Prevent Sod Webworm Next Year

Create Diversity
It is a good idea to encourage the many insects and animals living in your yard that normally prey on lawn pests. These natural predators come in all shapes and sizes. While many are insects themselves, others are microscopic organisms, amphibians, or birds. The more of these different kinds of predators live in your yard, the fewer pest insect problems you will have. They will take up residence in a yard that includes their favorite plants and other foods. The greater the variety of plants on your property, the greater will be the diversity of natural enemies of sod webworms that will be attracted to it.

Get Rid Of Thatch
Sod webworms often infest lawns that have a serious thatch problem. Thatch is not caused by grass clippings. Thatch is an accumulation of dead roots, dead grass plants, and other debris that is usually caused by compacted soil. By removing thatch thicker than ¾ inch with a dethatching_rake or a motorized dethatching machine, you can generally reduce a serious webworm infestation. To keep the lawn healthy and control thatch, aerate the lawn using a lawn_core_aerator [741 500] at least once, preferably twice, a year. Add about a 1/4 inch layer of organic material such as peat_moss , composted municipal sludge (such as Milorganite), or sifted compost each year to virtually eliminate thatch buildup.

Click here for more information about Controlling Thatch .

Keep The Lawn Cool
Because webworms prefer turf that is dry and warm, do not allow your lawn to get too dry in the hot summer months. Water it well when rainfall is sparse. Watering in the late morning provides moisture to the grass and also keeps the soil surface cooler, making the area less attractive to webworms. Cut the grass no shorter than 2 inches. Longer grass blades shade the soil and keep it cool.

Click here for more information on Watering Lawns

Mow The Lawn Properly
Your grass will be healthier and look better if you mow the lawn lightly and frequently. Research shows that light, frequent mowing is less stressful to grass plants than heavy, infrequent mowing. Mow every 5 days during the cooler spring months when the grass is growing rapidly, then slowly change over to every 7 to 10 days when hot weather slows down grass growth. In summer drought periods the lawn may not need mowing for several weeks. Resume more frequent mowing in the fall.

The height of the cut is critically important to a healthy lawn. Small changes in mowing height make a big difference in lawn health and vigor. Increasing the height of your grass only 1/8 inch creates about 300 square feet of additional leaf surface for each 1,000 square feet of lawn. Because the leaf blade is the grass plant’s food factory, the increased surface area allows more photosynthesis to take place, contributing to stronger grass growth. Conversely, shearing grass too close to the soil reduces photosynthetic activity, leaves less leaf area to shade out weeds, and exposes the lawn to greater stress from heat and drought. Click here for more information about Mowing Lawns . Click here for more information about Choosing A Lawn Mower .

Attract Beneficial Insects To The Yard
Several beneficial insects are known enemies of sod webworms. Braconid wasps (Apanteles spp.) , vespid wasps (such as yellowjackets), earwigs, ground beetles and rove beetles, certain flies, ants, spiders, and mites all attack webworms at various stages of development. Research indicates that these natural predators will consume at least 75% of sod webworm eggs within 48 hours after they’ve been laid by the moths.

Encourage the natural predators of sod webworms to stay in your yard by providing them with a tempting variety of their favorite plant sources of pollen and nectar. One product, Border Patrolä, is a mix of insectary plants particularly attractive to beneficial insects, and includes evening primrose (Primula), wild buckwheat (Eriogonum), candytuft (Iberis), baby blue-eyes (Nemophila Menziesii), bishops flower, black-eyed Susan (Rudbeckia hirta), strawflowers, nasturtiums (Tropaeolium), angelica, and yarrow (Achillea).

Feed Birds Year Round
Next to beneficial insects, songbirds consume the most pest insects in your yard. Robins, blackbirds, flickers and starlings will eat a lot of webworms if they are in your lawn. Many seed-eating birds prey on caterpillars while raising their young. Encourage birds to settle in or near your yard and prey on fleas by offering them food, water, and shelter. See Attracting Birds for more information about this activity.

see all questions...

Do you have a gardening question? Ask Nancy