Seed-mixtures.--When grass is wanted for_Crops and Methods for Soil Improvement

clovers and timothy compose the greater part of a desirable mixture

wherever the clovers and timothy thrive. Probably this condition always

will continue. The clovers are needed to supply nitrogen to the soil

and to put protein into the hay for livestock. They give way, in large

part, or entirely, the second year. Alsike is more nearly perennial

than the red which practically lasts only through its second season,

when its seed crop has been made, and its function performed. The sod

is chiefly timothy in the second season. A little red-top is desirable,

and the percentage should be heaviest for quite wet land or very dry

land. When fertility is the first consideration, and the sod is left

only two or three years, the following mixture is good, and is for one

acre:

Red clover 10 pounds

Alsike 2 pounds

Timothy 8 pounds

Red-top 2 pounds

When a mixed hay is wanted the first year, the following mixture may be

found better for the purpose:

Red clover 6 pounds

Alsike 2 pounds

Timothy 12 pounds

Red-top 2 pounds

Mammoth clover seed may be substituted for the red without change in

number of pounds.

The amount of timothy and red-top in the second mixture suggested calls

for a liberal supply of plant-food, and this is true of any heavy grass

mixture. If fertility is not present, the seeding of grass should be

lighter, but the clover should not be less in amount for a thin soil

than for a good one. The question of fertilizers is discussed in

Chapter XX.

CHAPTER IX

SODS FOR PASTURES

Permanent Pastures.--There is a large total area of land that can be

brought into profitable production of food only by means of pasture

grasses. A small part is too low and moist for tillage, but a larger

part is too rough or too infertile. It can be made to yield profit in

grasses that are harvested without expense by animals. The grasses

afford feed and at the same time protect the soil from waste. The

efficiency of much pasture land is kept low by poor stands of grass,

the encroachment of weeds, bushes, and briers, close grazing, and the

failure to supply fertility. When making a sod for mowing, the aim is

to select varieties of plants that mature near the same time. Pastures

need varieties maturing at different times, and this is a matter under

control when temporary pastures are used. Permanent pasture land soon

becomes occupied by the grasses best fitted to soil conditions or most

able to crowd other plants.

[Illustration: Good Pasture Land in Chester County, Pa.]

Seed-mixtures.--Several varieties of grasses should be used when making

a sod for grazing. They occupy all the surface more quickly and surely

than a single variety, and the pasturage is better. The character of

the soil determines the character of the mixture in large measure. When

land can be well fitted, a heavy seeding is best, but the cost is

nearly prohibitive for thin, rough lands. A brief description of the

leading pasture grasses east of the semi-arid region, and north of the

gulf states, is given:

_Blue-grass._--No other pasture grass equals Kentucky blue-grass

wherever it thrives. It makes a close sod, preventing the growth of

weeds and withstanding tramping, and contains a high percentage of

protein. While it is best adapted to limestone soils, it is grown with

success on clay land outside of limestone areas. It is slow in making a

heavy sod, as a rule, and partly because the seeding is too light on

account of low germination. The rule is to seed with timothy and other

grasses which furnish the greater part of the pasturage for two or

three years. When seeded alone, 20 to 30 pounds of seed per acre should

be used. It may be seeded in the spring or fall, and preferably in

August or September.

_Timothy._--In a mixture of pasture grasses timothy has a place

wherever it thrives. It is not naturally a pasture grass, standing

grazing rather poorly, but it makes a large amount of feed quickly. The

grass is one of the poorest in protein, and the pasturage gains much in

quality when the timothy gives way to blue-grass, as it will in two or

three years if the latter has favoring soil conditions. In most

mixtures it is given a leading place. It may be sown in the spring, but

preferably in the fall, and 15 pounds of seed will be found

satisfactory, when seeded alone.

_Red-top._--If red-top were as palatable to livestock as blue-grass, it

would have one of the most prominent places among our pasture grasses.

It is valuable anyway, thriving where land is too acid for blue-grass

or timothy, or too thin. It is adapted to wet land, and yet is one of

our surest grasses for dry and poor land. It makes a sod that lasts

well, and yields better than most other grasses. Notwithstanding its

lack in palatability, it should be in all pasture mixtures for soils

not in the best tilth. When used alone, 15 pounds of seed per acre

should be sown. The seeding may be made in spring or fall.

_Orchard Grass._--In most mixtures recommended for pasture orchard

grass has a place, but it should be a minor one. It makes early growth

in the spring, which is a point in its favor. It stands shade and also

drouth better than some other grasses, but is not at home in a poor or

wet soil. It grows in bunches, and becomes unpalatable if not promptly

grazed. It needs crowding with other grasses when grown for pasturage.

