Trees go through there lives in a state of just being, soaking up the sun and just living. Treeism is the consept of going through life, being yourself, having limited negativity on others and enjoying life.
Ex.1 Those treeist hippies set up their tents in the woods behind my house, somebody call the 5 oh!!!
Ex.2 He is such a treeist, are those pants made of leaves?!?!
Ex.3 She practices treeism by laying naked in public parks.