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Sod Webworm

Sod Webworm: What are the Treatments and Prevention of Sod Webworm

Sod Webworms are moth larvae (caterpillars) common to Australia, Asia, central and northern Africa, and certain Pacific Islands. Sod Webworm was formerly thought to be an occasional pest of turfed grounds, but it is now recognized as a severe pest of warm-season turfgrasses, particularly during the warmer months. All of the harm is caused by the larvae (caterpillars). Several kinds of sod webworms, sometimes known as “lawn moths,” infest home gardens. The larvae can cause significant harm to residential turfgrass. The silver-striped sod webworm, bluegrass sod webworm, and bigger sod webworm are among them.  

What Causes Sod Webworm?

Sod webworms moth larvae (caterpillars) feature rows of dots on their bodies and are pale green to light brown in color. They get their name from the web-lined tunnels where they hide throughout the day. Adult moths have white or brown wings that wrap around their bodies and snout-like projections on their heads. Adult moths rest by folding their wings back tightly against their body, giving them an extremely thin look. Adult moths’ range in length from 1/2 to 3/4 inches. They deposit their eggs on the grass and are active in the springtime and mid-summer. Young larvae are brownish to grey in color, with black markings and a blackhead when fully developed. They are 3/4 to 1 inch in length. In the spring and early summer, they are most active.

What are the Warning Signs and Symptoms?

The adult moth will emerge after 10 to 14 days. Although the adult form of this bug is innocuous, the larval stage may do serious damage to the grass. Early-season species have been shown to inflict the most harm since they have more time to proliferate and destroy a lawn. The sod webworm moth does not harm the lawn. At night, larvae eat grass leaves and stem near the soil surface. Sod webworms attack most turfgrasses, including bluegrass, bentgrass, tall and fine-leafed fescues, and buffalograss. On grass infested with sod webworms, little brown patches appear over time.

How to Get Rid of Them: Treatment and Control

Well-maintained turfgrass is generally immune to webworm damage. Mow the lawn on a regular basis. Overfertilizing the grass with nitrogen can encourage grass growth and the development of thatch near the soil. Increased grass growth and thatch buildup can lead to more sod webworm attacks in the future. Insecticides can be used to kill insects while they are still tiny and susceptible. The insecticide should be applied to your infected lawn in the early evening. This is the most active period for larvae to attack. Watering your lawn properly may make it healthier, which helps to keep webworms at bay. Lawns should be watered frequently, and thatch and other horticultural stressors should be avoided. For minor to moderate infestations, apply a soap drench on the grass surface to attract caterpillars.