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.

To lands that are foul with weeds and insects.

To sour soils which are sweetened by exposure to air and rain.