According to the report of th« Land Utilisation Committee (18) appointed by the Secretary of Agriculture in 1921 there are approximately 231,000,000 acres of humid grassland pasture in the United States* This area has an average carrying capacity of about one animal unit per five acres. (An animal unit may be defined as the equivalent of a mature horee, cow er steer, five hogs, or seven sheep* ) In addition to the above it is estimated that there are 587,000,000 acres of arid and ee»iarid pasture and range, practically all of which ie located in the fleet* The productiveness of this area is low, however, about twenty- four acres being required for one animal unit. Considering the potential acreage of agricultural land in the United States as 1,734,000,000 acres (18), it thus becomes apparent that nearly one half of that area is new devoted to pasturage*