Took me over a week to create (not render)
There were a few things though I used to cheat to shorter render times
I used a leafy crown shaped billboard with a leaves picture from leaves that would origionally would be on there but file size was going up like no tommorow and would’ve taken longer with real leaves.
I used a plane to generate shadows for the 1000’s of blades of grass in their little patches cutting render time tremendously.
I also have to something that went wrong with the image and could be a bug in blender.
Images seem to increase their alpha value if they go farther into the fog. Note the trees in the very edge of what’s visible.