FARM animals are wintered on fodder and root crops, supplemented by concentrates, that is, grain, milling offals, oil-seed residues, etc.; the fodder, roots, and frequently the grain also are home grown. The preservation of the fodder crops, for use in the winter, presents more difficulties than that of the other home-grown foods, and the quality of the product is very variable, depending on the kind of crop, its stage of maturity when cut, etc. The quality of the product is important, because it governs the amount and kind of concentrates that have to be purchased. The Science and Practice of Conservation Grass and Forage Crops. By Dr. S. J. Watson. In 2 vols. Vol. 1. Pp. xi + 415. Vol. 2. Pp. vii + 417–820. (London: Fertiliser and Feeding Stuffs Journal, 1939.) 2 vols., 30s.