In any area which has black widows, desert recluses, brown recluses, or anything in that nasty group, you need to:

1. Shake out your shoes before putting them on. One of the most common ways people get bitten is that these spiders like small dark places. Like the toe of your shoes. They crawl into there and go to sleep, get rudely awakened, and bite.

2. Avoid putting clothing on the floor, and if you do, shake it out before putting it on. Same reason.

These spiders don't want to or enjoy biting people, they are reacting in self defense because you just nearly accidentally squished them.

And wherever you go, if you are hiking, don't sit or put your hand on a rock, stone, or stone wall without inspecting it for critters first. That's how people get stung by scorpions. Arizona has the Arizona bark scorpion, which is extremely venomous and occasionally kills people. Again, they aren't attacking you because they want to, they just feel threatened. Venomous spiders and occasionally snakes also hang out on flat surfaces. They like the warmth.