Household Spiders

Many species of spiders are common household pests. Although they are undesired in homes, spiders are considered beneficial because they feed on other insects. Spiders found around the home can vary greatly in size and colorations.


The vast majority of spiders in the U.S are not normally aggressive and can be provoked to bite only under certain circumstances such as feeling threatened. Most spiders encountered by people pose no danger at all.

Spider Bites

The reactions people experience following a spider bite are more often due to the foreign proteins of the saliva and not to the venom of the spider.

Reaction can vary from mild to severe. If you experience a severe reaction, consult your physician.

Where Found

Outdoors, spiders are commonly found under buildings, rocks, woodpiles, basements, and inside meter boxes.

They may be also found in stacked patio furniture, small cervices, around the foundation of the home, garages, and storage sheds. Indoors, they may be found on flooring, walls, in closets, cupboards, and under furniture.

Black Widows

Black widow spiders are shy and nocturnal in nature. Adults are a shiny black, with a red design on the underside of the abdomen resembling an hourglass. Body size ranges from ¼ to ½ inch long. Both the male and female measure ½ -2 inches when the legs are fully extended.

Black widows like to build their nests in dry and protected locations. Outdoors they may be found in dark hidden corners near the floor and not high in the light where most webs are seen.

The black widow produces a powerful venom that is neuro-toxic (affects the nerves). Within a half hour, a sharp pain develops at the site of the bite. This pain is the prime symptom. The pain may gradually move on to other parts of the body including the abdomen and legs. This pain may last 12-48 hours. Other symptoms can include sweating, fever, increased blood pressure, difficulty breathing, and nausea. Consult your physician if a black widow spider bite is suspected. Particularly at risk are the very young, the elderly, and sick or hypertensive persons. In most cases, the reaction to a black widow spider bite is no worse than a bee sting.

Preventative Measures

Indoors: Do regular vacuuming of rugs and cleaning of floors and basements; particularly in bedrooms, closets, storerooms, and where children play.

Shake out clothing and blankets that have been sitting at ground level overnight.

Outdoors: Weather strip doors. Seal cracks and crevices around windows and doors. Repair any broken foundation, window, or door screens.

Wear gloves when working in areas that have been undisturbed for a long time.

Trim shrubbery away from windows and other points of entry.

Eliminate places for spiders to build their webs. Keep yards free of trash and other accumulations of debris.

Chemical Control

Most spiders do not need to be controlled with pesticides unless they have become a problem in the home. Garage and outdoor areas can be sprayed with available over-the-counter liquid insecticides according to labeled directions.​

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