Beavers use trees to build dams. Dams can be up to 40 feet long and 10 feet high. They also make scent mounds that mark their territory.
Tree Frogs have big toe pads so they can stick to trees.
Monkeys use trees for travel. They swing from tree to tree.
Squirrels use trees to escape from preditors and to store their food.
Salamanders use decaying trees to hide under, to keep them cool and out of the sun.