Is landlord responsible for spiders?

[Jane S.]

The large family in one of my rentals is freaking out about black widow spiders, but I had never seen a spider, a web, or any infestation in the house before they moved in. I advised them to spray all around the foundation and wherever there might be a way for spiders to get in. However spiders love flies, and tenants dog poop is sitting out in the yard, uncollected, so maybe that has something to do with spiders coming around. The lease requires tenants to keep property in clean condition ... yet they expect me to pay for exterminator ... I have paid for a number of updates but it seems to me the dog poop needs to be better disposed of. And they are responsible to deal with bugs etc. What do you think? I have spiders at my house, they seem pretty harmless.