There is a book totally devoted to growing in trees.

Invisible Marijuana and Psychedelic Mushroom Gardens by Robert
Bunch.

Check Amazon as it is out of print.
ericwt Reviewed by ericwt on . grow in a tree i havent tried this but had a freind a while back that grew a plant for a while about 7 feet up in a tree,, the top of the tree was fucked up and it was hollow so he filled it with dirt and planted a seed, it died after about 2 weeks Rating: 5