Azelea Trees Spawning on Top of Dark Oak Trees & Mushrooms instead of Replacing Them

In the dark oak forest biomes almost always when an azelea tree spawns it is on top of a dark oak tree or mushroom instead of replacing it, it just sits on top which is cool every now and then but after awhile it is odd. This is definitely a bug.  This also happens with jungles but not as often since jungles are a bit more spread out and less dense