jigslinger

I found that with recluses, the bug bombs work pretty well. I'mpretty sure they would kill black widowsbut I know they work on recluses. Put two or three in your garage and close all the doors til the next day. The problem with the sprays is you almost have to hit them directly with it to kill them. With the bombs, the fumes seek them out where ever they're hiding. When I plan on cleaning my garage, I do this a few days before and you'd be surprised how many dead ones I find. They're relatively cheap so it's worth a try.

Midnight Rider

Beware of pilot lights before setting off insect bombs in inclosed areas or you may get more of a bomb than you bargend for. Spiders not like insects do not groom themselves. There fore it is harder for them to ingest a lethal dose of pesticide. This is why you almost have to spray insecticide directly on them to have any effect. Good house keeping is a good method to deture spiders from taking up residence in your house. Aslo there is a good product made called Cob Web Elimanator. It is not a pestcide but when applied to surfaces such as garage walls it keeps spider webs from adhering to the walls thus making it impossible to construct a web. Black widows do not build a traditional looking web. Theres has a funnel apperance and is constructed usually inside a cavity of some sort. During the day the female spider is at rest in the back of the nest but at night moves to the entrance. Usually there nest are easy to spot due to trash and debre that cling to the nest such as grass clippings. They almost always nest in a dark dry areas out of sunlight and almost always never above 2-3 ft off of the ground.The female will spend her intire life at her nest. It is rare to see one out in the open like the one pictured above. This spider must have been disturbed.We also have a very good population of Brown Widow spiders in the Beulah area. They both have the distinctive red hour glass except the other is brown. First symptom of Black Widow bite is severe abdominal pain.

jigslinger

By all means make sure there are no sources if ignition of any kind. I even unplugged my freezer for about 8 hours.

InTooDeep

Thanks for the advice guys. Its basically a brand new detached garage without too much clutter and no sources of ignition, so I'll give the bombs a try.