Relation of Nonavailable Water to Hygroscopic Coefficient 35 
April 1, after which there was a steady improvement, the plants 
seeming fully recovered by April 10. From this time on no 
whitewash was used on the windows. 
Outside of the injury following the use of whitewash, condi- 
tions generally were quite favorable. No temperature record 
was kept. The evaporation from a free water surface in the 
greenhouse amounted to 12.2 inches between Mav 3 and Julv 31 
(Table 2). 
On account of the experience of the preceding year the ap- 
pearance of a crevice around the edge of the soil column was 
watched for from the time of planting and was found first on 
April 17. Altho the crevice could not be seen at the top of the 
mulch of dry soil, it could be detected by means of a long thin 
spatula pressed down at the edge of the cylinder. By means of 
this spatula the crevice was filled with surface soil. From that 
time on at intervals of a few days, all the cylinders were ex- 
amined for crevices and these, whenever found, were filled with 
surface soil, from one inch to two inches of loose dry soil being 
kept as a mulch on the surface of each cylinder. No crevices de- 
veloped in either of the unplanted cylinders III and VI, but 
sooner or later they appeared in each of the others. Later, when 
the cylinders were opened, the exact extent of these crevices was 
determined. 
By May 25 a hard crust had developed at a depth of from 1.0 
to 1.5 inches below the surface in I, II, IV, and VII. Later it 
developed in V and VIII also, but not in the unplanted cvlinders, 
III and VI. 
On March 13 the numbers of the tillers in I, II, and IV were 
9, 8, and 9 respectively. In order to determine the effect upon the 
soil moisture that would be produced by reducing the stand, two 
plants containing 0.439 grams dry matter were removed from 
II on March 22; on April 24, the four plants in II having 23 
tillers, 19 of these, containing 1.16 grams dry matter, were re- 
moved, leaving two plants with 2 tillers each. On the latter date 
the four plants in I had 27 tillers and the four plants in IV had 
31. The average height of the plants in I, II, and III was 12, 12, 
and 12.5 inches, respectively. The plants on eastern Nebraska 
soil had made much less growth than those on western Nebraska 
soil, having only 0, 3, and 3 tillers and being only 9, 9.5, and 12 
inches high respectively on April 24. Altho thruout the experi- 
ment the plants on humid soil made less growth, they were quite 
as healthy in appearance. Not until near the end of May did the 
thinning of the plants in II cause them to show any advantage 
over those in I and IV, but during the final month of their 
growth they appeared much more vigorous and they produced 
