Bark

1. Base with Dryad Bark
2. Wash with Agrax Earthshade
3. Wash patchy areas with Athonian Camoshade
4. Drybrush with Karak Stone

Leaves

1. Base with Deathworld Forest
2. Wash with Athonian Camoshade
3. Wash patches with Agrax Earthshade

You can highlight these up further with a lighter green (e.g Elysian Green or Nurgling Green ) but I like to keep terrain subtle so it doesn't distract from the more important miniatures on the board.

Ground

1. Base ground with Steel Legion Drab
2. Base Rocks with Mechanicus Standard Grey
3. Wash everything with Agrax Earthshade
4. drybrush everything with Karak Stone

Mushrooms (on Trees)

1. Base with Squig Orange
2. Wash with Fuegan Orange
3. Wash with Agrax Earthshade

Static Grass

1. Element Games own Autumn Grass