Trees populators

Generate trees in the world

First read this tutorial on creating the tree blocks (leaved and wood)
End dimension
It's advised not to spawn the trees in the END dimension because it has some problems.
Vanilla trees bug
Sometimes trees will spawn with vanilla leaves, this is a known issue and I have no solution for this. Seems to be a Minecraft/Spigot bug, seems an event used by IA sometimes is not triggered.
Big trees lag
Big trees COULD cause some lag on generation, please use only small tree types.
Other problems