TIME OF PLOWING SMALL-GRAIN STUBBLE. 



9 



As already stated, the percentages are computed on the dry weight 

 of the soil, and, as the weight of the soil in the first foot is less than 

 in those below, the percentage of moisture must be higher to indicate 

 an equal amount of water. For example, the percentage of moisture 

 on April 9, 1912, on plat A in the first foot was higher than for the 

 second, but the actual amount of water in each of the 2 feet was the 

 same. The weight per cubic foot of the lower 5 feet is nearly the same, 

 so that a comparison of moisture percentages is also a direct compari- 

 son of moisture content. 



DEPTH IS08 1909 1909 1910 1910 1911 1911 1911 1912 1912 1912 1913 1913 1913 1914 1914- 

 INFEET Jtug.27 /f/x-.J #«tzs #a*i7 du/./o /Tfr.B fiog/F 0ct30 for} /}„£.] Oetzs fynS Jl,/24 Octz /^af.24 Ju/20 



I 



2 



• 3 



►- 



a 



5 



6 



beam iunts of water available to wheat in each of the upper 6 feet of soil at 

 certain dates of sampling at the A I ron E ield Station, for the years 190S to l'J14, inclusive. Plat A is 

 lat B is fall plowed, and both arecontinu >u 1I3 1 ropped la spring wheat. 



mall percentage of moisture in any foot does not necessarily 

 ji thai the moisture was evenly distributed through that foot. It 

 containedin a few inches of one foot. The determina- 

 tions of October 30, 1911, show 4.7 per cent in the firstfoot of plat A, 

 of which was probably in the upper 8 inches. The soil is usually 

 if available moisture at the time the small grain is lt.tr- 

 ted. One exception bo this was plal A, on August 7, L912. The 

 imer precipitation had been so heavy thai .-ill the water in the 

 ; '.ii April 9, L912, bad not been needed in the production of the 

 crop. The spring sampling of April 7, L909, showed a little higher 

 moisture con ten 1 in plat I> than in plal A. The difference was in the 

 third and fourth feet. 



