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A hippie squatter, who, under the guise of protesting the harvest of old-growth redwood trees, makes a home (sometimes for years) in the branches of a tree marked for harvest. Known for: basking in the media limelight, a narcissisticly romantic self-image as an eco-warrior (and possible author, if they can land a book deal!), and creating an opportunity for all their treesitter-wannabe buddies to erect a small tent city around the target tree. Also known for displacing hoards of native animals and insects from their woodsy homes, and wreaking havoc on the environment and the tree itself, by dumping massive amounts of trash and human waste, attracting untold amounts of foot traffic, and the non-stop pumping of diesel generator smog, fumes, and noise, into an otherwise pristine and untouched redwood forrest.
Dude 1:

"Hey man, you remember that homeless dirtbag hippie dude that used to hang on the corner and panhandle? Did he croak or something? I haven't seen him around..."

Dude 2:

"Last I heard, he hitched a ride to Humboldt and became a treesitter."

Dude 1:

"Bet he's lookin' for a pot o' gold at the end of that eco-rainbow!"
by mr_dujour January 29, 2012
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