Adult males can weigh as much as 600 pounds. The southern flying squirrel, a secondary cavity user, is selective in its choice of cavities. While they will use a variety of cavities that are 20 to 30 feet above the ground, they prefer those constructed by downy woodpeckers. They usually line the cavity with shredded bark, but also will use lichens, moss, feathers or leaves. Insects Cavity users aren't limited to birds and mammals, or even vertebrates.
Honeybees use cavities, and so do carpenter ants.
They build their nests in the heartwood of dead trees, logs and stumps by chewing through the interior of the tree and creating an intricate network of tunnels. Each colony contains about 2,500 workers, some males and a queen. The Conservation Department recommends leaving or establishing a minimum of seven hollow trees per forest acre. These trees should be marked and saved when harvesting timber. If no suitable trees exist, girdle or wound selected individuals to create snags or hollows in future years.