A screenshot of the issue always helps.
(Also is this happening to regular trees nearby or the distant static trees drawn by MGE?)
_052_ Vurt's Grazelands Trees Bushy.esp
_053_ Vurt's Grazelands Trees.esp
I don't think you should be using both of these at the same time. That's unlikely to be the cause of your problem though.
Expanded Sounds (and the ES patches for graphic herbalism) is the first thing I'd try disabling.