Hi Andy, interesting about rye, I agree about slugs!
If you want a winter windbreak you need something shrubby but root systems then spread into the growing space. One exception is Jerusalem artichoke whose stalks stand all winter. They do feed a fair way and suck out a lot of mositure but are productive, if you can eat them! (wind of the other kind). If your plot is large enough to sacrifice a strip, they could help, plant anytime before April.
