Bark beetles primarily infest?

Bark beetles are primarily associated with infesting green logs and firewood. These insects are attracted to trees that are still alive but have often already been weakened or stressed by environmental factors, making such trees more susceptible to infestation. They tend to lay their eggs in the bark of these trees, where the larvae hatch and feed on the inner layers.

While they can impact both weak and healthy trees, their most significant presence is in areas where the wood is still fresh and has a higher moisture content, such as recently cut logs and firewood. This contrast with the other options emphasizes that bark beetles prefer materials that provide the best condition for larval development, which makes green logs and fresh firewood ideal environments for their lifecycle.