I needed to render the trees as a test too, so I covered up most of the ground.............
It's a fractal terrain not heightfield so it's a little harder to know a certain size unless I use a SSS. Like I said............testing. If I can get the 4k sample to work halfway decent, I may see about some 8k textures.
Kadri............it may seem expensive at first, but Speedtree is probably one of the best software purchases that I have ever made. With a few clicks you can have a forest full of trees..............and their "low res" versions can just about be "Hero" trees. And they are very lightweight as far as polys. Not so with HD trees, they tend to be somewhat "fat".
