plant food in, 63.
potato, 28, 29, 161.
porous, 38.
relation of to water, 39, 46.
relation of to plants, 23.
retentive, 38.
rhubarb, 28.
sandy, 27.
small fruit, 28, 29.
soft, 38.
sorghum, 162.
stiff, 38.
stony, 29.
strawberry, 28.
swamp, 30.
testing, 162, 215.
tobacco, 27.
tomato, 28, 161.
truck, 27, 28, 29, 161.
vegetable, 28.
water-absorbing power of, 40, 43, 46, 142.
water-holding power of, 44, 142.
watermelon, 28, 161.
wheat, 29, 30.

Soil water, 150, 151.
amount of used by plants, 40.
and farm operations, 156.
control of, 53.
form of, 48, 153.