Do Black Widows Live in Ivy?

Meet the Widow

• Before you reach into that overgrown English ivy in your landscape or clinging to your home, put on some gloves. Female black widow spiders, which have shiny black bodies with a red hourglass-shaped marking on the abdomen's underside, can reach about 1/2 inch long not including the legs, and they love to cram into tight, protected spots under dense vegetation or inside cracks in walls. In late summer or early fall, you may notice the black widow's white to cream-colored egg sacks before you see her. Normally, black widows are very docile and skittish, but when they're guarding egg sacs, bites are much more likely.

Removing the Welcome Mat

• Black widow spiders are a conundrum for many people -- on one hand, they provide a useful service by consuming pest insects, but on another, their bites can be dangerous. Having these potential hazards near homes is unacceptable by most people's standards. Discourage the spiders by removing or drastically thinning ivy on homes and in gardens, dealing with insect infestations that may be keeping them fed and keeping any kind of debris, construction materials or firewood far from your home. If black widows are near your porch, replace the outdoor bulbs with yellow bug bulbs to reduce the number of prey insects that congregate at night.

To Spray or Not to Spray

• Chemical control for spiders is largely ineffective; most of the chemicals available to the typical homeowner must be sprayed directly on the spider for them to work at all. If your home's landscape is badly infested with black widow spiders, to the point that chemical treatment is the only option, contact a pest control expert. For smaller infestations, crush the spiders you find with a rolled up newspaper and scrape egg sacs into a bucket of soapy water. Always make sure you're wearing gloves, long sleeves and pants when dealing with black widows.

Once Bitten, Twice Shy

• Adult female black widow bites are the stuff of legend, though estimates indicate only 1 to 5 percent of bites are fatal. The neurotoxin alpha-latrotoxin is the primary compound in black widow venom; it can cause flu-like symptoms within three hours of a bite. Gradually other symptoms like fever, chills, nausea, burning sensations, difficulty breathing or constipation may appear, gradually clearing within four days. Bites swell very little, but a rash may develop around a pair of red fang marks. Even though bites aren't necessarily fatal, they should be considered a medical emergency.