Spiders Ė The Natural Bug Magnets

Kay Hinkle
Adams County Master Gardener in Training

Iíll admit Iím not a fan of creepy-crawlers in my house. Other than moving a grand-daddy long legs spider from inside the house to outside, I would never get up close and personal with arachnids by choice. I know they wonít hurt me, but all the many legs and eyes on a sometimes hairy body can certainly be intimidating.

What I love about the arachnid, in spite of its appearance, is that it is on a mission to eradicate the very pests that I want to get rid of. It is truly a win-win situation to have spiders in the garden, and yes, even in the house as long as they stay hidden and out of my way. First, letís talk about common household spiders and their webs.

Cobweb spiders (over 2200 species) are found worldwide. They feature a genital plate in the female, serrated bristles on the tarsus of the 4th leg, and a sticky capture silk type of web. They can live in larger webs woven by other larger spiders; they may consume the larger spider who made that web. Those little guys are not such skilled webcrafters and usually make messy webs in sheds or on bushes. Some spiders create a web each morning, destroying it each evening. The diet of the cobweb spider consists of insects and crickets. They have weak jaws and use their fangs to inject their prey with a fluid. This fluid helps break down the tissues of the insect so the spider can more easily ingest.

Jumping spiders trail a dragline instead of spinning a web. This single filament can serve to follow the air current to attach to some permanent fixture, securing egg sacks or simply providing escape route if the spider feels threatened. Female spiders can produce egg sacs that contain hundreds of eggs, but most are eaten as the mother abandons them at birth.

Finally, there are only two spiders in this country that pose a danger, and every other spider is virtually harmless. The brown recluse is really very shy but could get aggressive if threatened. While usually brown, the recluse can be more of a dark yellow. A dark line across the upper side of the thorax may resemble a violin. For that reason, the brown recluse is sometimes called the fiddle-back spider. A bite is recognizable by tiny fang marks in the skin. Tissue deterioration is the result of a brown recluse bite.

Common hiding places of the brown recluse in the home may include closets, sheds, or cardboard boxes. Also, a brown recluse could be hiding in a brush pile and or stacked pile. If an isolated spot is disturbed, the brown recluse could become aggressive. The brown recluse is found only in the United States, primarily in the South and Southwest.

The other dangerous spider is the black widow. The black widow bite shows fang marks and an area of swelling surrounding the bite. The black widow generally favors the same hiding spot as that of a brown recluse. They live in warm temperate climates, drain pipes and other dark places. The black widow has two black body parts and strong jaws with poisonous fangs. With a hard protective exoskeleton, females are 1/2 inch long with a red hourglass on the bottom of the abdomen; males are smaller (ĺ inches) with longer legs, having black and yellow markings.

The best way to avoid the bite of either the brown recluse or the female black widow is to be sure that windows are sealed to block entry into the house. Prevention is the best way to protect oneself from the very small, but potentially lethal, threat of a poisonous spider.

Arachnophobia, the fear of spiders, is said to be the most common creature-based phobia in the world, yet the majority of spiders are harmless. They are predators of invertebrate animals -- and humans, of course, do not fall into that category. A spider bite to humans is a response to threat. Just staying clear of the spider is the best alternative.

Wolf spiders hunt insects in the garden. I never disturb a spider in the garden so it can continue to do its job. I seldom spray in the garden to preserve the natural eradication process already in progress there. Similarly, the cellar spider is beneficial because it hunts black widows, and the brown recluse hunts and consumes cockroaches found there.

On a final note, spider venom can actually be used to the health benefit of humans. Aside from the eradication of unwanted insects, spider venom has been researched for years by neurological experts to prevent brain damage in stroke victims. Maybe next time you should think twice about stomping on that spider!

Read other articles about controlling insects & garden pests

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