There are about 30 different kinds of tarantulas in the U.S. Most are found in the southern states. The bite of a tarantula is painful but not dangerous. Some species have the ability to shoot hairs as a defense mechanism the hairs can be irritating. Tarantulas build burrows in the ground and then ambush prey. They will feed on any kind of insect or even small rodents.

In Iowa, these are not a realistic pest to have to deal with. If any are found it would be from a released pet or pet shop. Tarantulas are beneficial spiders in areas where they are found. Adults have been reported to live for two years or more

There are about 100 species of wolf spider in the U.S. They can be intimidating because of the large sizes they can reach, up to 35mm. usually black in color; they are also brown and spotted. Wolf spiders hunt large insects and run quite fast on the ground. They have burrows in the ground and usually leave at night to hunt prey.

            Wolf spiders can be found frequently indoors and can bite humans. They also help keep general insect numbers in check. Wood piles, underneath stones and rocks are good breeding grounds for the spiders. The large, hairy appearance is usually the worst thing about these spiders. Wolf spiders are active in day and night

Sac spiders are yellow in color and build a sac like structure where they hide in the daytime. There are only two species of sac spiders in the U.S. but it is thought that they are responsible for very high percentage of spider bites inside homes. It is not known if the bites can become serious. They are about 4-10 mm in size.

            Bites are generally when the spider is disturbed in bedding or clothing but it is thought that they will also bite when unprovoked. They will be found in corners of ceilings and walls of basements and all over the house. Sac spiders are a nuisance and should be treated with insecticides when large numbers are present in homes. They will be found outdoors and indoors throughout the season

This spider gets its name from the fact that they can jump to get to their prey. They are small about 4-10 mm. Jumping spiders have large eyes and a “fuzzy” appearance. Some have red on their back which can be mistaken for black widow markings. They are harmless to humans and can be found indoors.

            Jumping spiders do not catch prey in webs but will have small webs for protection and escape. They are unusual from other spiders in that they will be quite active during the day and love warm, sunny days. They can jump up to 20 times their body length. They can be found on cement porches, woodpiles, fences and old wood. Control is obtained through spraying

House spiders are found all over the U.S. and the world. They are the most prevalent spider in homes and structures. The webs can become a nuisance if not removed on a regular basis. They are about 5-8mm in size and are brown or black colored.

            House spiders prefer dark, moist areas with high numbers of other insects. They can be controlled with spraying and removal of webs and eggs. They are harmless to people but rather a housekeeping nuisance

These spiders are called hobos because they hitch rides with humans and transfer to different areas. They are found all over the western states but the range is spreading rapidly. It is thought that the bite might cause legions but medical research is foggy on this subject.

            Adults are 11-14mm in length and are off brown colored. They prefer dark, moist areas that are undisturbed. They are not good climbers so they are mainly found along the ground. Hobo spiders will make nests in cracks and also in the ground. Usually, the holes are surrounded by the silken web which helps catch prey. Hobos feed on other insects and other spiders. Control is the same as other spiders with spray and keeping clutter off the ground around the house. When these spiders invade homes, crack and crevice treatments are necessary. Remove webs and eggs to keep numbers in check.

There are about 20 different species of daddy longlegs spiders or cellar spiders in the U.S. They are more of a nuisance because of the immense amount of webs they produce. Daddy longlegs have long legs about 2-8mm in length and are off brown colored. They are usually found along basement ceilings and front porches.

            Daddy longlegs are harmless to people and feed on other insects and spiders. Pest control can be used to keep numbers down but homeowners can also remove webs and eggs to keep numbers down. They are the most common spider of homeowners in Iowa and many other states.

Brown Recluse spiders are also called fiddle backs. They get the name from their reclusive behavior and fiddle shaped design on their back. Adults are generally about the size of a quarter. They have long legs and hold themselves up high off the ground. Brown recluses are light brown in color. They do not make webs but prefer dark, moist, undisturbed areas like crawlspaces, attics and closets. If provoked, they will bite and it can be painful.

            There is no cure for infected areas other than removing skin and areas that are dying. If left alone, infected areas spread all over. Medical attention should be sought if bites are suspected. Outdoors they prefer shingles, unused boxes, woodpiles, or clutter in garages for shelter. Pest control is recommended for houses with these spiders.

Black Widows get the name because of the myth that females eat the male after mating. The fact is that this is very rare. Females are about ½ inch long with a red “hour glass” design on the abdomen. They are shiny black in color. Males are not a danger to humans as they do not bite. Black widows feed on other spiders and insects. Venom can be fatal but mostly in children. Widows try to avoid high traffic areas but will attack if guarding the nest or if they feel threatened. In Iowa, widows are rarely found unless brought in from other states.

Control of spiders is obtained not only through pest control but also by keeping homes clean of clutter and harbor areas. Cleaning up spider webs and food sources will help keep numbers down. Pest control will only help keep numbers down, not eliminate every spider.