Transforms the large flora (trees, mushrooms & cacti) to grow slowly from sapling to a large plant with branches and sometimes even fruits. Forests slowly regrow themselves and spread throughout the world. Trees grow around obstacles. Will die in the dark. Walking on leaf blocks will slow the player down, while falling on them will break the players fall. Thin branches on the other hand can be climbed. Trees compete for daylight (heavily forested areas will have taller smaller trees, trees with lots of space will be wide and tall).
Worldgen
Potions can be made to stop the trees from growing (for decorative purposes), and can turn a tree into a mega variant (jungle and spruce).
Alchemy