Green Thumbs Down
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.
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.