The bark beetle is a small insect that primarily lives under the bark of trees. These beetles are known for their role in forest ecosystems, where they help decompose dead or dying trees. They are typically brown or black and can vary in size, with some species measuring just a few millimeters long. Bark beetles are often associated with tree damage, as they bore into the bark to lay their eggs. The larvae feed on the inner bark, which can disrupt the tree's ability to transport nutrients and water. This can lead to tree stress or death, especially during outbreaks when beetle populations surge.