36 AGRICULTURE IN THE SEMIARID GREAT PLAINS. 



These rotations would give the following acreages of each crop on 

 the farm each year: 



Acreages in different crops for farm of 6A0 acres, one-fourth under cultivation. 



THREE-YEAR ROTATION. 



53 acres summer-tilled. 



53 acres in winter wheat and 



potatoes. 

 53 acres in corn and rough 



feed. 



FOUR-YEAR ROTATION. 



40 acres summer -tilled. 

 40 acres in winter wheat 



and potatoes. 

 40 acres in corn. 

 40 acres in spring grain 



and rough feed. 



FIVE-YEAR ROTATION. 



32 acres summer-tilled. 

 32 acres in winter wheat and 



potatoes. 

 32 acres in corn. 

 32 acres in spring grain. 

 32 acres in corn and rough 



feed. 



In the southern part of the territory winter barley and in the 

 northern part winter rye may replace a part of the winter wheat. 

 No one of these systems, of course, could be followed on all farms, 

 but some one of them can easily be varied to meet almost any of the 

 local conditions. On the sandier lands summer tillage can not be 

 practiced and winter wheat does not do well. On such lands corn, 

 sorghum, emmer, and rye must be the main crops. 



In the best part of the area the five-year rotation will probably 

 give the largest net returns, while in the western part the three-year 

 rotation will best fit the conditions. It should be noted that winter 

 wheat and potatoes follow summer tillage in all rotations. That is 

 because summer tillage has proved more profitable for these crops 

 than for any others. Summer tillage has not proved profitable for 

 corn, and therefore this crop follows winter wheat. The thorough 

 cultivation which corn requires leaves the soil in good condition for 

 spring grain; in fact, many tests have given as good yields of spring 

 grain following corn as on summer-tilled land. Sorghum is the most 

 vigorous feeder and the most drought-resistant crop of all, and for 

 that reason is placed last in the series. Sorghum also dries out the 

 ground so completely that the following crop is entirely dependent 

 upon the rainfall of the current season, there being little or no avail- 

 able water left in the soil by the time the sorghum is mature. For 

 this reason any crop following sorghum is almost sure to give a low 

 yield unless timely and abundant rains occur. Following the sorghum 

 with summer tillage gives an entire season in which to replenish the 

 soil moisture before another crop is planted. 



If the manure is cared for there will be enough to give each field 

 a light dressing at least once in the rotation. The writer is well 

 aware that farmers in the dry country are generally afraid of manure, 

 but he is convinced that the trouble is mostly due to too heavy 

 applications. Manure should be spread as evenly as possible and 

 great care should be taken that no large bunches are left. The thinner 



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