Nature Essence
From Feed The Beast Wiki
Nature Essence is an item added by Magical Crops. It is made by combining a magical seed with an item from nature, eg carrot, potato, pumpkin, cactus, lilypad etc.
Nature Essence can be used to craft Cactus, Vines and Lily Pad.
It can convert Cobble and Stone Brick to their Mossy versions.
With Podzol, Dirt and Mushroom it will produce Mycelium.
With Water Essence, it will produce 32 Wood. Different combinations can give Oak, Birch, Spruce or Jungle Wood.