What it does: Not much. Yeah, it’s dead. It’s all messed up. Mostly you use them to open doors.
How to make it:
You don’t have to kill any trees. Nature has done that for you.
What it makes:
Most obviously, you can chop down this tree with an Ax to get Wood.
You can also get yourself a Stone Seed if you combine the Dead Tree, a Heavy Rock, and an Ancient Mortar.