Their nest is much more of a concern. These nests, if left untreated, will result in extensive structural damage and will result in costly repairs within a few years. The female will go in and out of the nest so patience will show where the entrance is. Killing individual bees with a liquid insecticide will not destroy the bee's young. Carpenter Bee Control Biology.
Carpenter bees get their name from their ability to drill through wood and nest in it.
This hole is usually located on the underside of any wood surface including siding, soffits, overhangs, decks, fence posts, fascia boards and window frames. Although the hole appears to be only an inch or two deep, it doesn't end there. The female will turn 90 degrees and bore a channel from 6 inches to as long as 4 feet. This channel serves as a main corridor from which she will drill small chambers a few inches deep. These chambers become egg holders.