1913. 



PUBLIC DOCUMENT — No. 31, 



Table No. 3. — Showing the Pounds of Water Soluble Constituents in an 

 Acre of the Different Soils with Average Moisture Conditions {20 Per 

 Cent.). 



All of the abnormal soils are shown to contain more water 

 soluble salines than do the normal soils, although in two in- 

 stances the difference is not marked. The amount of the 

 various constituents which make up the total soluble salines 

 differs widely in the several samples, the range being fully as 

 great in the normal as in the abnormal soils. The amount of 

 potash and magnesia is greater in all of the abnormal than in 

 the normal soils. The other constituents — nitrogen, phos- 

 phoric acid, calcium oxide, sodium oxide and soluble sulfates 

 — are present in larger quantities in some of the normal soils 

 than in the abnormal, although this is not true when the aver- 

 ages are compared, as has been shown in Table ~So. 2. 



The wide variation in the amounts of the various soluble 

 constituents, and the fact that some of them are found in 

 larger amounts in the normal than in the abnormal soils, would 

 indicate that the injury was not due to the toxic effect of any 

 one constituent, but rather to the combined effect of the total 

 soluble mineral matter. 



A further study of Table Xo. 8 would indicate that the safe 

 limit of concentration of the soluble ingredients is around .5 

 per cent, on the basis of 100 parts of dry soil, or 12,000 pounds 

 per acre foot with normal moisture. On this basis it could be 

 assumed that sample A, which is listed in the table as a normal 



