Utah Department of Agriculture and Food

Advice to Keep Spiders Out of Your House as the Temperature Drops

As it gets colder outside, you aren’t the only one who wants to be inside, spiders and other unwanted house guests are looking for a way inside. But what is the best way to keep them out of your house? While a lot of people spray a home barrier type pesticide, more experts, like Clint Burfitt, State Entomologist, Utah Department of Agriculture and Food, are now recommending that homeowners modify the habitat that is attractive to the insect and or spider, and using spray as a last resort. According to Burfitt, Black Widow spiders, the most dangerous spider in Utah, like dark places near the ground. Sprinkler valve boxes, firewood piles, junk piles and such are favored types of habitat. Removing or moving wood piles and other debris away from your home foundation will help. Removing vegetation from touching your home will also help keep many spiders and insects away.  Burfitt said that spider sprays are most effective when sprayed directly on spiders, rather than as a barrier. Barrier sprays work better on some types of insects, however. For more information, here are a couple of fact sheets from other states. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn74149.html

http://www.ext.colostate.edu/pubs/insect/05605.html