Air layering is an "on plant" cloneing technique that involves stripping about 1/2 inch of the outer stalk adding hormone and wrapping the area in a small piece of plastic baggie creating a ballon like around that area. the roots start growing in side the bag then ya take it off. its like surgery you really got to be VERY carefull to just cue the outside layer of stalk in an area where you would normally cut for a clone.
I was high when I posted this. Ended up googling it anyways. But just so you know, When I'm high. Google is out of the god damn question. Don't go there. lol.