480 
Journal of Agricultural Research voi. xiv, no. ™ 
soil and the much greater difference between the ratios in the surface 
layers of these and those in the exposed subsoil appear at least partly 
due to the differences in the proportion of organic matter. 
Under the climatic conditions of the locality more significance is to be 
attached to a statement of the amount of growth water than that of the 
free water in the case of corn, while the reverse holds true for grass fields, 
but neither of these is as satisfactory as a statement of the hygroscopic 
coefficient, together with the ratio of the moisture content to this. 
The distribution of free water in the surface foot assumes characteristic 
forms, dependent upon the preceding weather conditions and the presence 
of a plant cover. 
The moisture relations indicate that as a source of mineral nutrients 
the upper half of the surface foot may be more important than the lower, 
but this is due to the depth of penetration of rains and not to the depth 
of the plowline, nor to the distribution of the roots. 
LITERATURE CITED 
(1) Alway, F. J., and McDole, G. R. 
1916. THE LOESS SOILS OE THE NEBRASKA PORTION OE THE TRANSITION REGION. 
i. hygroscopicity, nitrogen and organic carbon. In Soil Science, 
v. 1, no. 3, p. 197-238, 2 fig., 3 pi. Literature cited, p. 70-71. 
00-- 
1917. relation oe the water-retaining capacity oe a soil to its hygroscopic 
coeeeicient. In Jour. Agr. Research, v. 9, no. 2, p. 27-71, 4 fig. Litera¬ 
ture cited, p. 70-71. 
( 3 ) - 
1917. RELATION OE MOVEMENT OE WATER IN A SOIL TO ITS HYGROSCOPICITY AND 
initial moistness. In Jour. Agr. Research, v. 10, no. 8, p*. 391-428, 2 fig. 
Literature cited, p. 427-428. 
(4) -and Rost, C. O. 
1916. THE LOESS SOILS OE THE NEBRASKA PORTION OE THE TRANSITION REGION. 
IV. MECHANICAL COMPOSITION AND INORGANIC CONSTITUENTS. In Soil 
Science, v. 1, no. 5, p. 405-436, 2 fig. Literature cited, p. 435-436. 
(s) - McDole, G. R., and Rost, C. O. 
1917. THE LOESS SOILS OE THE NEBRASKA PORTION OE THE TRANSITION REGION. 
vi. the relative " rawness '’ oE the subsoils. In Soil Science, v. 3, no. 
1, P* 9 ~ 35 > 4 fig*, 9 P 1 - Literature cited, p. 34-35* 
(6) Briggs, L. J-, and Shantz, H. L. 
1912. the WILTING COEEEICIENT FOR DIFFERENT PLANTS AND ITS INDIRECT DETERMI¬ 
NATION. U. S. Dept. Agr. Bur. Plant Indus. Bui. 230, 83 p., 9 fig., 2 pi. 
(7) U. S. Department of Agriculture. Weather Bureau. 
1915. national weather and crop bulletin, 1915, no. 7, 4 p., 5 charts. 
