Bovie: NON-AVAILABLE WATER IN SOILS 283 
Number. | Amount of desiccation. Sheen oat i om ‘iste in fos aie ior he 
per cent. 
25n green -34 rs. 
250 .09 54. 
25p dry -05 98. 
4l dry -06 125. 
4m dry (partly) ats 52.5 
4n dry .09 90. 
40 wilted 25 Sa. 
4p dry (partly) Bs 79.5 
61 dry 14 
6m dry 09 128.5 
6n dry 09 I 
60 dry Ti 105 
6p dry 09 140 
The non-available water relations are more clearly represented 
by the graphs 1, 2, and 3. Graphs 1 and 2 are details of the 
sodium chloride and the full nutrient series, respectively. Graph 
3 is a combination of 1 and 2, enlarging the scale of the ordinate 
10 times, and indicating the determinations only in part. Re- 
ferring to graphs 1 and 2, it will be seen that, with but a single 
exception, the amount of non-available water in the soil varies 
with the amount of desiccation which the plant has experienced. 
Cultures in which the plants are just beginning to wilt have the 
most; and those in which plants have dried have the least. Also, 
even in the culture containing the highest percentage of non- 
available water, the soil solution represents a concentration of 
43 percent. That the plant actually lived in these high concentra- 
tions is shown by the fact that in some cases the plants were still 
green when the sample was taken. Further, cultures in which 
plants are completely wilted, 7. e., plants just beginning to dry, 
have about 0.1 per cent. of non-available water, regardless of the 
amount of salts in the culture. Drawn across graph number 3, is 
a line representing the amount of water which the several sets had 
when the concentration of the soil water had reached 6 per cent. 
It is to be noted here that the plants in the cultures were not 
exposed to free water containing 6 per cent. of salt. The 6 per 
cent. curve lies so low that all the water in the quartz was in the 
form of film water, before this concentration was reached. No 
data have been found regarding isotonic values in film-water, a 
TRecorded to nearest 1/100 per cent. only. 