When seeded alone for hay, 30 pounds of seed per acre may be used.

_Other Seeds._--There are other grasses often recommended, but they

have no wide acceptance. Meadow fescue is a palatable grass that would

be used more often in pasture mixtures if the seed were not high in

price. All land seeded for grazing should have some clover sown for

sake of soil fertility. The alsike remains longer than the red or

mammoth, and is better for undrained, thin, and acid soils.

Yields and Composition of Grasses.--The Ohio station has compared the

yields of various grasses and their composition. The following table is

arranged from its data, as given in Bulletin 225:

+-----------------+----------+---------+----------+

+-----------------+----------+---------+----------+

| Timothy | 3.49 | 6.38 | 223 |

| Blue-grass | 2.18 | 10.12 | 221 |

| Red-top | 2.81 | 8.53 | 240 |

| Orchard grass | 2.19 | 7.81 | 171 |

| Meadow fescue | 2.10 | 8.97 | 188 |

+-----------------+----------+---------+----------+

Suggested Mixtures for Pastures.--For ordinary conditions, Williams

suggests the following mixture for an acre of land:

Blue-grass 10 pounds

Timothy 6 pounds

Red-top 6 pounds

Orchard grass 4 pounds

Red clover 4 pounds

Alsike clover 2 pounds

For use on rather wet lands, and especially off the limestone, he

suggests:

Red-top 12 pounds

Blue-grass 8 pounds

Timothy 4 pounds

Alsike clover 4 pounds

Hunt recommends the following as a basis, to be modified to suit

varying conditions:

Timothy 15 pounds

Kentucky blue-grass 10 pounds

Meadow fescue 2 pounds

Red clover 4 pounds

Alsike clover 3 pounds

White clover 2 pounds

The Cornell station recommends the following for good land:

Timothy 8 to 12 pounds

Kentucky blue-grass 4 pounds

Meadow fescue 1 to 4 pounds

Orchard grass 1 to 4 pounds

Red clover 6 pounds

Alsike clover 3 pounds

White clover 1 to 2 pounds

For poor lands it recommends this mixture:

Timothy 8 to 12 pounds

Red-top 4 pounds

Canadian blue-grass 4 pounds

Red clover 6 pounds

Alsike clover 3 pounds

White clover 1 pound

Zinn, of West Virginia, recommends the following mixture for permanent

pasture:

Timothy 4 pounds

Red-top 4 pounds

Orchard grass 4 pounds

Kentucky blue-grass 7 pounds

Red clover 2 pounds

Alsike clover 2 pounds

White clover 1 pound

Renewal of Permanent Pastures.--There is much pasture land that could

not be broken with profit for reseeding. There is neither time, nor

money, nor opportunity at the owner's hand for this purpose, and often

the loss of soil resulting from washing would be a bar if the labor

would cost nothing. The renewal of such grass lands can be made with

profit if pernicious weeds are not in the way. Plant-food, lime, and

grass seed are wanted. A disk or sharp spike-tooth harrow, used in

early spring or after an August rain, will give some fresh earth for

covering the seeds. A complete fertilizer always is needed. The clovers

should go into the seed-mixture used.

[Illustration: Sheep on a New York farm.]

Destroying Bushes.--The absence of sheep is evident in the appearance

of the greater area of permanent pasture in the mountainous regions of

the eastern states. Bushes, briers, and other weeds must be destroyed

if pasture land would be kept in a profitable state, and only the sheep

or the goat is the fully efficient aid of man in caring for such land.

The presence of dogs makes the tariff on wool, or lack of it, a minor

matter. The cost to the country, in indirect effect upon pastures only,

due to unrestrained dogs, is incalculable. The maintenance of good sods

without sheep is a problem without solution in some regions.

Close Grazing.--Much harm results from turning livestock on pastures

too early in the spring. The ground is kept soft by spring rains, and

the hoofs cut the turf. The grass needs its first leaves to enable it

to make rapid growth, and the first grass of spring is not nutritious.

Close grazing is harmful, exposing the soil to the sun and robbing it

of moisture. When winter comes, there should be sufficient grass to

serve as a mulch to the roots. It acts like a coat of manure, giving

new life to the plants the next spring. Good sods are not easily or

quickly made, and when they have been secured on land unfit for the

plow, their value measures the value of the land itself.

