668 



STATE BOARD OF AGRICULTURE. 



Considering the results at the conclusion of the ten-day period it is 

 seen that with the exception of two samples all the soils stored at 25 °C 

 showed an appreciable increase in the concentration of the solution. Of 

 the sain])les innintained at tlie low temperature several failed to show 

 an appreciable increase in the soluble salt content, it is noteworthy 

 that the increases in concentration of the solution of soils kept in ice 

 are much smaller than those of tlie samples maintained at 25°G. 



After tliirty days a general tendency for the concenti-ation <»f (he soil 

 solution to be less was observed in tlie samples stored at both leni])ci;i- 

 tures. There are more exceptions to this in the series maintained at the 

 low than at the higher temperature. The samples held at the low tem- 

 perature on the whole showed a lower average concentration of the soil 

 solution than those placed in the 25° C chamber, but due to the failure 

 of a number of the samples maintained at the low temperature to decrease 

 in soluble salt content between the ten-day and thirty-day periods, there 

 are a nund>er of cases where this is not true. 



The results obtained from studies of the Lenawee county soils at the 

 close of the thirty-day period are to be found in table 29. 



TABLE 29. — EFFECT OF TEMPERATURE ON I'HE RATE OF SOLUBILITY OF VARIOUS 



SOILS. 



Lenawee County Soils. 



Description of sample. 



Silt loam, cultivated. . . 



Silt loam, virgin 



Silt loam, cultivated. . . 



Silt loam, virgin 



Medium sand, cultivated 

 Medium sand, virgin. . . . 

 Clay loam, cultivated. . . 



Clay loam, virgin 



Sandy loam, cultivated. . 



Sandy loam, virgin 



Medium sand, cultivated 

 Medium sand, virgin .... 

 Silt loam, cultivated .... 

 Silt loam, virgin 



After 30 days. 



25 °C. 



Depres- 

 sion. 



.059 

 .035 

 .058 

 .027 

 .074 

 .015 

 .039 

 .034 

 .056 



.022 

 .050 

 .055 



Parts 



per 



million. 



1 ,475 

 875 



1 ,450 

 675 



1 ,850 

 375 

 975 

 850 



1 ,400 



' '550 

 1 ,250 

 1 ,350 



Low 

 temperature. 



Depres- 

 sion. 



.014 



.012 

 .013 



.019 



.020 

 .008 

 .027 

 .006 

 .021 



.017 



Parts 



per 



million. 



350 



300 

 325 



475 



500 

 200 

 675 

 150 

 525 



425 



After thirty days with one exception the samples stored at 25° C 

 showed considerable increases in soluble salt content over that which they 

 contained at the beginning of the experiment, while the difference in the 

 freezing point lowerings of the soils maintained at this lower temperature 

 did not differ markedlj^ from the originals. 



