fill 
Research Bulletin \o. 3 
The production of dry matter for the water lost was very 
low — only one part for 1315 parts of water, or the equivalent of 
one ton of dry matter for 11.5 inches of rain. 
Cylinders with 4 per cent free water in the subsoil. — 
Cylinder XTY was filled like XIII, except that a moist subsoil 
with 4.2 per cent free water was used. After the first month the 
plants in this did better than those in XIII, but poorer than those 
in any of the other cylinders. On March 18, 2 of the 4 plants 
wilted and did not afterwards fully recover, altho they remained 
alive until the middle of May. The other 2 plants did not wilt 
until April 3, following three days of high temperatures in the 
greenhouse. Both recovered and on April 30 the one plant had 2 
tillers and the other 3; the latter died during the latter part of 
May, while the former put a spike part way out of the sheath but 
gave no promise of further development. It was already dying 
on June 11 — the day before that on which the temperature in 
the greenhouse rose to 124° F. Two days later this plant was 
quite dead, having formed no grain, and the cylinder was opened. 
The surface foot of soil contained no free water (really — 4.1 per 
cent) while the free water in the subsoil rose steadily from 0.0 
in the upper half of the second foot to 2.1 per cent in the lower 
part of the sixth foot, averaging 1.4 per cent thruout the sub- 
soil. Roots were found in all levels of the subsoil, but they were 
scarce in the fifth foot and only a very few small ones were found 
in the sixth foot. There was still an appreciable quantity of 
free water in the lower part of the cylinder, but the root de- 
velopment was not such as to permit of its rapid absorption. 
Except in the sixth foot the moisture content was below the wilt- 
ing coefficient. It is possible that under favorable weather con- 
ditions — cool, cloudy, humid weather — or with a more extensive 
root development the one plant might have formed some seed. 
The moisture content of the subsoil was still 1.4 per cent above 
that of cylinder V and 1.0 per cent above that of cylinder XIX, 
in neither of which the last plant had yet died, but was 1.2 per 
cent below the wilting coefficient. 
It is of interest to observe that the four plants did not all 
die. or even wilt, simultaneously, but that two acted independ- 
ently of the other two and of one another, as tho they drew their 
water supply from different parts of the soil column. This is a 
good illustration of the difficulty of attempting in the field to 
decide upon the moisture content of the soil corresponding to 
the wilting point or to the death point. One of these four plants 
continued to grow and develop for some 80 days after two had 
permanently wilted and these two continued alive for nearly 
two months after so wilting. 
