It is for this reason that dry-farmers find it
profitable to plow in the fall, as soon as possible after
harvesting. In fact, Campbell advocates that the harvester be
followed immediately by the disk, later to be followed by the plow
The essential thing is to keep the topsoil open and receptive to a
rain.
Capillary soil-water
The so-called capillary soil-water is of greatest importance to the
dry-farmer. This is the water that clings as a film around a marble
that has been dipped into water. There is a natural attraction
between water and nearly all known substances, as is witnessed by
the fact that nearly all things may be moistened. The water is held
around the marble because the attraction between the marble and the
water is greater than the pull of gravity upon the water. The
greater the attraction, the thicker the film; the smaller the
attraction, the thinner the film will be. The water that rises in a
capillary glass tube when placed in water does so by virtue of the
attraction between water and glass. Frequently, the force that makes
capillary water possible is called surface tension.
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