is when it produces the best humus.
Dry vegetation buried in the ground is harder to rot
than green. The rotting of this vegetation helps along
in the destruction of insect eggs so that the work is com-
plete. It is a self-evident fact that if there is enough
fertility and the soil particles are arranged so that
fermentation is taking place in all parts of the seed bed
it is impossible for insect eggs to hatch, hence the
desirability of plowing under this vegetation while it is
in a gieen state.
Plowing to Kill Weeds
WEEDS, like the proverbial poor relations, are always
with us, and they always will be. The damage done
by weeds is roughly estimated at one billion dollars per
year. It can be easily diminished to a very small sum
if proper precautions are taken. One must study the
habits and characteristics of weeds for their destruction
in the same way that he must study the habits and
characteristics of the plant that he desires to grow.
Nature acts upon the principle of the survival of the
fittest. Therefore, the farmer must till his land to
bring about a condition that gives the crop he intends
to grow the advantage. He can hardly expect to do
this unless he understands the characteristics of both.
It would require an immense volume to treat the
peculiarities and habits of all weeds and how they can
be eradicated, and if a volume were written, in six weeks
it would not be complete because Nature is constantly
bringing forth new varieties of weeds with considerable
less gusto than man produces new varieties of grains.
For this reason farmers must not always expect to find
the answers to their queries written in a book. Indeed,
they will seldom be found there because climatic con-
ditions have just as much effect upon weeds as they have
upon legitimate plants. Nature does not distinguish
between the two. The distinguishing is done by people
whose existence depends upon the food qualities of the
plants they desire to cultivate.
80 THE OLIVER PLOW BOOK
A most vital reason why one should understand the
characteristics of weeds before attempting to eradicate
them is because plowing has a tendency to cultivate
certain types of weeds rather than kill them. Sorrel
and quack grass are two very common examples of this
type. All types of weeds that put forth a new sprout
from any root joint can be eradicated by plowing if the
ground plowed has the benefit of after treatment that
will keep the stems from becoming exposed to the sun-
light. The reason is the stems receive their nourish-
ment from the leaves which are exposed to the sunlight.
If it is possible to keep the top growth down so the leaves
cannot absorb the necessary light for sustenance the
plant naturally starves to death.
Those surface root weeds which can be quickly killed
by cutting or burying in the ground do not cause much
The three great rules to observe are first, prevent
weeds from going to seed; second, prevent weed seeds
from being sown on the farm; and third, prevent all
weeds from making a top growth.
Farmers must not expect to keep their weeds down in
the field when they permit them to grow in fence corners,
along road sides, in pastures and other uncultivated
fields because these seeds are carried by the wind, birds,
water, and animals to all parts of the field where they
are ready for a new start and in very favorable condition
for germination and growth.
Our scientists tell us that annual weeds, those which
grow from the seed each year, may be eradicated by any
method which starts germination and then destroys the
plant before it produces seed. Biennial weeds, or those
that live two years between the germinating of the seed
and the maturity of the plant, require an entirely dif-
PLOWING TO KILL WEEDS
A field plowed in July so as to completely bury the weeds in a corner
of the furrow. Wheat was planted in the fall.
The following year this wheat crop was harvested without any of the
weeds turned under the precious fall appearing in this stubble.
THE OLIVER PLOW BOOK
Result of a portion of a field plowed with the combined rolling coulter
and jointer attached to the plow.
ferent treatment. The habit of cutting the tops of
these plants is not always the most desirable method
because very many of them will put out new leaves and
produce seeds, consequently, if the cutting method is
practiced the tops must be cut sufficient times during the
season to prevent the plants going to seed. Perennial
weeds, or those that grow from the roots, are the most
difficult to handle. A method of cultivation that will
expose the roots to the surface, and prevent them start-
ing growth is the most successful.
