If You use a paint FX tree it has some animation on it so you can get it looking like its blllowing nicely (or use expressions etc to get it movinbg how you want it to. Heres an example of a tree and fur animated using some expressions
https://www.youtube.com/watch?v=qYZ4PkH9ruM
Not too sure how you would go about the fence as im not too sure what you want ti to look like, aybe have a ply with softbodies and springs???
"No pressure, no diamonds" Thomas Carlyle