Immediately after harvest the land is usually dry and easy to work.
The soil plowed at this time and left rough is acted upon physically by frost which pulverizes it, and chemically by rain and air which renders plant food available.
Insects are turned up and exposed to frost and birds.
A great number of weeds are destroyed and the land is more easily fitted for crops in the spring. Fall plowing should be done as early as possible, especially in the dryer regions, to catch all water possible. It is not advisable to plow sandy soils in the fall lest plant food be washed out of them.
When possible a cover crop should be put on fall plowed land where there is likely to be loss of plant food by leaching.
BARE FALLOW
The term "fallowing" is sometimes applied to the operation of plowing, and sometimes the land is left bare without a crop sometime after plowing; this is called "bare fallowing" the land.
Bare fallowing should not be practiced on all soils. It is adapted:
To dry climates and dry seasons where it is desirable to catch and save every possible drop of rainfall, and where plant food will not be washed out of the exposed soils by rains.
To heavy clay lands.