Seeing the forest....and the trees

I have been trying to figure out what to do about the transition between backdrop and scenery. I was able to get the ground cover the way I liked it and then with some painting I move the forest up to the edge of the scenery. The next step was to start building trees...and trees and more trees. I still am working on my technique but I think I am getting there. I think my next step will to do some more tree trimming and adding the remainder of the trees.