How do you treat sod webworms? In this article, we’ll look at preventive and control strategies to get rid of these insects.

In spring, the indications of sod webworm feeding start to appear on your turf grass, and in a matter of days, they can take over your lawn.

In a single night, a female sod webworm can lay up to 60 eggs. This egg can hatch in just seven days, and then another sod webworm will be conceived by at least six weeks.

About Sod Webworms

Adult sod webworms are not the problem, their larvae are.

There are several sod webworm species, few of which have only one generation in mid to late summer, and do not cause significant damage.

Only the variety which has larva of the first generation in early spring causes substantial issues in turfgrass because it is only the first surge of feeding worms.

The feeding pattern of the larvae causes dead brown patches in the lawns, and most times, gardeners find the recovery of their beautiful garden quite challenging.

So when you are concerned about your damaged lawn, and you need to get rid of the cause of the damage, focus on getting rid of larvae, not adult moths. But then, to get rid of sod webworm larvae, you have to get rid of the insect also.

How to Get Rid of Sod Webworms Completely

When you spend a lot of time ensuring your lawn looks great, it can be irritating when your grass gets ruined by some pests. Sod webworms are a kind of insect that lives in turfgrass.

While the adult moths won’t harm your lawn, the larvae can be incredibly destructive, leaving large bare patches of grass.

However, you need to remove the sod webworms on your lawn first to prevent it from reproducing larvae that destroy your garden. Luckily, it’s easy to get rid of sod webworms yourself.

The following are the ways to go about it;

Water Your Grass

Sod webworm caterpillars create their webs in the dry thatch layer that forms between grass and soil. The majority of small to mild sod webworm infestations can be handled by watering the turf.

How frequently you water the lawn depends on the weather you live in. If the weather is hot and dry, you might need to water your garden for an hour a day.

Use Endophytes

Endophytes are a truly unique type of fungi living in grass. They’re not dangerous to the green, but they can repel insects like sod webworms. Sprinkle the seeds in your current plant, and water the field until the grass is rooting.

Unique grass seeds can be bought in most plant supply stores.

Follow all instructions on the same label, especially if you have livestock that will eat the grass. Excessive endophyte intake can be harmful to some animals.

Use Nematodes

Nematodes are a natural remedy for adequately disposing of sod webworm caterpillars. These microorganisms utilize the caterpillars as host, which ultimately leads to their demise. What you should do is spray them onto the grass near the areas impacted.

You can buy beneficial nematodes at any garden shop around your area, or you can place an order online. Endeavor to check the expiry date because nematodes have a brief life span.

Apply an Insecticide

You may have to use a pesticide if you notice significant grass destruction. Potent insecticides like those found to contain acephate, carbaryl, or bendiocarb are very useful.

Watering the lawn until you add an insecticide can help the pesticides reach the plant deeper.

You could either use a spray or an insecticide containing granules. When using a spray solution, add at least 15–25 gallons of pesticide per 1,000 square feet of grass for each.

When using a granular insecticide, apply it with a spreader of the fertilizer.

Follow the irrigation instructions of the label: Usually, granular insecticides are followed by approximately one hour of watering to guarantee that the granules fall into the turf.

DIY on Getting Rid Of Sod Webworm

Materials needed;

  • Dethatcher
  • Garden rake
  • Dish soap
  • Steinernema carpocapsae
  • Bacillus thuringiensis subspecies kurstaki
  • Spinosad


STEP 1: Inspect At Dusk

Adult sod webworms are quite aggressive all through warm evenings, particularly in July and August. The way they fly in the evening makes it easy for you to identify them.

So your first step towards eradicating this peat is to inspect your lawn in the evening. Whenever you notice a jerky movement of a flying insect, just assume you have an infestation of the real pest- their larvae

However, seeing a few adult sod webworms does not automatically imply that your lawn needs a chemical treatment.

STEP 2: Check For Brown Cut Patches

Check for brown cut patches on your lawn as the extent of damage will inform your next decision.

When sod webworms larvae consume your grass, you’ll start to see little spots appear. The lawn will often seem to have been cut or sheared.

