Campbell's 1902 Soil Culture Majsual. 



37 



increased quantities of moisture, even in the more humid sections of Wis- 

 consin. Had these observations been made in the semi-arid belt, with the 

 same persistent cultivation as applied by King, the difference would have 

 been three or four times the amount noted above. It is a fact, that hold- 

 ing the moisture near the surface of the soil during the heated portion of 

 the season causes a complete decomposition of the partially decomposed 

 vegetable matter which is found in large quantities throughout the sur- 

 face soils in the semi-arid west, and passing it on to the stage known as 

 humus, thus increasing both the fertility of the soil and its water holding 

 capacities. At the close of Professor King's remarks on this subject, he 

 says: 



••In very wet climates, or more especially in those which have heavy 

 rainfall outside the growing season, so that excessive percolation and loss 

 of plant food through drainage is large, summer fallowing in broad fields 

 cannot be recommended. But in dry countries where the loss of plant 

 food through drainage channels is small, and sometimes practically noth- 

 ing, broad field summer fallowing may prove decidedly advantageous, 

 because with the deficient rainfall there may not be moisture enough to 

 mature a paying crop, and at the same time develop a sufficient store of 

 plant food from the native fertility of the soil to meet the demands of the 

 next season,' 



In this assertion Prof. King is very modest, but he does bring out 

 some very important points which, with us. are vital in the semi-arid belts, 

 and mean much in future results. ■ The summer fallow idea in mind by 

 Prof. King does not anticipate very much cultivation. While in the sum- 

 mer culture, of which we have outlined, we have been able to store the 

 waters to a depth of nearly five feet in one season's cultivation, where 

 adjoining fields having received ordinary cultivation were practically dry. 

 While in South Dakota in '86 and '87, 1 practiced the summer fallow idea as 

 referred to by Prof. King, simply plowing in June, turning under a liberal 

 growth of weeds and. cultivating the field once afterwards. This field went 

 into the winter with very little, if any, more moisture than the adjoining 

 fields that had been cropped, and the increased yields both seasons were 

 only from ten to twenty per cent., the difficulty being a lack of cultivation or 

 effort to retain the moisture throughout the entire season. More cultivation 

 is needed in the higher and dryer sections than in Wisconsin. It is my 

 opinion, based on practical results and observation of conditions similar to 

 those in Western Kansas, that by the summer culture plan, storing the 

 water the entire season, and raising crops the following year, much larger 

 average crops may be grown than the present average in Iowa or Illinois. 

 In fact, we do not believe we overdraw, when we say that in the more arid 

 portions of the semi-arid belt by the summer culture plan, only cropping 

 every other year, we can raise more wheat in ten years than can be grown 

 in the more humid portions of the belt in ten consecutive crops by the 



