Are the ants in the picture carpenter ants?
Your experts responded recently the ants in the pictures that I sent you are not termites. Although I was relieved, I am still worried as after sprayed a few times I still saw the dust and more dead or half alive ants (they eventually died) near the wall on basement floor. These ants seemed bigger than what I remembered the size of ants. I didn’t use bait inside as I worry about bringing in more ants. I am planning to try boric acid as bait outside later. Please answer my question and advise me on treatment. Thanks!
One more question, I am going away from home for about a month about 2 weeks from now. I am worried about possibility that ants will be everywhere in my basement since no one will spray ants during the time I will be away. There is no food in my basement, and no other part of my home ants were found invadingants there.
We cannot make an accurate identification from your photo. You can resubmit clear photos so we can see what you may be dealing with. This looks like it may be carpenter ants but other types of ants will nest in compromised areas like foam insulation or wet wood.
If you sprayed the nest, it is possible that you may have controlled them but we cannot say for sure. You will have to do more detective work. See if you can find out where they are coming in. Look for damaged, wet wood, leaks, etc. Go outside and look in the area. Carpenter ants are most active after dark. Look in the basement at night and outside and look for ant trails. Sometimes ants use foliage or branches contacting the house as skywalks to increase access to the house.
If you find compromised wood or leaks you will have to repair this. Apply a pesticide to the nest if need be. You can also put outdoor ant bait stations outdoors if the nest cannot be located.
Here is more information on carpenter ants/ants for nest location in or outside the home, prevention, and control. http://extension.umd.edu/hgic/carpenter-ants