This will bring spring time to your game.
It replaces nothing and is easy to use.

I'm not good with textures, so I almost only used vanilla textures as a basis, with a few exeptions.

I only added flowers to the ground and all trees are edited. If you use a grass replacer or texture replacer for tree barks, it is still intact.
Not much to say... just try it^^

Autumn/Fall: http://www.nexusmods.com/oblivion/mods/47252
Winter: http://www.nexusmods.com/oblivion/mods/46618
Tropical: http://www.nexusmods.com/oblivion/mods/46118
Summer: See original game ;)