenance, and apply Supreme IT and Valar Plus Bifenthrin Granules preventatively every 3 months.