Trees grow step by step instead of all of a sudden. First the wood, then the leaves.
More Details: As you know, trees in Minecraft are growing from now on. Meaning, you plant a sapling and after a bit of time has passed, suddenly there is a tree where the sapling stood (more info). This mod changes that. First a log is set (in place of the sapling), then a next one, and so on. So the growth of the tree can take a minute. You can configure the growth rate. And that's all this mod does. No more and no less.
Biomes O Plenty
Only required on Server.