blueman wrote:
We seem (like many in our neighborhood) to have a nagging number of
Carpenter ants around our New England house.

We bought Home Depot's "best" which supposedly "kills on contact",
however, the ants seemed to just swim through the stuff.

What are your recommendations for the most effective *consumer* spray
that effectively can be used against Carpenter ants? (both inside and
outside).

My perhaps faulty assumption is that anything sold nowadays to
consumers will be reasonably safe.

Around or in? If there is damp or dead wood "around", there will be
caprenter ants. A hollow tree, dying limbs, dead wood in hedges,
damaged wood fence or siding. We had loads of carpenter ants around our
condo, with folks dumping bags of poison all over,to no avail. What got
rid of them was getting rid of dead wood in landscape and repairing
damaged wood on structure. They forage in the evening, so are pretty
easy to track to their nest. Put bait where it won't get washed away by
rain if they persist after repair and caulking. One favorite means of
entry is from trees in contact with roof; others - gaps in siding or
around plumbing entry. Only rarely were they seen indoors - one kitchen
of the condo, attic with leaky roof.