Relation of Nonavailable Water to Hygroscopic Coefficioit 69 
The moisture conditions of the soil at the death of the plants 
are shown in Table 16 and in figures 7 to 11. Figure 16 shows 
the condition of the plants on April 23 and on June 8. The roots 
separated from the different foot sections of the subsoil are 
shown in figure 17. 
Cylinder with no free water in the subsoil. — Cylinder XII 
was filled with subsoil containing 5.8 per cent total water. The 
three plants in this cylinder wilted on March 19 and two were 
removed. During the following week the single remaining plant 
grew a little but from March 19 on it wilted every day and growth 
had ceased entirely by March 26, its condition steadily growing 
worse until May 13 when it was practically dead. It was then 
harvested and the cylinder opened. The dwarfed plant is shown 
on the left of the upper row in figure 16. As in the case of the 
corresponding wheat cylinders roots had penetrated only a few 
inches into the first foot of subsoil and in this also a slight distil- 
lation of moisture seems to have taken place. The average 
amount of moisture in the subsoil was the same as when the 
experiment was begun. In the portion of the subsoil in which 
the roots had developed, no free water remained. The amount of 
water lost per gram of dry matter produced was very large, 
namely, 1315 grams. 
Cylinder with 4 per cent free water in the subsoil. — 
Cylinder XYI was filled with moist subsoil containing 9.8 per cent 
total water. The first signs of injury from drouth were observed 
on March 26. After this the plant made no growth but remained 
alive until killed by the high temperature of June 12. Even on 
May 27 the plant was green to a height of 8J inches above the soil 
in the cylinder. Roots had penetrated only to the fourth foot. 
In the fifth and sixth feet none were found and in these the mois- 
ture was as high as when the seed was planted. The surface foot 
was practically as dry as in any other cylinder, but the upper 
portion of the subsoil was as moist as that of XVIII and the 
lower portion was much more moist. This moist condition of 
the lowest foot and a half is to be attributed to the failure of 
the plant to develop roots to that depth, while the comparatively 
high percentage of moisture in the upper portion of the subsoil 
is to be attributed to the very limited development of roots in 
this portion. Under less trying conditions the plant might have 
lived for a considerable time altho it had long ceased to make 
any growth. 
Cylinder with 8 per cent free water in the subsoil. — 
Cylinder XVIII was filled with subsoil containing 14.1 per cent 
total water. The plant in this made a slow but normal growth 