In all these different types of weeds one striking fact
stands out. That is both weed and legitimate plants
require the gases from the air which must come in
through the leaves and stem. This being true the first
course in the destruction of weeds is to prevent this food
PLOWING TO KILL WEEDS
A portion of the field shown on page eighfy-two plowed with the same
plow without the combined rolling coulter and jointer. These tall
weeds were thick all offer the field when the ground was plowed prepar-
atory to growing this crop.
assimilating process. It is a difficult task to attempt to
do this work by hand in large fields. The work must be
done with tillage implements..
The first step is to fall plow as deeply as it is possible
for the plow to operate. The deeper the weed seeds are
turned under the better. Every leaf, stem, and all the
seeds must be turned to the bottom of the furrow. For
this reason it is unwise to disk such ground in the fall
before plowing it. Experiments have been tried which
proved beyond a question of a doubt that the action of
the disk harrow in ground of this kind has a tendency to
sow the seed rather than eradicate it, while leaving the
surface of the ground unmolested and turning all surface
trash completely under with a plow has rid a field of all
classes of weeds.
THE OLIVER PLOW BOOK
A field of tall weeds being turned under with a plow having a com-
bined rolling coulter and jointer attached.
The combined rolling coulter and jointer for this work
is the most valuable addition to the plow. This device
turns all the surface trash and weeds into the lower
* right-hand corner of the furrow. Turning them under
deep in this manner means that the new shoots which
the seed will send forth take additional strength and
nourishment from the root system before they can reach
the surface. This growth impoverishes the root, thus
the growth is retarded and the weeds' vitality weakened.
If the plowing has been done at the right time in the
fall the winter's freezing will come along and kill the
tender plants. If the weeds are of a variety that will
come up very soon after plowing, the infested field
should be plowed early in the fall and when the weeds
come to the surface and begin developing leaves, surface
cultivating of the ground with the weeder or disk harrow
PLOWING TO KILL WEEDS
77ie identical spot in the picture shown on page eighty-four taken the
following year. This field had no hand cultivation, simply that of a
one-row horse cultivator. None of the varieties of weeds turned under
appeared in this field.
will immediately destroy the weeds. The great trouble
with unsuccessful practices of this kind has been the
failure to carry the after work through carefully enough
to kill all sprouting weeds. Quack grass has been suc-
cessfully eradicated by this method but the operator
did not permit a single leaf or stem to develop. In one
instance the farmer, after plowing, kept up this cultiva-
ting operation from spring until fall. He wanted to
plant corn on that field but his greater ambition was to
kill the quack grass, so he kept cultivating until fall and
sowed the field to fall wheat, reaping a much better crop
than he would have had he planted corn, and he entirely
rid the field of quack grass.
The secret of his success lay in the fact that he kept the
stems and leaves from drinking in the sunlight to sustain
the roots. The result was the root system started to
rot as it will do with all weeds just exactly as it does
with other plants.
THE OLIVER PLOW BOOK
Sectional view showing weeds buried in the lower corner of the
furrow deep enough to prevent their getting a good growth in the fall
before the winter's freezing will fall them. If the same plowing were
done in the spring the crops planted above would sprout and grow before
the weeds could get a start.
In this weed killing process a farmer may often be
obliged to choose between the loss of his ground for a
year or the growth of such a crop as he can expect to
raise in a weedy field.
*This reference means when right-hand plows are used. When left-hand plows
are used the weeds should be in the lower left-hand corner.
Plowing Under Green Manure
ONE is often troubled as to the proper time to plow
under a green manure crop. The answer centers
around the quickness with which a crop is desired.
It is common knowledge that a green plant turned
under will rot quicker than one that has reached maturi-
ty, and is in a dry condition when plowed. Evidently
then, the time, if quick results are desired, is to plow
when the crop is in a green state.
Scientists tell us that the best time to plow under a
green crop, if it is clover or some other legume, is just
before the blossom shows signs of turning. The reason
is the stems and leaves are in the green, or sugar state
and contain more of the plant food elements than the
crop that has not reached this period of growth. Plow-
ing under a green crop any later than this means that
the plant has reached a fibrous and starchy condition
and is much harder for moisture to dissolve. Obviously
more time will be required to reach a state when fer-
mentation can set in.
