Powder post beetles

5810  Hi could you identify what insect makes these holes? I believe it may be a beetle of some kind. Brad.  Walkerton Ontario.

The size of the holes and the very fine sawdust would indicate powder post beetles are doing the damage.
See http://tinyurl.com/gqgf7gr for tips on distinguishing the types of wood-boring beetles based on their frass characteristics. Ed Saugstad, retired entomologist; Sinks Grove, WV.