Okay here are two new population renders. The first one took 105 hours to render with four populations, render quality 0.9, AA 9 and (sadly, I forgot to change it) 16 atmosphere quality along with soft shadows. All things considered, I'm a bit disappointed with it. The image suffered I think from the atmosphere samples and the trees just look like clones in some areas. I'm not going to re-render because of the render time.
The second image is very simple. Just some pines with the Alps in the background. It was just a test really; I wanted to see what Bigben's Alps ter looks like. Maybe someday I'll go back with more trees to pick from and try to actually make something of it.