The clover plant moves much of the sugar from the
leaves and stems into the roots and stores it there in the
form of starch for the winter. In this condition clover
is more resistant to decay, consequently, when plowed
late in the fall there may not be enough time for the
plant to decay before the crop is planted. For this
reason it is always advisable to plow clover under in
88 THE OLIVER PLOW BOOK
the green state. Regardless of the time of the year that
plowing is done, decomposition will proceed faster if the
matter plowed under is always green. Hence, the ideal
time for plowing under a crop of green manure would be
to do the plowing at a time of the year when the crop is
If the location is such that there is a scant supply of
rainfall a heavy green manure crop plowed under after
it reaches the starchy stage can ruin the following crop.
It has been known to do so in a great many cases al-
though it is a question whether the farmer, whose crops
were ruined, understood the reason for it.
To cut a heavy crop and leave it lying loose on the
ground before turning it under loses an immense amount
of organic matter. The principal object of plowing
under green manure is to put organic matter into the
soil, hence there is nothing gained by plowing under
vegetation if it is mowed and left standing on the field.
It is far better to plow under the green crop without
cutting it. In this way all the organic matter is placed
in the soil in the proper condition.
Spring plowing of rye sown in the early previous fall
is apt to cause trouble in the clay soils if the field is
pastured in the early spring and the ground happens to
be wet and later on when desiring to plow, the weather
turns off dry, because the ground is packed hard and
will not break into a friable condition. If rye is per-
mitted to grow until late in the spring and then plowed
under it is very likely to break up capillary connection
with the sub-surface and keep the ground so that it will
interfere very seriously with the crop from feeding on
what nourishment already is in the ground.
PLOWING UNDER GREEN MANURE 89
A problem arises when plowing stubble with the idea
of making fertilizer out of it when the ground is so dry
and hard that there is little opportunity for enough
moisture to come up from below to rot the stubble
turned under. Since moisture is the only means to rot
this turned over stubble it is absolutely necessary to
bring about a condition in the ground whereby moisture
can come up from below. Obviously then, plowing
should be done to see that the trash is buried as deeply
as possible on the bottom of the furrow in such a way as
to interfere as little as possible with the upward trend of
Fertilizer crops of all kinds must always be plowed
under with the idea of their becoming well rotted and
decayed before the crop is planted.
If the soil which the farmer desires to turn under is of
a loose, ashy-like composition and the rolling coulter
will not cut through the .vegetation, a condition is met
which is exceedingly difficult to handle.
Soil of this kind is always lacking in humus. The
time that one usually desires to plow these fields is when
they are dry and in the ashy condition. If a strict
watch is kept upon the rainfall, and the ground should
be moist at the plowing depth during the growing period
of the cover crop, the ground can be plowed when the
moisture is sufficient to hold the soil together. Every
man is the best judge of his own farm in this respect.
The reason for the ground being in the dry and ashy
condition is its lack of organic matter or humus.
The purpose of growing the green manure crop is to
put this organic matter into the soil. If the plowing is
improperly done and the crop poorly plowed under the
THE OLIVER PLOW BOOK
Burying fertilizer at this depth, ten inches in the ground, will do a
grain crop planted on the surface little or no good. Buried in this manner
manure will not stop the upward trend of moisture to any extent but if it
were scattered across the furrow bottom as is usually done the upward
trend of moisture would be stopped sufficiently to ruin a crop in a dry year.
greatest good cannot be secured from the cover crop.
This ashy condition cannot exist if the soil contains a
great quantity of organic matter, hence the very purpose
PLOWING UNDER GREEN MANURE 91
plowing under green clover is to accomplish is defeated
unless it is thoroughly covered when plowing.
The principal reason why farmers mow green crops
before plowing them under is because of their inability
to successfully cover them with the plow. With the advent
of the combined rolling coulter and jointer this difficulty
is overcome. This attachment on a plow will turn
under the rankest growth of green vegetation more
efficiently than dry vegetation can be turned under in
the ordinary manner.
