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HIS publication is a revision and enlargement 

 of "A Graphic Summary of American Agri- 

 culture " contained in the 1915 Yearbook of the 

 Department of Agriculture, pages 329-403, and 

 Avhich was also issued as Yearbook Separate 681. 

 That publication was based largely on the 1910 

 census of agriculture, while this revision portrays 

 similarly the returns from the 1920 census. 



A comparison of the maps in this revision with 

 those contained in the previous edition will reveal 

 several significant shifts in crop production, nota- 

 bly the partial replacement of corn by wheat in 

 eastern Kansas and Oklahoma, and of cotton by 

 velvet beans and other crops in southern Alabama 

 and Georgia and in northern Florida. The in- 

 crease of improved land in the Northern Great 

 Plains Region and the nation-wide increase in the 

 nominal value of land, especially marked in the 

 Corn Belt, also deserve notice. 



Several new^ items were included in the 1920 

 census, notably silage crops, corn cut for forage, 

 annual legume hay, velvet beans, purebred live 

 stock, and farm facilities. Maps visualizing these 

 statistics appear in this revision, and several maps 

 relating to the size, value, ownership, and tenancy 

 of farms have been added. 



This revision also includes a series of maps 

 showing, in the most general way, the topography, 

 rainfall, length of frost-free season, soils, and na- 

 tive vegetation. These physical factors exert a 

 dominant influence in directing agricultural de- 

 velopment, and explain in large measure the geo- 

 graphic distribution of the crops and live stock. 



The author wishes to acknowledge the valued 

 assistance and advice of R. G. Hainsworth and 

 E. A, Dacey in drafting the maps and graphs. 