CHAPTER X

THE COWPEA

A Southern Legume.--The soils of the cold north are protected from

leaching during the winter by the action of frost. The plant-food is

locked up safely for another year when nature ceases her work of

production for the year. Farther south, in the center of the corn belt,

there are leaching periods in fall and spring and oftentimes during the

winter, but winter wheat thrives and, in ordinary crop-rotations,

covers much of the land that might otherwise lose plant-food. As we

pass from the northern to the southern states, the preservation of soil

fertility grows more difficult and at the same time the restoration of

humus becomes easier. The heat makes easy the change of organic matter

to soluble forms, and the rains cause waste, but the climate favors

plants that replace rapidly what is lost. In the work of supplying land

with fertility, directly and indirectly, the southern cowpea has an

important place. It is to the south what red clover is to the north,

and it overlaps part of the red-clover belt, having a rightful place as

far north as the Ohio Valley, and portions of Pennsylvania.

Characteristics.--The cowpea is closely related to the bean, and is

very unlike the Canada pea, which is a true pea, thriving only in a

cool climate. The cowpea has been grown in the southern states over one

hundred years, and the acreage is large, but it never has come into the

full use it deserves. Being a legume, it stores up nitrogen taken from

the air, and unlike red clover it makes its full growth within a short

period of time. It can grow on land too infertile for most kinds of

valuable plants, and on better land. The vines can crowd out nearly all

varieties of weeds. The roots go to a good depth and are thickly

covered with the nodules of nitrogen-gathering bacteria.

Varieties.--There are many varieties of the cowpea, and confusion of

names prevails, although some stations have done good service in

identification of individuals carrying a number of names. The very

quick-maturing varieties adapted to northern conditions do not make as

much foliage as the rank-growing ones that require a relatively long

season, but some of them are heavy producers of seed.

There are varieties requiring six months of southern heat to bring them

to maturity, and some failures attending the introduction of the cowpea

into more northern latitudes have been due to bad selection. A few

varieties reach maturity within two months of hot weather.

The trailing habit is affected by the soil, the bunch varieties tending

to trail when grown on fertile land. When the crop is wanted for seed,

the peas that do not trail heavily will prove more satisfactory. The

selection of variety is a matter of latitude and purpose, exactly as it

is with corn.

Fertilizing Value.--A heavy growth of the cowpea is worth as much to

the soil as a good crop of red clover. When the equivalent of two tons

of hay is produced, the roots and vines contain nearly as much

plant-food as the roots and first crop of medium red clover that makes

two tons of hay. Some analyses show a higher percentage of protein in

cowpea hay than in clover hay, and the experience of many stockmen

indicates that such is the case. The roots and stubble have somewhat

less fertilizing power than in the case of the clover, and all thin

soils should have the entire plant, or the manure from the hay, saved

without loss.

Comparison is made on the basis of equal adaptability of soil and

climate to clover and the cowpea. Going southward, the cowpea has the

advantage, and northward the clover gains. It is in the overlapping

belt that both should be freely used. The cowpea has distinct advantage

over the clover in its ability to supply nitrogen and organic matter

within a few months, and in its adaptation to very poor soils where

clover would not make much growth. As a catch crop it has great value.

Affecting Physical Condition.--The cowpea has marked influence upon the

physical condition of heavy soils, even when the vines are not plowed

down. This is due in some degree to the roots, and probably more to the

mulching effect of the vines during their growth. Heavy soils are made

much more mellow by the cowpea, and when the crop is removed for hay,

the stubble-land is easily prepared for a seeding to grass or small

grain. When the growth is plowed down, the soil may be made too loose

for seeding to small grain, but is put into prime condition for a

tilled crop.

Planting.--The land should be fitted as it is for corn. Light, sandy

soils require little preparation, and too often the seeding is made in

a woefully careless manner, the chief dependence being placed upon

sufficiently deep covering to insure germination. The ground should be

fitted as well as it is for a cash crop, being made fine and smooth. A

grain drill makes the seeding in a satisfactory manner, and the seed

may be drilled solid or in rows for cultivation. When the crop is grown

as a fertilizer or for hay, solid drilling is good, and about five

pecks of seed gives a good stand of plants if peas are sound. Much

cowpea seed is low in germination power, and the buyer should exercise

caution. When a seed crop is wanted, two to three pecks of seed per

acre, placed in drills 28 to 32 inches apart, make an excellent

seeding, as cultivation can be given. The amount of seed varies with

the variety. In northern latitudes a warm soil is to be desired, and

cultivation gives better results when a seeding to wheat will be made

on the pea-stubble.

