For Log Homes, the large carpenter bees or Xylocopa do the most damage, boring approximately 1/2" diameter tunnels into logs and other wood surfaces including decks, overhangs, fence rails, etc. Carpenter Bee tunnels become a threat for infestation of wood-decaying fungi or other insects, such as carpenter ants.
Treatments: Insecticidal sprays and dusts such as those included in the Carpenter Bee Kit are available. These types of products may need to be applied every couple of weeks for awhile to ensure effectiveness. Apply them at night while the hive is asleep for maximum impact. Beware that some insecticides have been banned but not yet removed from store shelves. Consider the potential health risks of using such poisons in your home (young children are the most susceptible). If you have an exterminator do the job professionally, find out what they are using and if those insecticides have been banned in your area. If you are having or have had problems with Carpenter bees, consider adding NBS 30 to your finish when you recoat your house again. If chemicals aren't your bag, you can give the kids a project with a couple of fly swatters. The males don't sting and the females are known to be more reluctant to stinging, unlike other bees, wasps, and hornets
However you choose to rid your logs of carpenter bees, consider spraying Tim-bor or Shell Guard RTU in the tunnels afterwards to help guard against wood-decaying fungi. Just mix up some Tim-bor in a spray bottle, pump sprayer, or squeeze bottle and administer it into the holes. Also, be sure to seal off the tunnel entrances by pounding in wooden dowels or by using Caulking, wood putty, or by mixing WoodEpox and sawdust.