The "cellar spider," family Pholcidae, is our most common local cobweb builder and the one referred to in this article. They grow up to an inch or so across. Black widows and their relatives are more commonly considered cobweb spiders, going by the Internet.
Cobweb spiders have hatched, and are dirtying houses with their dirty little webs. Unlike other web builders, a cobweb spider doesn’t clean and repair its web; it camps until the web gets dirty and then moves on to another spot, the homeless vagrant of the web-spider world. A dirty, visible web is useless to the spider, except to steer flies into its new, invisible web. But they sure mess up a house, inside and out, and shrubbery as well. Cobwebs scream neglect to thieves and encourage other disorderly conduct, like littering and breaking windows.
Last summer’s fires were very hard on cobweb spiders and other web builders, showing up their webs with ash. Cobwebbers starved except under cover; they could not build new webs fast enough, though they sure tried, covering shrubs all over town. There have been relatively few cobwebs this spring until now.
Daddy Long Legs, AKA harvestmen, family Opiliones, are not spiders, having one body section, not two.
Daddy long-legs have become common where they were rare, as they don’t build webs, but just walk around. Cobwebs certainly mess up their hunting range, and could be a hazard to them.
Rain is also hard on cobweb spiders, because they are delicate, and too much water can stick their legs together. Rain also shows their webs, so they build webs under cover until the weather is dry, when they spread into the shrubbery. This is another good reason to use sprinklers rather than drip or soaker hoses, besides making rain.
A customer’s neighbor in her duplex has rough siding covered with tiny, dirty spider webs, with larger webs under the eve on his front porch, but she had few on her portion of the duplex, and she has needed little web cleaning thus far this year.
This standing mister usually sells around $10.
Last year, during the fires, she started using misters to keep her plants happy, settle the smoke and breathe easier, and she has loved the results. When they are on, it takes only a few minutes for them to show all the webs within 8 feet, allowing this gardener to clean them off with a web duster.
There are many brands of this tool available on the web.
A web duster, a pom-pom shaped broom head that can be attached to an extendable pole, is also needed for cobweb spider control, since as soon as the misters are turned off and the webs dry out, they are good for catching food again, and the mist doesn’t reach to the high eves. Using a duster alone, it is an endless battle to keep the cobwebs down. The two together can do wonders.
If you don’t have misters, cobwebs in shrubs are better controlled with hoses and spray nozzles that adjust from spray to jet than with a web duster. Or you can use a sprinkler and web duster. But the jet reaches inside the shrubs where you can’t see.