What type of beetles feed exclusively through active tunneling under the bark?

Bark beetles are known for their behavior of feeding exclusively through active tunneling under the bark of trees. These small insects use their mouthparts to create tunnels just beneath the bark, where they feed on the cambial layer and the inner bark, which is rich in nutrients. This feeding habit is specifically adapted to their life cycle and diet, allowing them to access the necessary resources for survival and reproduction.

Bark beetles particularly have a significant impact on forest health and ecology because their tunneling can disrupt the flow of nutrients within the tree, potentially leading to tree decline or death. The tunnels they create also serve as a habitat for certain types of fungi, which they cultivate and eat, creating a mutualistic relationship that further influences forest ecosystems.

In contrast, ambrosia beetles also tunnel into wood but feed on fungal cultivars rather than the wood itself, while powderpost beetles target hardwood and feed internally, though their method does not involve tunneling under the bark as specifically as bark beetles do. Termites typically consume wood and cellulose within structures but are not primarily associated with active tunneling under the bark of trees.