322 THE MISSISSIPPI VALLEY HISTORICAL REVIEW 



dairying region, the spring wheat region, the corn belt, the hard 

 winter wheat region, and the northern portion of the mixed 

 farming zone where northern and southern agriculture meet 

 (the corn and winter wheat region). Historically the agricul- 

 tural map has ultimately assumed its present form because of 

 the operation of the many forces that made up what may be 

 called the American agricultural revolution.*" The history of the 

 various crops and livestocks, including their movement west- 

 ward until they came to dominate in their present centers of sur- 

 plus production, is a vital part of the subject. The changing ways 

 of farm management and the introduction of new and improved 

 varieties of crops and breeds of livestock and the efforts toward 

 diversification also have a large place in the history of agricul- 

 tural production. The series of articles on the historical back- 

 ground of the economic phases of the production and marketing 

 of the basic agricultural crops that appeared in the Yearbooks of 

 the Federal Department of Agriculture for 1921 through 1925 

 afford useful summaries, and they might well be taken as the 

 starting points of detailed studies.-^ L. B. Schmidt also outlined 

 the westward movement of corn and wheat,-- and there are also 

 a few valuable monographs like J, A. Hopkins' Economic His- 

 tory of the Production of Beef Cattle in Iowa, and J. G. Thomp- 

 son's Rise and Decline of the Wheat Growing Industry in Wis- 

 consin that point the way. 



The other instrumentalities of agricultural production and 

 rural life, other than land and management, namely, labor and 

 equipment, need consideration. The ways in which the inade- 

 quacies of the labor supply have been met, the hired man and his 

 wages, transient labor, etc., have hardly been mentioned, much 



20 Louis B. Schmidt, "The Agricultural Revolution in the Prairies and the Great 

 Plains of the United States," Agricultural Ili.tiory, VIII (193-4), 169-195. For a 

 more general statement, see the same author's " Tlic Agricultural Revolution in the 

 United Slates— 1860-1930," ScUnce (New York), LXXII (1930), 585-594. 



21 The articles appeared as follows: 1921 — wheat, com, beef, and cotton; 1922 — 

 timber, hogs, dairy industry, tobacco, and small grains; 1923 — sugar, sheep, forage 

 resources; 1924 — hay, poultry; 1925 — fruits ajid vegetables. 



22 Louis B. Schmidt, "The Westward Movement of the Corn-Growing Industry 

 in the United States," Iowa Journal of Ili-story and Politics (Iowa City), XXI 

 (1923), 112-141, and id., "The Westward Movement of the Wheat Growing Industry in 

 the United States," ibid., XVIIl (1920), 396-412. 



