New trees that spawn in Savanna drop wrong sapling and are unable to be reproduced

The new biome, Savanna, has these new trees that generate in them. They are made out of jungle wood, and oak leaves. When cutting down one of these new trees and the leafs start to deteriorate, they drop oak saplings. When trying to grow this sapling in the Savanna biome, it just grows a normal oak tree. And in the creative menu, there are still only 4 saplings.

Maybe I am missing something, but it appears as if it is impossible to grow these new trees yourself.

I'll provide a picture of the new tree.