Ahaha, oops. Most probably the scenery was designed for FS2004, not FSX, and has rotate-to-user trees - a single picture that turns to face you (scenery was put together by Robin?

)
The rotate-to-user trick doesn't work with SP2; the trees get black boxes around them. I don't think that this is really resolvable - just a result of software made for FS2004 being used on FSX.

Getting rid of the trees though, you'd probably have to get in contact with the authors to find out which file does which, although someone here might know...

Alex