Seems logical. Will try in the future. Was planning on using a painted shader to control the tree lines, but got sidetracked and ended up not bothering.
**EDIT**
Oh, ALTITUDE! I was thinking of attitude (as in angle) and was somewhat confused...
Well, while I'm here there were two other versions along the way, I would have preferred to keep the water from V1 but I somehow messed it up and couldn't get it right again and after a seemingly endless set of crop renders I gave up. Weird color issues cropped up in V2 that I had to revert all my surface layers to get rid of. I'd gotten to a point where I felt no clear end was in sight and was adding stuff for stuff's sake...
...and I've been down that road...