AGRICULTURE - IN THE UNITED STATES Canada and the United States are one agricultural unit. They produce more than one-fourth of the world's wheat supply, nearly three-fourths of the corn and more than one-third of the oats. They produce nearly one-third of the total grain supply, including rice. The United States is the most important food-producing area under one government. There are no trade barriers within the area. The population is fairly homogeneous and highly pros perous. This combination of circumstances provides the basis for a highly developed agriculture. It produces one-half of the world's cotton, two-thirds of the corn, one-fourth of the oats, one-fifth of the wheat crop and has about one-fourth of the hogs and one-tenth of the cattle.
Population.—According to estimates of the bureau of the cen sus, over one-half of the white population of the United States came from the British Isles and seven-eighths from northwestern Europe (Table I.). It is often stated that the American population