Why do I see more spider webs in the fall?

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Question Why do I see more spider webs in the fall?

Answer It takes most of the summer for some spiders to grow up. When the spiders mature, they make little spiders (lay eggs). In order to have the energy to produce their eggs, they have to eat. They eat by catching insects in their webs.

The most common spiders in the fall are called orb weavers. There are several families of spiders in this category. These spiders create orb (circular) shaped webs. The largest and most colorful orb weaver is the Golden Garden Spider or Writing Spider (Argiope aurantia). The most famous writing spider was named Charlotte. Charlotte's Web is a story about a writing spider on a farm.

Every night garden spiders either spin a new web or repair their old web. Insects that travel at night get caught in the webs. These spiders have relatively poor vision, but are quite sensitive to vibrations. The mama spider often hides off to the side with a thin silk thread attached to her web. When an insect lands in the web, her thread quivers and triggers her into attack, kill and eat mode.

Male writing spiders are smaller than the females. Male spiders build a small web either nearby or in an outlying part of the female's web. Potential males court by plucking and vibrating a female’s web. Male spiders like living on the edge in more ways than one.

To make webs, spiders produce silk from glands called spinnerets. Orb weavers can have three or four pairs of these glands, each producing different textures of silk (non-stick silk for the radial web lines, and sticky silk for the spiraling strands). Spider silk is a protein that hardens as it is stretched from the spinnerets. It may appear fragile, but it is unbelievably tough. The relative tension necessary to break it is far greater than for steel.

Orb weavers are reluctant to bite people. If they bite, symptoms are usually negligible. You may experience mild local pain, numbness and swelling. Obviously, you need to go to a doctor if you feel ill. The old saying about a person dying if a writing spider spells your name in her web is not true. They can't really write.

Poisonous spiders, like the black widow and brown recluse, do not make orb shaped webs. They make cobwebs (irregularly shaped webs). Cobweb spiders are usually found in the house, in a barn, under equipment, in the wood pile, etc... Clean the cobwebs out, but leave the orb webs.

Spiders found in the house are usually not the same species as the garden spiders. Most indoor spiders belong to a small number of species specially adapted for indoor conditions (constant climate, poor food supply, very poor water supply). Some house spider species have been living indoors since the days of the Roman Empire, and are seldom found outside.

For more info visit http://aggie-horticulture.tamu.edu/galveston/beneficials/beneficial-24_spider_blackandyellow_argiope.htm If you don’t have internet access, then call me at 910-893-7530 or email gpierce@harnett.org You have to question the male spider logic. “I’m going to get my wife in the mood by putting her in the attack, kill and eat mode. We’ll either make babies or she’ll kill me.”

Gary L. Pierce

Horticulture Extension Agent

Harnett County