22 



Campbell's 1902 Soil Culture Manual. 



moisture, and the importance of having a compact condition of the lower 

 portion of the furrow slice to lessen the danger. Prof. King has shown, 

 by practical experiments, and all observation confirms his conclusions, 

 that in soil that is packed the moisture moves upward from a depth of 

 from one to four feet much more rapidly than in loose soil. It is therefore 

 important to have this packing when a condition of extreme drought is 

 reached, as it may be the one thing that will save a crop. 



It must be borne in mind that Prof. King experimented in packing 

 at the extreme surface, where nearly all the moisture that had moved to 

 this point was lost by evaporation, and that had the packing been done 

 just below the surface the contrast would have been much greater. This 

 fact should also be borne in mind, that Prof. King's experiments were 

 on the grounds of the Wisconsin college, where soil moisture is invariably 

 found all through the soil down to sheet water. Had the experiments 

 been made in our semi-arid region, the contrast would have been greater. 

 If we get our soil moistened here to a depth of four or five feet we have 

 exceeded by some distance the usual conditions, and this depth of soil 

 moisture would be sufficient to carry us any ordinary season in the success- 

 ful growth of crops. Had Prof. King's experiments been made with a three- 

 inch layer of loose soil mulch above the packed portion, they would have 

 shown a much greater increase of moisture at the point of 2 to 18 inches. 



All these facts in connection with the movement of moisture in the 

 soil, under different conditions of the soil, as indicated in the experiments 

 noted and the teachings of the most eminent students of soil physics, give 

 us the valuable lesson that the packing of the subsoil, or what may be 

 properly termed the root-bed, aids us in these important points; increas- 

 ing the water holding capacity of the soil facilitates the movement of the 

 water from below up to this point when it is needed, is conducive to a much 

 greater development of root growth; and still further, and quite as impor- 

 tant, enables us to utilize the entire soil, having no waste ground caused 

 by a loose or porous condition of the soil as shown in cut No. 5. 



This is so important that it may be stated again plainly, so that no 

 reader may misunderstand. The process of packing the under portion of 

 furrow or plowed ground creates three conditions to aid in carrying the 

 growing crop over long dry periods, namely: 



1. More water in the soil. 



2. A stronger capillary movement of water. 



3. More prolific growth of roots. 



Don't pack the surface; it increases the loss of moisture by evap- 

 oration. 



Less seed is needed in packed soil than in loose soil for the same 

 crop result. 



Pack the lower portion of your plowing the same day you plow, to 

 save the moisture. 



