The Greeley tribune., 1910-06-02
Crop Rotation

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According % their nethoo on
,.,.D, ana general erect upon the
Soil. field crops may b. divided INTO
three ulassos peronnta ErAsses ana
.Ifgumes cultivated crons ana small
grains and uncultivatei annual for-
.9ep crops The best rsI!ts are OBJ
fginod hy alternating these three
classes of crops with innre or less
regularity m place OF raiSins one
.knd continuously.
Perennial grasses an iegumes, as
q class. are soil prote, ors, soil re-
.uswrrs. and soil builder. They leave
n considerable amount OF vegetable
matter In the soil, whi %. by decay,
furnishes good supplies o.. plant food
rpr crops which folloV Through
several years growth Il ase crops de-
EJlop rather deep, pen -ating root
systems. which gather certain min
prll foods in the lower AYERS of the
soil and leave them In The upper
/ LAYERS when they decay These de-
|cayus roots also impro' the physi-
cal condition of the sol by opening
/ Il up and increasing IL opacity 10
absorb and retain mois sure. AS is
Well known, alfalfa. the lovers, and
other leEumes not only POSSESS the
good characteristics OF Ae grasses,
hut in addition, hav, The ability
Through symbolic bact r.a) OF ac-
mally adding nitrogen 90 the soil
from the air one of tlese legumes
should by all means be Included in
every rotation.
Cultivated crops. thro b the till
age and cultivation tn receive.
aerate and pulyerize Il soil and
conserve the moisture. This results
iu conditions favorable Tor the de-
yrlopmcut OF bacteria which hasten
the decomposition and chemical
change which make plant 'ood avail
able These crops tend TO deplete
the fertility rather rapidly and to re-
duce the organic matter, Wen cul-
tVated crops do not remo,, so much
soil moisture as the eros in the
other classes.
Small grains and uncu,, yated an
nual forage crops draw holyily upon
soil fertility and soil mos ure. They
reduce the organic mattar rapidly.
especially II the straw is al removed.
Many soils, after a few years crop
ping with grains, becom finer in
texture, more compact and heavier
to handle. They dry out quicker
than they used TO. and 0,ten turn
over in Jumps and hard Clods when
ploWed. The good tilth OF virgin
grass lands is more or less COM
pletely restored to worn out soils
when they have been put into n
legume or a grass for sufficient
length OF time.
As a general rule cultivaied crops.
like corn and potatoes. should fol-
low the grass crops. They have the
ability TO get their food under more
adverse circumstances than some of
the grains like barley aud wheat. |
and the constant stirrins helps |
greatly to subdue the sod md 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 destroyed many weeds which !
might injure the grains, md 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 mat |
ter, and is rather hard and compact. |
The grass crops will laEK..y correct |
these conditions. If n,Ese crops are !
used in seeding the iand. the grain |
crop comes in the proper place to |
be used for this purpose
d. w FREAR. /
Colorado Agricultural College. Fort |
Collins