Now compatible with Open Cities (meaning that it should also be compatible with any mods affecting the surroundings of Whiterun area).
It only affects the vegetation, as per mod's description:
This mod adds pines in Whiterun and replaces the old textures of Whitrun with forest textures. The vegetation has been created so that it looks realistic.
This mod change ONLY Whiterun and no other cities or objects, which haven't a relation to Whiterun.