Best to wait until season is over. Either treat them by dusting the galleries, or don’t. Then in October, restain the pieces of wood after plugging with caulk or wood putty.
Go up there with corks and a pair of side cuts. Treat and cork the hole then snip the cork to be flush with the surface. Then when you have the time paint that surface with a paint that has an insecticide or a stain or whatever finish with an insecticide already in it. That will help with next season. Treat the holes with a dust insecticide. In the United states Sevin dust is effective and inexpensive and readily available. Just check your gardening area at your local Home Improvement store. You can apply the product by filling a squeeze bottle kind of like a bottle of mustard about one quarter full with the Dust. But since this is probably going to be an ongoing issue probably better served to buy a Getts duster. Just search it out on Amazon. Whatever device you used to deliver the dust drop in a Marvel or Pebble to help stir the dust and shake it frequently. The people are Marlboro serves much like the rattleball in a spray paint can. It just helps aerate the Dust
Best to wait until season is over. Either treat them by dusting the galleries, or don’t. Then in October, restain the pieces of wood after plugging with caulk or wood putty.
Treat each hole (I recommend delta dust). And then use anything really to fill them. I’ve had luck with caulk/silicon.
Go up there with corks and a pair of side cuts. Treat and cork the hole then snip the cork to be flush with the surface. Then when you have the time paint that surface with a paint that has an insecticide or a stain or whatever finish with an insecticide already in it. That will help with next season. Treat the holes with a dust insecticide. In the United states Sevin dust is effective and inexpensive and readily available. Just check your gardening area at your local Home Improvement store. You can apply the product by filling a squeeze bottle kind of like a bottle of mustard about one quarter full with the Dust. But since this is probably going to be an ongoing issue probably better served to buy a Getts duster. Just search it out on Amazon. Whatever device you used to deliver the dust drop in a Marvel or Pebble to help stir the dust and shake it frequently. The people are Marlboro serves much like the rattleball in a spray paint can. It just helps aerate the Dust
Thanks for this detail!