Ambrosia Beetles: Identifying Characteristics
Identifying the injury:
Ambrosia beetle attack can be recognized by piles of fine, whitish dust found around the 1/16" entrance holes or at the base of the tree. In lumber, the fungus darkly stains the galleries and these stains can easily be seen.
Identifying the insect:
Adult beetles are long and thin, usually about 1/4" long. They are reddish brown in color with sharp spines at the back end of their bodies. Fully-grown larvae and pupae are the same size as the adult beetles but are yellowish white in color.
Susceptible trees:
Ambrosia beetles attack most tree species. The beetles target very weakened, dying trees, green logs, and unseasoned lumber. The beetles will only attack trees and logs with high moisture content.