Spiders are air-breathing arthropods that have eight legs and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms.
Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitat with the exception of air and sea colonization.
Anatomically, spiders differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax and abdomen, and joined by a small, cylindrical pedicel. Unlike insects, spiders do not have antennae. In all except the most primitive group, the Mesothelae, spiders have the most centralized nervous systems of all arthropods, as all their ganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.
Their abdomens bear appendages that have been modified into spinnerets that extrude silk from up to six types of silk glands within their abdomen. Spider webs vary widely in size, shape and the amount of sticky thread used.
Numerous species of spiders tend to be common home pests. Common types of spiders found are Cellar or Daddy Longlegs, Grass Spiders, Garden Spiders, Sac Spiders, Crab Spiders, Jumping Spiders and Wolf Spiders.
Damage/Illness caused by Spiders:
Spider bites are the most common type of problem. Most common types are non-venomous but do require first aid treatment.
Certain common household spiders spin webs above lighting units, within corners as well as in basements and require regular spider control.
Method of removal:
- Treatment first starts with a thourough inspection inside and out of the home.
- Once the problem spider has been located and properly identified treatment can begin
- If manual removal of spiders and webs is chosen, the egg sacs are disposed of with a vacuum and are sealed and dispose of in a bag immediately. If a broom is used for the removal, then it is suggested that if a spider is present on the web that an appropriately labeled insecticide be used for a quick contact kill before removal of the web.
- If chemical removal is chosen, this consists of the application of appropriately labeled dusts, wettable powders, microencapsulated, or lacquer pesticides in typical spider harborages. Perimeter treatments are helpful.
- It should be noted that interior chemical treatments are very limited. Basements that are unfinished can be treated and provide good results.
- For exterior chemical treatment, the most common type involves a barrier treatment around the base of the house and treatment under eves, overhangs, porches and decks.
- If web-building spiders are the problem, lightly dusting the web with a non-repellent dust is very effective. Control of spider insect food is desirable but will only help in long term as spiders can go for weeks or months without food.