I use the terrain editor for modeling, - but when I build house structures (re. you photo reference) I use latices... :) It's usable on both sides.

Also, to make a thick forest, I don't use a lot of trees. I use either cylinders or trunk freebies. Then I use bryce trees (if any) as brances. Unless you render the wood from a brid's eye, your visual isn't whole trees. When you walk there, you will see undercover, and brances. So I stick bryce trees into the trunks to show an occational branch. Other than that it's smart to use undercover, made up by 2d faces with leaf textures (with alpha channel) this takes a lot off the render time.

Britt