I wrote a program that replaces the block forests with a lot of individual trees.
The combination of faster hardware and the new fast tree object make it possible for this many trees run with a good framerate.
The way the program works is it removes the forest side polygons, lowers the forest canopy polygons to ground level, does a few tweaks, creates a new RGB file with lightened colors to be compatible with the noise maps (allowing gouraud shading), and then plants a bunch of trees on the forest locations now at ground level. It also creates a default-W.rgb and default-W.sec for use with the Winter season. Gotcha put code in the exec. to load these files for Winter but you have to change the option in the mapinfo.txt file for that to happen. Without doing that you'll see greenish looking snow. Maybe a change could be made in the exec. so the winter RGB file is loaded when winter is selected by the user interface .The Winter RGB file is all white colors. I've only tested on the Georgia map so far so I've restricted it to only run for the Georgia terrain.
You need to use "texture_colour=2" in eech.ini.
If you don't have the fast tree object I distributed with More_Puerto_Rico_Trees or GrandCanyon2 then you need the "import_tree_scene_and_object" otherwise you don't. It's the same thing.
Get it here:
My EECH Mods