596 STATE BOARD OF AGRICULTURE. 



Before entering into the discussion of the foregoing data an explana- 

 tion as to tlieir form of presentation is necessary. The first column to 

 the left of each salt solution contains the lowering of the freezing point 

 of the solution alone; the second column contains the freezing-point 

 depression of the soil treated with the solution, and this freezing-point 

 depression is entirely due to the solution applied, as the amount of de- 

 pression due to the soil itself at that moisture content has been sub- 

 tracted. The third column shows the difference in the depression of the 

 solution before and after it was added to the soil. The fourth column 

 contains the percentage of change in the depression that the salt solu- 

 tion suffered in the soil ; and, the fifth column shows what percentage of 

 the original concentration of the salt solution went to increase the con- 

 centration of the soil solution. 



With these explanations, the above data showing the influence of the 

 application of soluble salts upon the concentration of the soil solution 

 in the soil may be considered. An examination of the figures in the fifth 

 column of the various salt solutions reveals many interesting and im- 

 portant facts. Starting first with KCl solntion it will be seen that from 

 about 65 to 98% of the original concentration of this salt solution went 

 to concentrate the soil solution. The concentration of the soil solution 

 increased to the greatest degree in quartz sand, kaolin, sand, and burned 

 soils, and least in clays and clay loams. 



Considering next NaNOg, it will be observed that on an average much 

 larger percentage of the concentration of this salt solution went to 

 augment the strength of the' soil solution of the various soils. The de- 

 gree of concentration varies from about 70 to 100%, but in the majority 

 of cases it lies between 85 and 90%. The magnitude of concentration is 

 greatest in quartz sand, koalin, sand, and burned soils, and smallest 

 in clay loams, and clays. 



The CaNOs solution increased the concentration of the soil solu- 

 tion of nearly all the diverse classes of soils, including the clay loams, 

 and clays, about 100%. This is indeed exceedingly interesting and of 

 great importance. 



The KNO3 solution augmented the strength of the soil solution of the 

 various soils considerably less than did CaiNO^), and NaNO, but about 

 the same as the KCl. It will be observed that the agreement in the re- 

 sults between these two salt solutions is remarkably close. 



The (NHJoSO^ solution increased the concentration of the soil solu- 

 tion of some soils very greatly while in others only a very small amount. 

 Thus, in quartz sand, kaolin, sand, burned soils, the greatest part if not 

 all of the original strength went to augment the concentration of the 

 solution of these substances, but in the clay loams, clays, etc., only a 

 small portion of the original strength of the solution was used for the 

 same purpose, amounting in some cases to only 35%. 



The K0SO4 solution increased the concentration of the solution of the 

 various soils, with the exception of quartz sand, kaolin, sand, and 

 burned soils, on an average still less than did the (NH4)oS04 solution. 

 An examination of the data shows that in some of the clay loams, clays, 

 only about 35% of the original concentration of the salt solution was 

 imparted to the concentration of the soil solution. For the majority of 

 the soils the value lies close to 50%. 



The increase in concentration of the soil solution produced by the 



