other Chicken Trees

I was on my survival world, on a chicken/apple hunt (feathers for arrows, apples to make golden). Anyways, I heard a bunch of clucking coming from the top of a tree. I thought, "Yeah, lots of chickens, lots of feathers." So I started chopping down the tree. A chicken popped out of one of the wood blocks. They didn't fall from above it (there were leaves), it spawned right out of the block. I said, "Dafuq?" I killed the chicken and continued cutting down the tree. Two more chickens came out of the wood, not from above it. So I found a legendary chicken tree! It was a normal tree, that grew quite big for one. And none of the chickens dropped feathers. I have NO mods at all. Tried some (minimap, Mo' Creatures, Tornadoes and weather, etc.) them, but none worked.

So, anyways, have you guys ever found any chicken trees?

Probably some rare glitch or something, chickens and trees have no relations at all.

Normally glitches are bad. In this case..........