A couple days ago I noticed ants entering one of the vent openings under the house, and exiting another one. I went nuclear and sprayed all the vents with malathion. This morning I noticed a few ants in the bathroom (they got up close and personal with Mr. Thumb), so I checked around outside and saw a few ants going in and out of one of the vents. So I blasted all the vents again with malathion.
This evening a found a dozen or so ants in the kitchen. I sprayed the cracks and a few surfaces with pyrethrum. Compared to other poisons, pyrethrum, which is made from chrysanthemum flowers, is relatively safe for humans and breaks down fairly quickly with exposure to sunlight and air. I did some cleaning in the kitchen, took out the trash, even started the oven's cleaning cycle, hopefully that will eliminate anything of interest to the ants. There's much tastier stuff outside... where I can blast them with poison....
I'm hoping these ants are just survivors of the ones trapped under the house when I poisoned their exit. Hopefully they haven't managed to set up a colony underneath the house.
The ants originally came from one of the neighbors, probably the very poorly kept lawn of the elderly lady next door. I've been battling these ants for years, I hose down their trails all the way to the property line, but they eventually come back when the poison breaks down. I'm going to be annoyed as hell if they set up shop here and I have to pay for an exterminator.