You need to look around for the eggs.They are round with spikes all over them, usually in clusters in the web. Unless you get rid of the eggs you'll always have problems.

 

My bug guy tells me the same as was posted earlier. Unless the the spiders body comes in contact with pesticide it has no effect. Here in north Ga I have a lot of blck widows and brown recluse. I have found that if you a near new construction the widow population will be like mice, the more clearing going on around you they will be everywhere for a year or two then taper off.

The most effective thing I have for decreasing their population is an old shoe. Just like carpenter bees, kill enough of them and they will go elsewhere.

NUMBER ONE protection against getting bit................ Where gloves when you are putting your hands where you cannot see. Spiders tend to stay away from high traffic areas.

 

I would have to agree with the post regarding the product with Dursban. Dursban will last longer and is a much stronger product than most of the others. Products with Pyrethrins and Permetherins (a synthetic pyrethrin) do not last nearly as long, and they are far less toxic.

 

Either shoot at every one you see with a 12 ga. If that doesn't work, try using Napalm.

 

Use a bug bomb with any pyrethroid as the active ingredient about 10 days apart. that will take care of it assuming they aren't re-entering your garage from somewhere else. I wouldn't use anything with chlorpyrifos in it, i.e. Dursban or Lorsban in the house or garage.

 

The Bug bomb WILL come in contact with them.

 

Black widows are only found down close to the ground, so spraying in your garage around the floor area and up about 1' with a organophosphate based spray will give you a longer lasting pesticide that is more effective on spiders than a standard "bug-bomb" from the hardware store. Unlike using a bomb, when you spray you dont end up with the pesticide covering the surface of everything in the garage. Yeah, the Dursban is more posionous, but generally around the floor in the garage is a fairly safe place to spray with these products.

If your willing to spend a little more on the products, the best bet is to purchase a microencapsulated or wettable powder product containing a cypermethrin to apply with a sprayer. These products will last for possibly up to 90 days and still be somewhat safer than the Dursban.

 

Wrong! about them remaining close to the ground as I've commonly seen them in out door power and phone pedestals from Alabama to California. The misuse of organophosephates by home owners has been one of the many arguments for and aren't that great against arachnids. The bug bomb with a Pyrethroid active was suggested because the truck is infested and would put fumes where they need to be and get the spider via book lungs. Cypermethrin is a pyrethroid. I wouldn't spray my truck with a wettable powder or any other thing.

 

I have to disagree with you on the location that black widows are commonly found. Sorry, It is a well known fact that black widow spiders are not commonly found far above ground level but I'm sure there are a few exceptions, after all were dealing with spiders, right?

As you have stated, the use of organophosphates is arguable, and many favor their effects, including professional usage on a regular basis at the residential level.

The use of cypermethrin is suggested as wettable powders and microencapsulated are the only types of pesticides in the permetherin family that have any reasonable residual effect for spider control.

My understanding was that after the truck was parked in the garage the concern was widows found later in the garage, hench the spray suggestion vs a harware store bug bomb.

 

Can you even get Dursban anymore?

 

I'm surprised that it is available, espicially here in California. But yes, it is still available on the consumer shelf.

 

You can disagree about the Lactrodectus mactans can be found a couple of feet of the ground in cavities in rock walls, phone and power pedestals and old cars, I've seen hundreds like that. Granted, I've seen thousands under rocks, logs and boards. In fact, that is typicall of many of the comb-footed spiders, including the Brown Widow recently introduced into LA. I suggested a pyrthroid based bomb because of fumes and taking the spiders out on contact with their book lungs. The whole idea behind some insecticides and acaracides is NOT to have a residual. I personally wouldn't want to roll around in an OP or any other insecticide on my garage floor. Ever here of Parkinson's disease? I personally know 4 retired PH.D. entomologists that retired early due to Parkinson's and all worked around OP's over 25 or more years.

Lorsban (same contents a Dursaban, chlorpyrifos) is still registered for agricutural use in California including citrus and I agree its a good tool when used properly.

Edit: Actually, I wouldn't necesarily say Lorsban/Dursban is more poisinous because that gives the wrong impression. It depends on the target organism.
The pesticide label is the legal document on usage and require personal protection equipment. It will also have information such as Warning, Danger or Caution in regards to how hazardous it may be to humans. In the case of Ag materials materials, it will have REI (reentry interval) and PHI (preharvest interval).

Edit: Edit: The exception is that I would use chlorpyrifos around the corners of doors and garage doors for preventing various infestations. But one of the biggest down falls has been it being used on kitchen and living room floors and babies and toddlers crawling through it.

Edit: Edit: Edit: In areas with heavy Brown Recluse populations, a contact residual on the garage floor behind tool boxes etc. would be very effective.

 

Humm, it seems that you agree on many issues ..edit..edit

I suggested the use of a OP's for specific target areas where spider might live to continue to provide control, not for use out in the middle of your garage floor where you could roll in it. Heck, I wouldent be wild about rolling around in and picking up everything with the carrying agents left behind that are used in those coveted bug bombs if your concerned about chemical contamination,lol!

I dont believe anyone suggested spraying in a matter inconsistant with the labeling? Using many products improperly can lead to serious consequences. You'll probably find someone that swears by a old bottle of Chlordane for their interior use, despite the long term effects.
Unfortuantly there are many people who work or have worked around pesticides for many years that dont follow all the protection equipment guidelines, all that gear can be pretty stifiling and you sure dont feel the long term effects right away.....

On the other hand, many WP products are qualified for use on most surfaces within homes with the REI being as short as the time that it takes the product to dry.

 

The sticky trays work.

 

The only thing I like about the bug bombs is that they are a simple way to fumigate a confined area for quick knock down of pests that are hiding in cracks and holes.