SaplingsAnywhere + Beta alien trees!
Plant saplings anywhere and everywhere. As a bonus it adds 2 removed alien tree types, one of which had only wood, and one which was a mix that I separated into leaf and stems. Saplings can be placed anywhere but they still need a floor and to actually sprout. BUT fun thing is other objects dont count in that space, so you can for example place them on platforms, clipped into one another if you want. Good for landscapping!