Here's another article on goats.
http://permaculturenews.org/20...
But again, I would say people seem to think goats will eat anything. They need browse to stay healthy. Teaching them not to eat desirable plants. A favorite thing for my goat to do was to get out of her pen and go to the neighbors' rose bush. The lady would hit her with a broom--goat take another bite, another swing with the broom, goat takes another bite, until I finally caught up with her and took her back home. I think the only way to teach a goat to stay out of the display roses, is to grow her some field roses of her own--that she is welcome to eat!
And, speaking of using animals as weeders, one thing I have noticed here in Alabama, is that kudzu fields can be cleared just fine by allowing cattle to graze the kudzu for a season. I have seen kudzu infested fields turned into productive gardens in one years time.