Excerpt from report summary: Nearly three-fifths of the land area of the United States is used to produce crops and livestock. More than one-fifth is ungrazed forest land; less than 3 percent is in urban and related intensive uses. Areas designated primarily for parks, recreational or wildlife refuges, and various public Installations and facilities account for about 5 percent. The rest -- 12 percent -- is mainly desert, swamp, tundra, and other land of limited surface use. One-fifth of the land area is classified as cropland, but not all is used for crops each year. In 1964, the acreage used for crop production totaled 335 million acres, or 75 percent of the cropland base. The total includes 292 million acres from which crops were harvested, 6 million acres on which crops failed, and 37 million acres of cultivated summer fallow. Of the acreage harvested, 31 million were irrigated. The acreage used for crops was 23 million fewer than in 1949 and 45 million fewer than a decade earlier.