Custom Trees and Decaying Leaves

I have searched, and searched, the forums on decaying leaves on custom trees, and still cannot fix them. I have even made a mod before for a newer version of Minecraft and it worked. This version I am currently making a mod for is version 1.12.2. 

I have tried everything I know and the leaves still decay. I tagged the leaves as 'leaves' and the logs as 'logs.'  The game recognizes the leaves but not the logs.