Thank you for your question. No, our product will not kill harvester ants.
Thank you for your question. You will know the bait stations are empty if you no longer see ant activity around the stations or your ant activity increases. You may also turn the bait upside down and look through the access hole; you will then be able to see the "bait cake" inside.
Yes my little cat had slaped it away one after another down stairs. She did not get along with the ants.
Probably not, besides you need to treat each mound or colony (like under a rock or landscape timber). There are thousands in the colony so this would be cost-prohibitive. Use a granular insecticide to treat the entire lawn, if you desire. There are dusts to sprinkle on the mound that work very well. There are fire ant baits to sprinkle on the mound that work but not as fast.
You need to place them near where the ant trails are. Put them right over the trail. You could place scotch tape around the edges to help the ants continue their travel into the opening; however, I've not had to do that and the species that I am controlling walk right in. I stapled the traps to the vertical outside trim where they were trailing. (they seek out dry rot) Otherwise, move the traps to different spots, but where the ants are seen. Probably you have other species; unfortunately the mfg. does not state the species that are controlled. They should do that. The liquid baits work good on so-called "sugar ants."
I really like the hotshot Ant baits. They always work very well for me. I get ants every spring and summer and find them in one of my bathrooms, in my kitchen, near my dogs food bowl and near my sliding doors going to the yard. I recommend using them with a bait station cover. They make the baits descrete and keep them away from the kids and pets. I use the TrapJak bait station covers. They work great and stick on the wall and blend in nicely so you don't notice them at all.
I am sorry I can not answer that - the specs. online with the product will list the type of crawling ants they are developed to kill. It is a bait system which means the ant crawls in the holes on the sides and takes the bait back to their nest to the Queen ant and this kills the Queen ant which is needed to hatch more ants for the colony.
I use them for red and black ants. When I get carpenter ants however, I get an exterminator as they can destroy property by eating foundational wood, like termites do. The product will describe the ants they kill - I live in Pittsburgh, PA and get more red ants than anything else and I use this bait product for preventative only. For an infestation, I would get a spray and read the instructions about where it is safe to spray it, which is only in placed where people and pets are not touching, as all insecticides are toxic to humans. Put these bait traps inside back door closets where your garden and grass is closer to the house, and under the kitchen sink and change them every 3 months, being careful to discard the used traps properly per instructions.
I got them using the traps immediately (little black ants) and the ants were gone in a couple of hours and haven't returned (now in 3rd day). That's in a workshop, where they were getting into dry rot on the building's trip. If you use sprays, the traps will be ineffective because the ants need to be actively feeding and trailing back to the nest (to kill the queen). Sprays don't reach the ants in the nest or in the walls/cabinet bases, etc.
I would think they would be OK but check with your plumber as they are qualified to answer this question. The baits are plastic and heat may affect the effectiveness to the bait inside. I use them only under my sink inside the cabinet door and my back door closet nearest the back door where ants can enter from the grass nearby.