140 
FLORIDA STATE HORTICULTURAL SOCIETY. 
Mention has been made of the 
loss of capillary water by surface 
evaporation. The loss of water in 
this way is great, but it is pos¬ 
sible to very materially reduce this loss. 
This may be accomplished, as is generally 
known, by plowing and frequently stir¬ 
ring the surface. King, in Wisconsin, 
has shown that a piece of ground lost in 
seven days, in consequence of not having 
been plowed, no less than 9.13 pounds 
of water per square foot more than an ad¬ 
joining piece that had been plowed; an 
amount equivalent to 1.75 inches of rain, 
and to more than 198 tons of water per 
acre. Hilgard, in California, reports 
some investigations of moisture condi¬ 
tions in adjacent orchards differently 
treated in regard to cultivation. In one 
case investigated, two orchards of apri¬ 
cots were separated by a lane only, and 
the soils were identical; but one owner 
had omitted to cultivate while the other 
had cultivated to an extra depth in view 
of a dry season apparently impending. 
Table I shows the difference of the two 
fields in moisture content in July to 
the depth of six feet. This difference of 
244 tons of water per acre he regards as 
quite sufficient to account for the observed 
difference in the cultural results. These 
results were that on the cultivated ground 
the trees made about three feet of annual 
growth and the fruit was of normal size, 
while the trees on the uncultivated ground 
made barely three inches of growth, and 
the fruit was stunted and wholly unsal¬ 
able. Hilgard adds that, instructed by 
the season’s experience, the owner of the 
uncultivated orchard cultivated deeply the 
following season. His trees then showed 
as good growth and fruit as his neigh¬ 
bor's. Hilgard attributes the cause of 
this difference to the fact that in the un¬ 
cultivated field there was a compact sur¬ 
face layer of several inches in thickness 
which forcibly abstracted the moisture 
from the substrata, and evaporated it 
from its surface; while the loose surface 
soil on the cultivated ground was unable 
to take moisture from the denser subsoil. 
In diagram II I have undertaken to rep¬ 
resent this condition graphically. In the 
unplowed ground the capillary tubes or . 
openings, through which the moisture is 
brought from the deeper subsoil, extend 
all the way to the surface, and thus permit 
the evaporation of this moisture. 
Where the ground has been plowed, the 
capillary tubes are broken a few inches 
below the surface, and much of the moist- 
ture is thus prevented from escaping 
into the air. However, the movement 
of capillary moisture may take place in 
any direction, even downward, if the 
conditions are favorable. 
Note. —The diagram is necessarily 
very much exaggerated, and represents 
only very imperfectly what takes place 
in the soil. It- is not intended to convey 
the idea that cultivation will entirely 
prevent surface evaporation. 
At the Experiment Station we have re¬ 
cently determined the moisture in plowed 
and unplowed land with the results shown 
in table II. The plowed land selected is 
a cotton field that was plowed about 
March 24, and harrowed twice between 
that date and the time of planting the 
cotton on April 16. The unplowed land 
lies just across a path from the cotton 
field, and has not been plowed since last 
December. Samples for moisture deter¬ 
minations were collected on April 18, 24, 
28, May 1 and 7. (On the twenty- 
eighth of April, 0.86 inch of rain 
fell. On the thirtieth, 0.30 inch fell; and 
on May 6, 0.70 inch fell; making a total 
of 1.86 inches from April 28 to May 6.) 
We find here a difference of 164.66 
