T ry to relax it's only a by Ruth O’Neill, Insect Diagnostician MSU Schutter Diagnostics Lab

Do you sometimes have the feeling In spite of the challenges, the that are more abundant “long-bodied cellar spider”, a in your house in the fall? There gangly species native to warmer are probably several reasons for climates, has adapted to survive ( TENG aria ) by istockphoto.com this. One is that some spiders do and reproduce in human living move indoors while seeking mates. quarters in temperate zones. Jumping Spider close-up by sam martin And don’t forget that you are also They commonly occupy tangled spending more time indoors and so Jumping Spider by sam martin webs in corners on ceilings, are more likely to notice them. But for some spiders, their where their drab spindly profile makes them easy to sudden “appearance” may be an illusion - they actually overlook and thus less likely to annoy people – an important were in your house all along, but were inconspicuous when quality for survival. Long-bodied cellar spiders look so they were younger and smaller. Some spiders are actually delicate that a breath of air might knock them apart, yet best-adapted to living and reproducing indoors, and would they are efficient predators on flies, mosquitoes, and other fare poorly if evicted from the house. spiders. Because of their appearance they are sometimes mixed up with “harvestmen” which are not spiders and Spiders trying to carve a niche for themselves indoors do not make webs. To add to the confusion both are often doubtless find humans to be very difficult roommates at called “daddy-longlegs”. best, as most people have a low tolerance for them. Fear of spiders, arachnophobia, is among the most common of Jumping spiders are also common in and near houses. They phobias. Of course, what we mainly fear are their bites. do not build webs at all, though like Spiderman, they do Nearly all spiders do produce venom, a necessity for produce silk lines that they use as tethers when they leap subduing prey. However, few spiders are really harmful from place to place covering distances many times their as they seldom bite unless provoked and do not deliver own body lengths. A common species in our region and significant amounts of venom even when they are able to across the U.S. is the “bold jumping spider.” This active penetrate your skin. One genuinely dangerous exception hunter is a large, alert black-and-white species that often in our region, the “western black widow spider”, is works in window areas, using its excellent binocular vision occasionally present in outbuildings and garages, but they and quick reflexes to stalk flies and other insects trapped rarely enter houses. Perhaps the most feared species of against the window glass or screening. Many other jumping all in the U.S., the “brown recluse spider”, does not occur spiders have brilliant markings of red, blue, yellow, or anywhere in or even near Montana – a fact that should put green. many suspicions to rest. There are three funnel web spiders of the genus that are commonly encountered in houses. All share a similar appearance, having brownish-yellow coloration

Jumping Spider by sam martin T ry to relax

How to Keep Spiders Out: • Move firewood away from the house and check it before bringing inside. • Keep grassy or weedy areas near buildings cut short. • Trim back shrubs and other plants that directly and a mottled chevron patterning on the abdomen. The contact your house. domestic house spider () and the giant • Put in weatherstripping or caulk to seal gaps around house spider (T. gigantea) are native species, both true the foundation and ground level windows. house spiders that are seldom found outdoors. The third • Install door sweeps. species, a non-native of increasing concern in recent years, • Check to be sure screens fit tightly, and check for domestic house spider ( T egenaria) by istockphoto.com is the “hobo spider” (T. agrestis), sometimes erroneously tears and holes. called the “aggressive house spider”. Hobos typically live • Stuff rags around pipes where they penetrate walls and breed outdoors, but males often wander into houses or floors. while seeking mates. Hobos are sometimes suspected of • Sticky traps can be used to capture spiders possessing highly toxic venom and an aggressive nature, wandering on floors. yet there is increasing skepticism among spider experts about the danger this species poses. However, until more data on toxicity is in, caution is still advisable around this spider and it should be removed or killed when encountered in houses. The three species can only be reliably identified by expert examination of minute anatomical structures.

When spiders are to be removed from dwellings, it is often most practical to either crush them or trap them for removal outdoors, rather than resorting to household pesticides. Many spiders can be tolerated indoors and even appreciated for the pest-control services they provide. 

Jumping Spider by sam martin

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