Its definitely not from solutions that are sprayed onto the leave. I my last grow I did not spray anything, and still got foam when making bubble hash.
I would agree with Cannalingus, makes perfect sense.Would it be stupid to assume tat cannabis plants exude fats and oils that are similar to soaps, or that this is the emulsion of non water solubles like terpenoids (oils) that in turn causes this when agitated?