Basically, someone who works on their car by themselves, as a "do-it-yourself" project. He/She often employs jerry-rig techniques to fix his/her automobile. Could also apply to anyone who is a "do-it-yourselfer" in any aspect of life.

When you eat dirt for the first time and leave your family to build a shack in the woods

Used in the movie "The Mack"

Literally the Shade Tree that everyone sits under to rest. A guy that stupidly supports and provides wealth for a whore, her family and her bastard children.

A motion you do when someone is SO unbelievably shady, that all you can do is put your arms over your head, like you're a shade tree. You must declare "Shade Tree" while shade tree-ing, so that the person understands how extremely shady they are.