Value of Sods. - The character
of the sods is a faithful index of the condition of
the soil in any region adapted to grass. The value
of heavy sods to a soil cannot be overestimated.
They not only give to a farm a prosperous appearance,
but our country’s agriculture would be on a
much safer basis if heavy coverings of grass were more
universal. We do not hold the legumes in too
high esteem, but the emphasis placed upon their ability
to appropriate nitrogen from the air has caused some
land-owners to fail in appreciation of the aid to soil
fertility that may be rendered by the grasses.
One often hears the statement that they can add nothing
to the soil, and this is serious error. They add
all that may be given in the clovers, excepting nitrogen
only, and that is only one element of plant-food,
important though it be. A great part of the value
of clover lies in its ability to supply organic matter
to the soil and to improve physical condition by its
net-work of roots. Heavy grass sods furnish a
vast amount of organic matter which not only supplies
available plant-food to succeeding crops, but in its
decay affects the availability of some part of the
stores of potential fertility in the land.
Prejudice against Timothy. - Timothy,
among the grasses, is especially in disrepute as a
soil-builder, and yet its value is great. The
belief that timothy is hard on land is based upon
observation of bad treatment of this grass. There
is a common custom of seeding land down to timothy
when it ceases to have sufficient available plant-food
for a profitable tilled crop, and usually this is
the third year after a sod has been broken. The
seeding is made with a grain crop that needs all the
commercial fertilizer that may chance to be used.
Clover may be seeded also, and on a majority of farms
it fails to thrive when sown. If clover does
grow, the succeeding crop of timothy may be heavy.
If clover does not grow, the timothy is not so heavy.
The seeding to grass is made partly because a tilled
crop would not pay, and partly because a hay crop
is needed. It comes in where other crops cannot
come with profit, and it produces fairly well, or
very well, the first year it occupies the ground by
itself. With little or no aid from manure or
commercial fertilizer, it adds much to the supply of
organic matter in the soil, and it produces a hay
crop that may be made into manure or converted into
cash.
If the sod were broken the following
spring, giving to the soil all the after-math and
the mass of roots, its reputation with us would be
far better than it is. This would be true even
if it had received little fertilizer when seeded or
during its existence as a sod, not taking into account
any manure spread upon it during the winter previous
to its breaking for corn. But the rule is not
to break a grass sod when it is fairly heavy.
The years of mowing are arranged in the crop-rotation
to provide for as many harvests as promise immediate
profit. On some land this is two years, and not
infrequently it is three. Where farms are difficult
of tillage, it is a common practice to let timothy
stand until the sod is so thin that the yield of hay
is hardly worth the cost of harvesting. Then
the thin remnant of sod is broken for corn or other
grain, and the poor physical condition of the soil
and the low state of available fertility lead to the
assertion that timothy is hard on the soil. This
is a fair statement of the treatment of this plant
on most farms.
Object of Sods. - The land’s
share of its products cannot be disregarded without
loss. The legumes and grasses come into the crop-rotation
primarily to raise the percentage of organic matter
that the land may appropriate to itself within the
rotation. Some of the crops usually are for sale
from the farm. Most of the crops require tillage,
and that is exhaustive of the store of humus.
A portion of the time within the rotation belongs
to a crop that increases the supply of vegetable matter,
unless manure is brought from an outside source.
Sods lend themselves well to this purpose because
they afford some income, in pasturage or hay, while
filling the soil with vegetation. The tendency
is to forget the primary purpose of sods in the scheme,
and to ignore the requirement of land respecting a
due share of what it produces. Attention centers
upon the product that may be removed. The portion
of the farm reduced in productive power for the moment
goes to grass, while the labor and fertilizers are
concentrated upon the fields that are broken for grain
and vegetables. The removal of all the crop at
harvest, and probably the pasturing of after-math,
are the only matters of interest that the fields,
depleted by cultivation and seeded down to grass,
have for the owner until the poor hay yield and the
need of a sod for corn draw attention again to them.
