Please help me with a glitch.

[Noisy Pants]

I can't add a picture for some strange reason, -error 200, so I'm linking the screenshot. This tree sprouts in the air and grows while floating and nothing I do makes it go away.
Floating Growing Tree Image

 

[BadZombie]

I had the same issue while playing on my old dedicated server. I built near to trader Jen, 2-3 blocks away from the trader protection zone and after I felled the trees the mesh still remained as shown in your photo.
Restarting the server did nothing. I managed to get rid of one of them somehow by swiping at thin air near it - maybe they have a reallllly small hit box? But in the end I put it down to a bug and moved locations.