This mod is still in alpha version, and I will add more biomes etc, but for now, here it is.
Stuff in Alpha 1.0:
Frozone Biome: A biome with Icewood trees
Redwood Biome: A biome with tall reddish trees
Nightshade Biome: A biome with the rare Nightshade Tree
Autumn Biome: A biome that will or may already have colored leaves
Bittercress Flower: A rare flower with no use yet
The Mist: a transparent gas, also with no use yet