Slang for marijuana. Combination of trees and reefer.

the whale tail is the shape formed when a g-string rides up high over a womans trousers

A treefer is a person who shows significant similarities to the external appearence of a tree. This word is also used to describe a person who similarly shows the main characteristics of said tree.
The person therefore is a dull bastard.
To be treeved by a treefer is to be bored shitless.

bro weed