WHEN one considers that different soils must be
plowed in a manner to accomplish the desired
results, it becomes self-evident that it is impossible to
lay down a certain set of laws or rules to determine what
constitutes prize plowing. The most beautiful job of
plowing on the surface is not proof that the ground
will grow the best crop.
Before a perfect job of plowing can be done the fol-
lowing requirements must be fully met.
Each furrow must be straight from end to end.
Back furrow must be slightly raised and all trash
The top lines of the furrows must be uniform without
breaks or depressions. The top of the furrow may be
slightly ridged. Ground must be thoroughly pulver-
ized from the top to the bottom of the furrow; no air
spaces anywhere in the furrow slices.
Trash must not be visible in the line of furrow and
should be buried in the lower right-hand corner of the
Furrows must be uniform compared one with another.
The depth of all furrows must be the same and con-
tinue a uniform depth.
Dead furrows must be free from unturned ground.
The above rules are recognized as the standard by
which plow contests are judged. It is obvious that
This picture of fall plowing and the two following were taken in the
same field, on the same day, the different appearances of the soil being
caused by the curvature of the mouldboards of the plows doing the work-
The soil was a clay loam. If the ground were to be left as plowed
through the winter it is obvious that this kind of plowing would be
better than either of the other two because being rough it would not
run together and become compacted by the spring thaws and rains.
This field can be easier worked into a seed bed than that shown above
but not so easily as that shown on page ninety-four, hence it would not be
regarded so good plowing for spring planting or immediate seeding as
the other two.
94 THE OLIVER PLOW BOOK
// this ground is to be seeded immediately it is plainly apparent that
it can be worked into an ideal seed bed much quicker than the two fields
shown on page ninety-three. However, if this ground is to be left for
spring planting and the locality happens to be one where there is a great
deal of snow and rainfall, the ground may have to be replowed on
account of the extreme mellowness making it apt to run together.
plowing to fulfill these requirements would not be so
good for crop growing in some sections as another type
of plowing that would far from fill these requirements.
Hence, it would be much better for those who are
deciding plowing contests to judge the quality of work
in accord with the results expected of the plowing.
Plowing being done primarily for growing crops it
would seem logical that the rules of plowing contests
should be worded so as to promote the kind of plowing
that will produce the best crops on the ground being
plowed. Sod plowing should not be judged as stubble
plowing; plowing for wheat should not be judged the
same as plowing for corn, etc.
The second rule, back furrow slightly raised and all
trash covered, is a good one to follow in clay and loam
soils. It is easy to understand how these requirements
This picture shows a job of plowing in a sandy loam soil. The
furrows are even in width and depth and laid to make an evenly plowed
field. The back, furrow is not raised enough so that it can be detected
from the other furrows.
This plowing won the first prize at a plowing contest. The soil was
of an exceedingly clayey nature, entirely different from the soil in the
field illustrated above, yet the plowing is very similar. The field shown
above Was plowed in the spring, while this field was plowed in the fall.
would utterly fail in plowing sandy soils on account of
their loose construction. As a matter of fact, the leveler
sandy soils are left on the surface, providing the surface
96 THE OLIVER PLOW BOOK
is loose, the less moisture escapes from them. Hence,
from a practical standpoint the plow bottom that leaves
sandy soils level after plowing is better for the soil than
one that leaves it ridged or crowned.
A much better way to judge plowing is to take a spade
or some other sharp cutting instrument into the field
and see what is happening at the bottom of the furrow.
If there are large air spaces and clods the plowing is
certainly poor from a crop producing standpoint. If the
bottom of the furrow is covered with trash so that the
upward trend of capillarity is interfered with it is also
equally bad plowing.
Plowing is good when the furrow slice is well pulver-
ized from top to bottom, large air spaces eliminated,
and the trash buried to interfere as little as possible
with the upward trend of moisture.
