The Tree Stump is a type of naturally occurring resource. They can be picked by pressing 'E' (or whatever your action key is). Upon being picked up they will yield 50 Wood.
Tree Stumps spawn randomly across the landscape and can be a convenient source of Wood for fresh spawns. However, later on as the player gains access to better tools such as the Hatchet or Chainsaw, Tree Stumps can be ignored.
Note: Tree Stumps do not spawn after felling a Tree.