72 CULTIVATION METHODS AND ROTATIONS FOE GREAT PLAINS. 



practiced. A rotation that seems well adapted to our conditions is as follows: Summer 

 tillage, winter wheat, corn, spring grain, cane. Summer till and sow winter wheat; 

 disk and fall plow the wheat stubble for corn the next year; disk the corn stubble for a 

 spring grain — oats, wheat, or barley; apply manure during the winter, disk in spring 

 and plow for cane, which crop completes the rotation. To practice this rotation a farm 

 should have at least five fields. This 5-year rotation gives winter wheat on summer- 

 tilled land to be sold as a cash crop, corn and spring grain to be fed or sold according 

 to conditions, and cane for forage. If the forage and grains are fed, there will be 

 enough manure to apply in the rotation, covering one-fifth of the land each year. 



In exclusive grain farming, which is a hazardous proposition at best, some crop 

 must be turned under to keep up the fertility. This is equally true whether summer 

 tilling be practiced or not. We have this year obtained very good results from green 

 manuring with rye and with cowpeas. The yield was not up to that on summer- 

 tilled land, but was nearly as large. In each case the crop was turned under and the 

 land kept well tilled for the balance of the summer, and the land sown to grain in the 

 spring. If this can be done with a reasonable certainty of success, it may be more 

 profitable than summer tilling. It gives much the same condition of the land as 

 summer tillage and at the same time enriches the soil by the addition of humus. In 

 very dry years it is doubtful if this will give as high yields as summer tilling, since there 

 will be hardly enough water to rot the crop turned under and give a good seed bed in 

 which to sow the next crop. 



We feel that the practice of summer tilling is and can be kept profitable by system- 

 atic rotation of crops in which summer tilling shall be used only occasionally. If used 

 without care it may prove very detrimental. If used judiciously it will tend to free 

 the fields from weeds and guard against total crop failure and to greatly extend the 

 winter wheat growing area. 



PRECIPITATION RECORDS. 



Table XXXI presents the precipitation records by months for all 

 stations reported upon in this bulletin, not only for the year during 

 which the tests were conducted, but also for the year immediately 

 preceding. A study of this table will give a general idea of the 

 climatic conditions prevailing at each station for each year of the 

 tests. It also furnishes some information concerning the quantity 

 of water which may have been stored in the soil from the previous 

 year. It should, however, be constantly borne in mind that the 

 character of the rains and their distribution through the month 

 greatly influence their availability to the crop. A large part of 

 torrential rains may be lost by run-off. On the other hand, when 

 the rains are less than one-half inch a day they may be almost entirely 

 lost by evaporation. Again, there may be a heavy rainfall during 

 the early part of the month, followed by a severe drought extending 

 through the remainder of that month and the major part of the fol- 

 lowing month, with heavy precipitation during the later days. 

 Under such circumstances the monthly precipitation for both months 

 may seem to be ample, although crops may have suffered severely. 

 This all goes to show that neither the annual nor the monthly precipi- 

 tation as here given furnishes a safe basis for judging the weather 



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