502 



FARM MANAGEMENT 



inches. 1 Holding moisture in the soil in this part of 

 Kansas is a very different problem from conserving mois- 

 ture in Dakota. Figure 115 shows the lines of equal rainfall 

 and lines of equivalent rainfall for part of the Great 



FIG. 115. Lines of equal rainfall in black. Dotted lines pass through 

 places having a rainfall equivalent to 15 and 20 inches, respectively, 

 on the Canadian boundary. 



Plains region. Fifteen inches of rainfall is more effective 

 in North Dakota than 20 inches in Texas. 



307. Winds. The winds also affect profits. In semi- 



J U. S. Dept. Agr., Bureau of Plant Industry, Bulletin 188, p. 18. 



