Herbalism gives oak leaves when it procs regardless of what leaf block you punch.
Herbalism should instead check for the ID of the punched block more closely to drop the correct leaves when it activates.
Edit: Leaves dropped also do not stack with standard oak leaves.
Herbalism should instead check for the ID of the punched block more closely to drop the correct leaves when it activates.
Edit: Leaves dropped also do not stack with standard oak leaves.