Webbing on shrubs

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To dealing with funnel weaving spiders as a pest problem.

(Other webbing, unlike this photo...)

Such spiders are not dangerous. The visual distraction is outweighed by the pest  control they provide. Sweep the webs away before parties if you don't want them seen.

Please don't let anyone talk you into spraying for them because anything that kills them will kill other predators of insects. (You'd be amazed how many predators can inhabit one small portion of a shrub just like the one in this picture.) Losing the predators can really tip the balance in favor of the pest insects.

Quite a few spider species make webs that stretch across shrubs and other vegetation -- even across grass tips. Some create a funnel-shaped retreat at one edge where they lurk. Thus some are called "grass spiders," others "funnel weavers." One group of very tiny sheet weavers are called dwarf spiders.

Webs on shrubs may be quite visible on dewy late summer mornings. If they look like these they are nothing to worry about. If there is a funnel shaped cavity near one edge, they are probably the work of funnel weaving spiders that can be a pretty important part of a natural pest control program.

Webs on shrubs may be quite visible on dewy late summer mornings. If they look like these they are nothing to worry about. If there is a funnel shaped cavity near one edge, they are probably the work of funnel weaving spiders that can be a pretty important part of a natural pest control program.

They catch a lot of small insects that might otherwise feed on young plant shoots.

They catch insects that occur in annoying "hatches" including various gnats and mayflies. (If you live near water where many such hatches occur, you may see more webs than gardeners further inland, yet these spiders do occur all over the continent.)

They're unlikely to become a house pest. As the weather cools in fall some may move inside buildings but can't live there successfully and so die out.

They're not aggressive to people.

Right: When our kids were very young and Steven was home with them full time, the three of them spent a memorable afternoon catching insects and tossing them into a funnel weaver's web on one of our dwarf Alberta spruces. Two of the conclusions they came to then: One, the spider was not choosey but willing to eat any insect that hit near the web's center. Two, it was shy. It would rush out and grab any insect as long as Steven and kids were not in plain view. It remained in hiding in its funnel unless they stepped back.

An additional conclusion made now, 30 years later as we observe the spiders still occupying the same shrubs: They are self-limiting, never having been much more numerous than what you see here.

To learn more, search Agelenopsis, Hololena, Tegenaria, Linyphiidae. Avoid scare stories that proliferate in the sensationalist news and gossip channels about nightmare spiders of Australia or Asia ; stick to information from North American.edu publications such as Spiders Commonly Found in Gardens and Yards and from non-commercial naturalists networks such as Bugguide, hosted by University of Iowa Entomology.

Other webbing

If the webbing is draped across a sizable bit of a tree or shrub, look into

If it encases a crotch in a crabapple or fruit tree, chalk it up to eastern tent caterpillar.

 

Related links

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  • Funnel spider at work