Harm from the sod webworm caterpillars on one’s lawn could be up to the size of a baseball. However, if an outbreak is especially bad, these patches may connect, establishing even larger brown spots.

Due to birds searching for the webworm larvae, the brown patches can sometimes have noticeable pencil-sized holes.

Though sod webworm larvae live in the dry thatch underneath the grass, harm occurs predominantly on hard to irrigate slopes and banks.

STEP 3:  Check Your Turf For Tunnels

You need to also search your turf for the tunnels made by the larvae of this insect. More so, their wastes are green fecal pellets.

To check for the extent of the infestation, you will see silky tunnels that the real pests -worms-  build to shield themselves and their soft green fecal pellets.

If you see the above all over your lawn, just assume you have an infestation

STEP 4: Use Soapy Water To Rinse

You should rinse out your lawn with soapy water.

Dilute 1 gallon of water with two tablespoons of dish soap. Pour the mixture over 2 feet to 2 ft on the outside of the dead grass.

The soap can irk these caterpillars and push them onto the lawn floor.  And you’ll have an idea of the extent of the infestation.

Step 5: Rake or Detach Grass 

Use a garden rake to rake the lawn, but you should detach the grass if the sheet of thatch is thicker than 1/2 inches.

Set your rake to remove the stings, with your rake, and you can remove as much sting as possible or rake the lawn multiple times with a manual rake till small sting comes out of the grass.

Dethatch the yard at minimum once a year to avoid a thick layer of thatch from evolving, which is appealing to turf webworms.

Step 6: Use Liquid Soap

After detaching the grass,  you can now add a thicker soapy solution to expose the webworms.

Mix a 2 to 4 tablespoon dish soap solution with one gallon of water. Drench 1 square yard of the affected area with a solution.

Check the number of sod webworms appearing over the next 10 minutes. If more than 15 sod webworms arise during your test, the next step would be to treat the lawn.

Step 7: Apply Nematodes

The next step would be to apply Steinerneme carpocapsae nematodes to the lawn, especially if it has not been treated for over 60 days.

When you apply the nematodes at night, it will be more effective because the heat of the sun won’t be able to kill them before they work in the ground.

You should look out for the expiring date of nematodes

Step 8: Apply Bacillus thuringiensis

And if your lawn is potentially toxic to nematodes, use Bacillus thuringiensis subspecies kurstaki or spinosad on your parks and gardens.

Implement Bacillus Thuringienssis at dusk or night so that sod webworms can receive direct dusting from their dens when they emerge; reapply weekly as required. Apply spinosad at whatever time of day, as the formulations vary according to the package directions.

When you discover this pest on your lawn, the first thing you should do is water and fertilize regularly to improve the grass’ health and to enable it to grow.

Also, make sure that you don’t use full spectrum lawn insecticides that can kill beneficial pests. During the early appearance of the larva, you may also spray the lawn with Bacillus thuringiensis (although it has little control over older larvae).

And then, if you must use an insecticide, make sure you use the one that is specifically designed to get rid of sod webworms.

More importantly, eradicating sod webworms effectively with chemicals implies that you sprinkle the compound in the late afternoon to ensure poison intake.

If sod webworm infestation is rampant in your area, you might want to use a worm-resistant turf grass. Any “endophyte enhanced” green, such as certain tall fescues, perennial ryegrass, and fine fescues were already designed to resist the pests.


The damage on your lawn is mostly caused by sod webworm larva, not the insect itself. Therefore you should concentrate efforts on getting rid of the worms first and then sod webworm to prevent it from reproducing more larvae.

The initial signs of sod webworms feeding are noticed during spring. The nibbling exercise of the worms eliminates the tender top growth of the grass and leaves thin patches of shorter grass behind them.

As they develop, the webworms trigger brown sod to larger areas. These typically occur in sunny locations and dry spots like the driveways and curb edges.

So pay a little attention to your lawn to prevent the pest from ever showing up. More so, watering your lawn regularly can prevent sod webworms from appearing in your yard.

This guide explains in detail how to get rid of sod webworms completely.

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