Seeding with Small Grain. - The
usual custom is to sow grasses with small grain, and
there is much to commend it. The cost of preparing
the seed-bed rests upon the grain crop, and the conditions
are favorable to fall growth and winter protection,
if the seeding is made in the fall. Wheat and
rye are good crops with which to seed. In the
case of fertile land there is the danger that the
timothy will establish itself too well in a warm,
moist autumn to permit clover to get a foothold the
following spring, and clover should always be seeded
for the sake of fertility. In northern latitudes
clover cannot be seeded successfully as late in the
season as wheat should be sown, as it fails to become
well rooted for winter. The overcrowding of clover
by timothy is met in part by reduction in amount of
timothy seed sown with the wheat.
The oat crop is less satisfactory
for seedings to grass and clover. The leaves
near the ground are too thick, shading the young plants
unduly, and the late harvest exposes the grass and
clover when the season is hot, and usually dry.
Some reduction in the amount of seed oats used per
acre helps to save from injury.
Seeding in Rye. - When thin
land is desired for pasture, and available fertility
cannot well be applied, a sod may be formed more surely
by seeding with rye, using the rye for pasture and
a mulch, than, probably, in any other way. The
ground should have good tillage and then be seeded
to rye in September at the rate of six pecks of seed
per acre. Timothy and red-top should be seeded
with it, and in the spring red and alsike clover should
be added. Whenever the ground is dry enough in
the spring to permit the tramping of cattle without
injury, the rye should be pastured, and preferably
by a sufficient number of animals to hold the rye
well in check. When the usual time for heading
comes, all stock should be removed, and when heads
do appear, the growth should be clipped with a mower
and left as a mulch on the surface. A second
clipping will be required later, with cutter-bar tilted
well upward. When the usual summer drouth is past,
livestock can again be turned into the field.
This method is suggested only for thin fields that
have failed to make catches of grass, and that for
some reason cannot well be given the fertility that
all thin soils need. The application of lime
before seeding to the rye is an expense that usually
must be met in the case of such fields, and fertilizers
should be used.
Good Soil Conditions. - When
the grasses and clovers desired for a sod are sown
with small grain, there is competition between them
and the grain crop for fertility, moisture, and light.
The grain crop is the one that will produce the income
the following summer, and naturally is given right
of way. The amount of seed is used that experience
teaches is best for a maximum yield of grain.
Usually this gives a thicker stand of plants than
is best for the tiny grass and clover plants that
often are struggling for existence down under the taller
grain. If the farmer could see his way clear
to cut down the quantity of seed wheat or oats used
on a fertile soil, the catch of grass would be better,
but the small-grain crop is not very profitable at
the best, and the owner does not like deliberately
to limit it.
A greater amount of failure is due
to an inadequate supply of fertility. The grass
does not suffer so much from over-shading as it does
from starvation, both during the growth of the grain
and after harvest. The stronger grain plants
appropriate the scanty stock of available fertility,
and leave the grass and clover nearly helpless.
This condition is especially noticeable in dry seasons
when there is less opportunity to obtain food in solution.
Plants which are expected in another season to fill
the ground with vegetable matter are starved in the
beginning and die. Plant-food is needed, and should
be mixed with the soil when the seeding is made.
The fertilizer needs are discussed in another chapter.
When manure is available, it should
be spread on the plowed ground and mixed with the
surface soil. If a soil is thin, or heavy, or
light, the use of a ton of manure in this way can
bring greater returns than under any other circumstances
in general farming. It supplies some fertility,
and it puts the surface soil into good physical condition
for young plants. Land deficient in humus forms
a crust after a rain, and a tiny plant suffers.
A light dressing of manure, well mixed with the soil,
tends to prevent this hardening of the surface and
loss of water. There is no other form of fertility
that can fully replace manure, for either compact
or leachy land.
The probable need of lime has been
discussed in other chapters. Clovers and the
grasses want an alkaline soil, and there is waste of
money and time in seeding acid land. The lime
and the manure must not be mixed together in the air,
but both can be used when fitting land for seeding,
and both should be used if the need exists. One
should be applied early and be well disked into the
soil, and then the other application may be made and
covered with the harrow. The soil is an absorbent,
and the contact of manure and lime within the soil
only leads to immediate availability, which is desirable
in giving the grass a start.