Yes, grass spiders are known for building horizontal sheet webs with funnel-shaped retreats on one edge. You can most often find them on dewy mornings and they are harmless, preferring to eat common lawn insects.
Grass spiders are very common in Colorado. In the fall, when cool mornings put dew on the grass, you can often find them all over the lawn. These spiders, though annoying, are harmless.
You can tell you’re looking at grass spiders because they build nests that are mostly flat except for one tube at the side. Insects walk across the sheet and the spider reaches out from the funneled side, grabs the prey, then retreats. They’re fast spiders and the whole encounter happens in an instant.
Grass spiders build low in turf and ground cover. You’d be surprised just how many can live in a small area. They’re active throughout the summer, too, but when the dew comes, it makes them more readily visible. This happens around late summer and early fall.
Grass spiders are harmless to people and pets. They don’t go indoors in great numbers and they even help by eating a substantial volume of lawn and garden insects.
If the webs bother you visually, the underlying reason for their presence often comes down to insects and irrigation. Mowing and lighter watering can help with both issues. If you start finding webs at doorways or window frames, then you may want to consider switching to warm-toned bulbs to draw in fewer insects and sealing gaps around windows and doors so spiders can’t easily get inside.
If spiders and the insects feeding them are concentrated around your house, Mosquito Squad of West Denver can help. Mosquito Squad's home and yard coverage treats the foundation, entries, and areas where spiders build. This will help you protect the spaces around your doors and windows.
