Webworms: How to Identify, Treat & Prevent Them on Your Trees and Lawn Insects, Mites & Diseases Lawn Care Submitted by Elisa Edelstein If you look at the tips of your tree branches and see them wrapped in silky, white webs, you are likely seeing the work of a fall webworm. This common native insect builds protective nests that can span several branches. While webworms are a tree condition, the second type of webworm, sod webworms, quietly munch on lawns. Homeowners often lump several web-building or leaf-chewing pests together, so this guide covers both the fall webworm that targets trees and the sod webworm that damages lawns. What are webworms? Webworms are the larval, or caterpillar, stage of certain moths, and the name covers two easily confused insects. The fall webworm (Hyphantria cunea) is a tree-dwelling caterpillar that spins webbed nests around foliage, while the sod webworm (Herpetogramma phaeopteralis) is a lawn insect whose larvae feed on the grass blades and crowns at the soil's surface. Knowing which one is on the property is the first step toward treating the condition properly. Fall webworms vs. sod webworms: key differences The clearest difference between these insects is where they live and how they feed. Fall webworms are a tree condition, wrapping leaves and branch tips in loose silk tents from midsummer through fall. Sod webworms are lawn critters, chewing grass and leaving thinning, brown patches behind. Fall webworms are highly visible in the canopy, and sod webworms often go unnoticed until turf damage appears. Webworms vs. bagworms vs. eastern tent caterpillars It is easy to mistake webworms for other web-building insects. Bagworms create small, cone-shaped bags made of plant material that hang from branches like ornaments. Eastern tent caterpillars build dense, triangular nests in the crotches of branches in spring, whereas the fall webworm forms loose webs at the ends of branches later in the season. Correct identification ensures you choose the right control method for effective treatment. How to identify webworms Spotting early signs of webworms on tree limbs or in your turf lets you act before damage spreads. Each insect leaves different clues that help you tell them apart. Signs of fall webworms in trees: silky webs at branch tips The most obvious sign of a fall webworm infestation is the silky, gray-white webbing enclosing leaves at the tips of branches. Inside the web, you may find pale, hairy caterpillars alongside skeletonized or chewed leaves. As the larvae grow, they expand the nest to cover more foliage. These webs are typically most visible from late summer into early fall. Signs of sod webworms in lawns: brown patches & chewed grass Sod webworms show themselves through irregular brown patches and thinning grass. You may notice chewed or notched blades near the soil line, small green pellets (frass), or tan moths flying in a zigzag pattern over the lawn at dusk. Pulling back damaged turf can reveal the larvae and silk-lined tunnels just below the surface. Which trees and grasses webworms target most Fall webworms feed on more than 100 species of deciduous trees, with pecan, walnut, hickory, birch, and fruit trees among their favorites. Sod webworms prefer cool-season grasses such as Kentucky bluegrass, fescue, and ryegrass, though they also attack warm-season lawns. Stressed or newly established plantings tend to face the heaviest pest pressure. Are webworms harmful? Understanding the damage Why fall webworm damage usually looks worse than it is Although the nests can look dramatic, the fall webworm rarely causes lasting harm to an established, healthy tree. Because the caterpillars feed late in the growing season, mature trees have already stored most of the energy they need for the year. The foliage lost to feeding has largely finished its job, so the tree typically recovers without any treatment. When webworms become a real threat (young, stressed, or repeatedly infested plants) Webworms become a real concern on young, newly planted, or already stressed trees that cannot afford to lose leaves. Repeated infestations year after year can weaken a tree over time, and heavy sod webworm feeding can kill sections of an unhealthy lawn. In these cases, professional insect and mite management helps prevent long-term decline. How to get rid of webworms in trees If you are wondering how to get rid of webworms in trees, several effective options exist, ranging from simple hand removal to professionally timed treatments. Removing webs by hand and pruning For small, reachable nests, the easiest approach is to remove them. Use a pole or a gloved hand to pull down the webbing, or prune out affected branch tips and dispose of them. Avoid burning nests in the tree, as this damages living wood. Removing webs early, while colonies are still small, keeps a minor problem from spreading. Biological & targeted treatments and correct timing When populations are large, targeted treatments work best. Bacillus thuringiensis (Bt), a naturally occurring soil bacterium, regulates young caterpillars while sparing beneficial insects. Horticultural oils and selective insecticides also work well when applied early, before larvae mature and webs thicken. Timing is critical, so treatments should target the earliest larval stages for the best possible results. When to call a Certified Arborist Professionals should handle large trees, high nests, or recurring infestations. Our ISA Certified Arborists can identify the insects, assess overall tree health, and apply properly timed tree disease treatment and insect controls that protect your landscape and the surrounding landscape. How to get rid of sod webworms in your lawn Getting rid of webworms in the lawn starts with strengthening the turf, then adding treatment only when needed. Cultural lawn care: watering, mowing & thatch management A dense, well-maintained lawn resists sod webworms far better than stressed turf. Water deeply but infrequently, mow at the correct height for your grass type, and reduce excess thatch that shelters larvae. Overseeding thin areas and fertilizing appropriately help grass outgrow minor feeding damage and recover more quickly. Professional lawn treatment options When damage is widespread, professional treatment offers reliable control of grubs and damaging insects, including sod webworms. A lawn care specialist can confirm the condition, apply the right product at the correct life stage, and recommend a treatment program that keeps your turf resilient season after season. How to prevent webworms Keeping trees and turf healthy and stress-free The best defense against webworms is a healthy landscape. Trees and lawns that receive proper watering, mulching, fertilization, and pruning are better equipped to withstand insect pressure and bounce back from feeding. Reducing stress from drought, compaction, and improper care makes your plants less enticing to insects. Seasonal monitoring and early detection Regular monitoring catches problems while they are still small. Inspect branch tips in mid to late summer for the first signs of webbing, and watch for browning or moth activity in the lawn. Early detection means you can remove a nest or treat a small area before an infestation takes hold. Protecting your landscape Webworms may look alarming, but in most cases they are a manageable, seasonal nuisance and not a serious threat. Whether you are dealing with the fall webworm in your trees or sod webworms in your lawn, the keys are correct identification, timely removal, and a consistent focus on plant health. With the right approach, your landscape can withstand these insects and stay vibrant. If you are unsure how serious your infestation is, or you simply want expert eyes on your trees and turf, our team is here to help. Schedule a free consultation with a SavATree ISA Certified Arborist to get a customized plan to treat and prevent fall webworm and other common landscape insects. Contact us today to schedule a consultation with an expert arborist.