roughages can be divided into three categories-dry, green, and silage. the most important of the dry roughages is hay. some types of legume hay are alfalfa, clover, lespedeza, soybean, and peanut. a legume is a plant in which certain bacteria can transform nitrogen in the air to nitrogen that plant can use. grass hay include timothy, orchard grass, bromegrass, bermuda grass, and other. the hulls of cottonseed, peanuts, and rice also fall into the category of dry roughages.