PHE bottom is the business end of the plow. Upon
1 its performance depends the quality of the seed bed
the farmer can prepare. Since the quality of the seed bed
determines very largely the start a crop gets it is obvious
that a plow bottom is the vital part of a farmer's equip-
ment. All the rest of the plow is merely for the purpose
of enabling the operator to make the bottom work
When one reflects upon what has been said in
Chapter V about different soil compositions, the
effect of humus, lack of humus, fertility, moisture, air
and heat upon plant growth the reason why one must
use a plow bottom adapted to that particular kind of
soil becomes plain.
Manufacturers have not yet been able to make any
one bottom that can be adapted to all these different
types of soil. This explains why farmers who have sand
and clay soils should have both chilled and steel bottoms
with entirely different shaped mouldboards.
Plow builders are doing their utmost to design bot-
toms that will approach the best work in all conditions
under which farmers plow. They have been remarkably
successful in building bottoms that will plow excep-
tionally well in all types of soils that have one or more
common characteristics but when the demarkation is
too pronounced it is necessary to change the shapes of the
mouldboards in order to properly stir the soil.
98 THE OLIVER PLOW BOOK
A knowledge of what constitutes good plowing is
necessary before one can judge whether the bottom is
particularly adapted to that soil. It does not matter
what type of soil a farmer is tilling, the conditions
necessary for plant growth must be the same. The
soil must be well pulverized and properly compacted so
that air and moisture can mingle in every particle and
recess at all times, whether the soil is sand, clay, loam,
muck, or any other.
It is reasonable to assume, in view of the entirely
different characteristics of soil, that clay would be
broken into clods with the same type of mouldboard
which successfully pulverizes sand.
The plow bottom is nothing more or less than a three
sided wedge. The cutting edge of the share and landside
are flat sides of the wedge. The mouldboard and upper
portion of the share are curved and made to invert the
earth. The curvature and length of the mouldboard
have to do with the pulverization of the soil.
The bluffer the mouldboard is the more rapidly it will
pick up the earth and turn it over. For this reason all
types of plow bottoms that are used in plowing the
looser soils are naturally bluffer than those used in
plowing soils that stick together such as clay. It
obviously follows from thes"e two extremes that the
types of mouldboards used for plowing loamy soil must
lean more toward the bluff as sand predominates and
toward the longer curve as clay predominates.
There are countries where it is necessary to plow clay
soils when they are wet because of excessive rainfall and
no frost. This calls for a peculiarly shaped plow bottom
that is not very well understood in other sections of the
PLOW BOTTOMS 99
world. This soil is nearly always of a waxy, putty
nature and holds water much the same as an earthen
basin. For this reason tiling or draining has never been
successful, hence a plow bottom to successfully turn this
soil must turn a furrow well over, yet let it stand on a
corner of the furrow slice and leave small crevices or
sub-surface ditches on the bottom between each furrow.
This gives excellent drainage so that the sharp top
corner of the furrow can soon dry and crumble, leaving
a few inches of soil on the surface that can be worked
to bring about the condition necessary for the right
mixture of air and moisture for plant growth.
Prairie sod is full of grass roots and decayed vegeta-
tion. This ground is plowed to start the decaying of
grass as rapidly as possible. The ultimate object of
such plowing, of course, is to put the ground in a con-
dition of tilth for the successful growing of crops. The
rotting of the grass being the first step the sod should be
plowed to bring this about in the quickest possible time.
In most soils the complete reversing of the sod is sup-
posed to smother the stems and leaves of the grass so
they rot and decay very rapidly. This must be done
in a way to prevent new stems from springing up.
The success of this process depends upon plowing the
ground at a season of the year when there is moisture
enough to start rapid decay or a much longer time than
should be necessary will be consumed in the complete
decomposition of the sod. The discussion on capillary
water explains why this is necessary.
The thing to remember is that regardless of the kind
of grass the plant must be prevented from putting forth
new stems and leaves which, as is mentioned in a pre-
vious chapter, all plants will do when air and moisture are