Voe. XI Washington, D. C., December io, 1917 No. 11 
MOVEMENT OE SOLUBLE SALTS THROUGH SOILS 
By M. M. McCook, Professor of Soils, and L. C. WheeTing, Instructor in Soils , Michi¬ 
gan Agricultural Experiment Station 
1 
INTRODUCTION 
That there is a tendency for soluble materials to be distributed from 
regions of high to those of lower concentration in moist soils is to be 
expected from our knowledge of the phenomenon of diffusion. More¬ 
over, it is generally recognized that the translocation is affected by 
moisture. One of us (McCool), while conducting soil cultural studies, 
has repeatedly observed that certain soluble salts when added to soils 
soon accumulate at or near the surface unless loss of water by evaporation 
is prevented. Moreover, it has recently been shown in our laboratories 
that the actual concentration of the soil solution induced by the addition 
of single salts required to inhibit the growth of higher plants, as well as 
to retard certain bacteriological activities in the soil, varies appreciably 
with different soils, which, of course, is to be predicted when we take 
cognizance of the exchange of bases that may result when salts are added 
to the soil, as reported by numerous investigators. Thus, during the pro¬ 
gress of our researches on the concentration of the soil solution and 
related subjects several questions with respect to the movement of 
soluble salts in soils, as well as changes in the composition of the soil 
solution resulting from the addition of various substances, have arisen. 
Although reports concerning certain phases of the subject have been 
obtained, a critical examination of available literature has led to the 
conclusion that additional well-controlled experiments under both 
laboratory and field conditions are desirable. On account of the funda¬ 
mental importance of this subject, the present status of the researches 
bearing upon it, and certain improved methods, it is being exhaustively 
investigated in our laboratories, as well as under field conditions. In 
this report, however, are presented results of some of our laboratory 
studies of the translocation of certain salts when added in varying 
amounts to soils of different texture and water contents, together with 
changes induced in the composition of the soil solution. 
(53i) 
Journal of Agricultural Research, 
Washington, D. C. 
la 
Vol. XI, No. 11 
Dec. 10, 1917 
Key No. Mich.—6 
