Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1910-06-07
Crop Rotation.

According to their method OF growth
and general effect upon the soil, field
crops may be divided into three classes
perennial grasses and legumes, culti-
vated crops, and small grains and un-
cultivated annual forage crops. The
best results are obtained by alternating
these three classes of crops with more or
less regularity, in place of raising one
kind continuously.
Perennial grasses and legumes, as a
class, are soil protectors, soil reviewers,
and soil builders. They leave a con-
siderable amount OF vegetable matter In
the soil, which by decay furnishes good
supplies of plant food for crops which
follow. Through several years growth
these crops develop rather deep, pene-
trating root systems which gather certain
mineral foods In the lower layers Of the
soil and leave them in the upper layers
when they decay. These decaying roots
also improve the physical condition of
the soil by opening it up and increasing
it's capacity to absorb and retain mois-
ture. As is we'll known, alfalfa, the
clovers, and other legumes not only
possess the good characteristics Of the
grasses, but, in addition, have the ability
Through symbolic bacteria) of actually
adding nitrogen to the soil from the air.
One of these legumes should by all
means be included in every rotation.
Cultivated crops, through the tillage
and cultivation they receive, aerate and
pulverize the soil and conserve the moist
ure. This results in conditions favor
able for the development of bacteria
which hasten the decomposition and
chemical changes which make plant food
available. These crops tend to deplete
the fertility rather rapidly and to reduce
the organic matter. Well cultivated
crops do not remove 80 much soil mois-
ture as the crops in the other classes.
Some grains and uncultivated annual
forage crops draw heavily upon soil fer.
tility and soil moisture. They reduce
the organic matter rapidly, especially If
the straw is all removed. Many soils,
after few years cropping with grains,
become finer in texture, more compact
and heavier to handle. They dry out
quicker than they used to, and often
turn over in Jumps and hard clogs when
plowed. The good tilth of virgin grass
lands is more or less completely restored
to worn out soils when they have been
put into legume or grass for suf-
ficlent length of time.
As general rule cultivated crops,
like corn and potatoes, should follow
the grass crops. They have the ability
to get their food under more adverse
than some of the grains
like barley and wheat, and the constant
stirring helps greatly to subdue the sod
and leave a supply Of easily available
plant food for the crops that follow.
The grain crops should come in be-
tween the cultivated crops and the grass
crops. The cultivated crops have de-
stroyed many weeds which might injure
the grains, and they have prepared plant
food and left the soil in good physical
condition. By the time several grain
crops have been raised the soil is again
low in available fertility and organic
matter, and is rather hard and compact.
The grass crops will largely correct
these conditions. II nurse crops are
used in seeding the land, the grain crop
comes in the proper place to be used for
this purpose. I'D. W. Frear, Colorado
Agricultural College, Fort Collins.