While driving by Sears Point Raceway (Infinion) recently in Sonoma, I noticed large flocks of sheep grazing the grass and weeds on the edges of the racetrack property. Turns out there is a free range sheep grazing service Wooly Weeders, which provides the sheep to control weeds for vineyards and other large properties. Apparently, the sheep can be more efficient and more ecologically effective in removing surplus weeds and grass. A simple and old fashion innovation for the problems of mowing large areas.
Article on Sheep Grazing in Vineyards from the Chronicle