Bark Beetles

All bark beetles are relatively small in size with the largest species in North America being approximately 5/8" as an adult. Many are from 1-6mm. For the most part, bark beetles require a previously stressed host plant in order to be successful at colonization. Adults will tunnel under the bark in the nutrient-rich area, create species-specific galleries, and deposit eggs. The larvae tunnel within the inner bark / outer wood interface, whereupon they will pupate and emerge as adults. Their feeding usually compromises the vascular system of the plant to the point where it dies. Once bark beetles colonize a tree, there may be little that can be done to save the plant.

Certain bark beetles, known as ambrosia beetles, are able to go deep into the nutrient-poor wood by carrying a fungus with them that grows on the walls of the tunnels and feeds the larvae. The Black Stem Borer is an example of an ambrosia beetle.

Bark beetles index:
Conifer Bark Beetle
Elm Bark Beetle

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