36 
Research Bulletin No. 5 
by the recent rain. Frequently indications of this kind have 
been found, and. when there is sufficient water below, there may 
be some upward movement caused by a change in the temperature 
at the surface. We have, however, attributed these slight changes 
to nonuniformity of the soil or to experimental error, the scope 
of either of which is sufficient to cover almost any such difference 
found. 
In Table 11 are given the data obtained from sampling two 
fields at different times during the season of 1912. The lowest 
line of figures gives the amount of rainfall in inches during the 
period just preceding the date of sampling. It will be noted from 
the table that the sod land was very dry below the second foot 
at the time of the first sampling. The third foot shows an in- 
crease in the water content April 29 and the fourth foot at the 
following sampling. The following two periods, May 25 and 
June 10, show a slight increase in moisture in the fifth foot. 
After this date the soil water is used by the grass and the soil 
is not again moistened below the first foot. The moisture reached 
the lower depths in the sod land only during the period of fre- 
quent rains. 
The data given in the second portion of the table were ob- 
tained from a field adjacent to the sod land, which was in oats 
1911 and sown to cane 1912. This field was kept clean cultivated 
until July 3, when it was sown to cane. It will be noted from 
this portion of the table that the maximum amount of water 
shown on any sampling date in the upper six feet of soil was on 
May 11. It was not evenly distributed on that date. The upper 
three feet contained more than they could hold for any consider- 
able length of time. After May 11 the weather was dry, and only 
light showers fell until after the cane was seeded (July 3) and 
began using water. The water content of the soil shows a loss 
during this period. There is a gradual downward movement of 
water in the soil in this field from April 22 to June 29, at which 
date the lower depths contain more water than at any other 
sampling date during the season. The increase in moisture con- 
tent in the lower depths at this date was due to the excess water 
from above moving downward and not to additional water 
from rains. After July 26, the crop not only uses the rainfall 
that comes, but uses the water that was stored in the soil during 
the early part of the season. The samplings are too infrequent to 
show from what portions of the soil it was first used. The table 
also shows that the cane crop used water from the soil at a depth 
of six feet. 
