There are over 35,000 species of spiders all over the world. We cannot begin to cover all of them. We will only cover four of them that are commonly found in houses in the United States. Other species of spiders can usually be handled the same way as these ones are.
These spiders will spin an irregular shaped web and hang from it in an inverted or upsidedown fashion. The web is used to ensnare its victim. They are usually found in seldom used parts of the garage, basement, or crawl spaces.
- Size: Female about 1/2 inch high, a nearly spherical body of about 1/4 inch in diameter, and total length, including legs, of about 1 1/2 to 1 3/8 inch long. Males are about half the size of females.
- Color is typically black with two red triangle marking usually joined to form an hourglass shape.
- Young spiders primarily orange and white but acquire more and more black as they grow.
- Distribution: Most species in the United States are found in the southern and western state, with one, the northern black widow, being found more in northern states and Canada.
The black widow's venom is a neurotoxin. Although the bite is rarely felt, about 2-3 hours afterwards, the area reaches its maximum swelling and will stay swollen for 12 to 48 hours, and then gradually subsides. The major symptoms are increased body temperature, increased blood pressure, profuse sweating, and nausea. There is an antitoxin available from a physician.
Inside the home, brown recluse spiders can be found in almost any undisturbed area to which they can gain access. They are most commonly found in boxes, among papers, and in seldom used clothing and shoes, although they can be found in corners, underneath tables and chairs, or in crevices such as those found along baseboards, doors, and windows moldings. Therefore, homeowners should be careful in storage areas such as closets, attics, bedrooms, crawl spaces, and basements. In commercial buildings, common places to find these spiders are in heat tunnels, boiler rooms, attics, basements, storerooms, and garages.
- Size: About 1/4 to 1/2 inch in body length.
- Color is tan to dark brown with a darker fiddle-shaped marking on the top of its cephalothorax.
- Distribution: Most species found in the southwestern states, with one found in Massachusetts, one ranging from New York to Illinois, and one in the eastern United States.
The female will spin an irregularly shaped web. This web is not used to snare prey but is used as a place to retreat to.
Both male and female brown recluse spiders can inject venom from their bites. This venom is causes an ulcerating type sore to appear. Other symptoms include restlessness, fever, and difficulty in sleeping. The damaged tissue typically falls out, exposing an open ulser and possibly exposing muscle and bone. Healing is very slow and can takes weeks. There is NO antitoxin available yet. Go to the emergency room or to a physician immediately if bitten.
Inside structures, house spiders are most likely to be found in upper corners, under furniture, in closets, angles of window frames, basements, garages, and crawl spaces. Because their web selection is by trial and error, they tend to leave many webs within a few short days. Dust collecting on these webs allows them to be easily seen. This is the most common spider found in homes and is found throughout North America.
- Size: Adult female about 3/16 to 5/16 inch long, with the male slightly smaller
- Color is highly variable depending on the specific species and geographical area
Wolf spiders actively hunt during the night, but will occasionally hunt during the day. They are fast on their feet and will usually pursue their prey. They often seen by humans and usually alarm them because they are big, hairy, and fast.
- Size: Female about 3/8 to 1 3/8 inches long; Male about 1/4 to 3/8 inch long
- Color is usually dark brown, often with paler stripes or markings
- Eyes: Eight dark eyes
- Cephalothorax and abdomen are very hairy
- Legs are long and spiny
Outside, they are usually found under stones, landscape timbers, firewood, under decks, in leaf piles, etc. Although they sometime enter structures, they are usually not permanent residents. They usually enter from firewood or while pursuing prey.
SPIDER INFESTATION MANAGEMENT
|Spider management takes on several steps. They include: |
- Inspection to determine where the spiders are located
- Indentification of the spiders will help to tell where their harborage locations are
- Prevention consists of making sure the building is in good physical condition and properly screened and sealed to prevent entry. Also, reduction in conducive conditions for insects will reduce the potential food possiblilities for spiders.
- Sanitation practices consists of keeping the premises free of debris such as boxes, papers, clothing, lumber piles etc. It is wise to wear protective gloves when cleaning out clutter and debris. Outside, remove debris, firewood, and lumber piles, landscape timbers, and stones, etc. away from the structure. Keep grass mowed to less than 3 inches and trim any vegatation away from structure.
- Mechanical removal of the spider, webs, and egg sacks by a vacuum is essential. Seal and dispose of the vacuum bags immediately.
- Pesticide applications do not tend to work well with spiders because their contact with surfaces tends to be minimal. However, continual spraying may reduce the existance of the spiders.