Are there brown recluse spiders in California?
No. In spite of the stories and warnings you may hear and read, the only brown recluses documented in California have been fewer than 10 specimens brought here accidentally in shipments of household goods from its native area.
The range of the brown recluse includes most of Texas, Oklahoma, Kansas, southern Iowa, most of Illinois and east to include Kentucky, Tennessee, and most of the southern states except Florida. Its range does not extend to the states bordering the Atlantic coast.
It is a small, very shy spider, about 3/8 inch long and of uniform yellowish to grayish brown color. There are no spines on the legs, only hairs that are almost too fine to see. There are no markings on the legs, but there is the “violin” shaped mark on the back. However, many other spiders have similar violin shaped marks, so this is not a reliable way to identify the brown recluse.
If you want to accurately identify the spider, you must look at the eyes. Most spiders have eight eyes; brown recluses have six.
Brown recluse bites are remarkably rare in its native range, considering that it is very commonly found in homes. The spiders live in groups, and it is common to find dozens in a home.
Rick Vetter is an arachnologist (he studies spiders) at University of California, Riverside. He writes, “One amazing story is an eighth grade teacher in Oklahoma checking up on his students avidly collecting material … on an insect collecting trip. In about seven minutes, eight students collected 60 brown recluses, picking them all up with their fingers and not one kid suffered a bite.”
Millions of Midwesterners and Southerners live with brown recluses in their houses, and it doesn’t worry them; they must think Californians are silly to be worried about a spider that doesn’t even live in California.
Many brown recluse bites result in few or no symptoms; occasionally they cause marked pain and necrosis (death) of tissue around the bite. Many other medical conditions, including tick bites and some infections, can cause similar signs.
If you want to worry about local spiders, worry about black widows. They really do live around here and are common in sheltered places such as woodpiles and under eaves.
The female is about ¾ inch long, jet black, shiny and hairless with a red “hourglass” shaped mark on her underside, while the male is a smaller, brown creature. Black widows are very shy and try to escape from humans, but they will deliver a nasty bite if grabbed.
The other spiders in El Dorado County are harmless.
If you think you have found a brown recluse, please send it to Vetter, Department of Entomology, 3401 Watkins Drive, UC Riverside, Riverside, 92521. You may bring it to your local Master Gardener Office or El Dorado County Extension, 311 Fair Lane, Placerville.
For more fascinating information see spiders.ucr.edu/myth.html.
There is no Master Gardener public education class Saturday, May 4. Instead, plan to attend the fourth annual Master Gardener Plant Sale on Saturday, May 4 in the Veterans Memorial Building parking lot, 130 Placerville Drive in Placerville, from 8 a.m. to 3 p.m.
Loads of tomatoes, vegetables, hundreds of spring/summer annuals and perennials are being sold at reasonable prices. Informational booths and Master Gardeners will be available to assist with plant selections. Cash or checks only, please.
Master Gardeners are available to answer home gardening questions Tuesday through Friday, 9 a.m. to noon, by calling 530-621-5512. Walk-ins are welcome at the office, 311 Fair Lane in Placerville.
For more information about the public education classes and activities go to the Master Gardener Website at ucanr.edu/sites/EDC_Master_Gardeners/. Sign up to receive the online notices and e-newsletter at ucanr.edu/mgenews/. You can also find Master Gardeners on Facebook.