A general spray for spiders is not recommended, unless the infestation seems severe. Tolerate what you can, spray with an aerosol what you can't. The only dangerous spiders we have in Iowa or Illinois are the brown recluse spider and the black widow spider. The brown recluse is not common. The black widow is common, but reports of it biting people are infrequent.
Most spiders can live for several months without food.
Therefore, controlling the insects upon which they feed is a very slow control technique. Sanitation is the most practical method of spider control. Clean away all webbing with a vacuum cleaner so that eggs and spiders are picked up and destroyed. Ordinary housecleaning with a cloth, dust mop, or broom is not effective. Keep premises free of unneeded, undis-turbed clothing, papers, and other litter.