There is evidence that the cowpea can make a heavy growth in soils too

deficient in lime for red clover, and it gained its first prominence in

southern Ohio on land that was failing to grow clover. It is the plant

of adversity as well as prosperity, adding rich organic matter to thin

soils, but making its full returns under better conditions. Lime

applications on acid soils give increase in yields. Its one absolute

requirement is heat, and in a cold summer its northern limit is

markedly depressed.

Inoculation.--The inoculation of the soil with cowpea bacteria is

necessary to best results in most regions new to the plant.

Self-inoculation is quicker in the cowpea than in alfalfa because the

vines carry some soil on them, and thus the dust in the seed crop may

be rich in bacteria. However, most new seedings of the cowpea do not

show a large number of nodules on the plant roots, and inoculation

pays. In some cases it makes the difference between failure and

success. Two hundred pounds of soil from an old field should be well

harrowed into each acre of land when preparing for a cowpea seeding in

a new region. The soils of the southern states contain the bacteria

just as the states in the clover belt are supplied with clover

bacteria.

Fertilizers.--The light soils of Maryland, New Jersey, and the southern

states are not naturally rich in phosphoric acid or potash. The cowpea

can draw its nitrogen from the air, but on all thin land it pays to use

200 to 300 pounds of acid phosphate and 50 pounds of muriate of potash

per acre for this crop which should have a luxuriant growth for the

soil's benefit. Such use of fertilizers is more profitable than their

use on the crop which follows.

Harvesting with Livestock.--When the cowpea is made into hay, there is

always danger that the most of the plant-food contained in it never

will get back to the soil on account of a careless handling of the

manure. The practice of pasturing with cows and hogs is excellent. The

feed is rich, and the manure is left on the ground. There is a saving

of labor.

If the full fertilizing value is wanted for the soil, the crop should

be plowed down. The trailing varieties form a tangled mass that cannot

be handled by an ordinary breaking-plow, but a stalk-cutter, run in the

direction the plow will follow, makes plowing possible. Pasturing with

cattle and hogs sufficiently to reduce the growth so that a plow can be

used is good practice.

The Cowpea for Hay.--The hay is one of our most palatable

feeding-stuffs. Livestock may reject it the first time it is put into

the manger, but a taste for it is quickly acquired, and soon it is

eaten greedily. The high content of protein makes it exceptionally

valuable for young animals and milk cows, and the manure contains a

high percentage of nitrogen. The difficulty in making the hay is a

drawback, but this is over-rated. While rain discolors the vines and

makes them unattractive in appearance, the hay remains more palatable

and nutritious than good timothy, if the leaves are not lost in curing.

When the first pods turn yellow, the crop should be harvested. The

vines can be left in the swath until the top leaves begin to burn and

then be put into windrows with a sulky hay-rake. The windrows should be

small, the rake merely serving to invert half the vines upon the other

half, bringing new surface to the sun. After another day of curing, the

windrows should be broken up into bunches no larger than can be pitched

upon the wagon by a workman, thus saving the trouble of disentangling

the vines. If rain comes, the bunches should be inverted the following

day. In dry, hot weather the curing proceeds rapidly, while in cooler

latitudes or cloudy weather the curing may require a week. The chief

point is to prevent undue exposure of the leaves to the sun, and this

is accomplished by the turning. The hay will mold in the mow if not

thoroughly well cured, unless placed in a large body in a deep, close

mow that excludes the air. Some farmers use the latter method

successfully, but the experimenter with the cowpea usually will fail,

and should prefer thorough field curing, at the risk of some damage

from rain and sun. The leaves are the most nutritious part of the

plant, excepting the seed.

As a Catch Crop.--A leading use of the cowpea is that of a catch crop,

either between other crops or in a growing crop, such as corn. Early

maturing varieties can be brought in between main crops of the rotation

in warm latitudes. The growth prevents the leaching of plant-food,

shades the ground, adds nitrogen to the soil, smothers weeds, and

produces material that is valuable as feed for livestock or an addition

of organic matter to the soil. When the time that can be devoted to the

crop is short, an early variety should be selected because its vines

are far more valuable to the soil than an equal volume of a

rank-growing variety that is not near maturity.

[Illustration: The cowpea seeded at the last cultivation of corn in the

Great Kanawha Valley, W. Va.]

If this legume were used whenever opportunity afforded along the

southern border of our northern states, and throughout the south, the

faded color of soils, resulting from leaching rains, would be replaced

by the darker colors that mark the presence of rich organic matter. It

is one of nature's best allies in the maintenance of soil fertility.

CHAPTER XI

OTHER LEGUMES AND CEREAL CATCH CROPS

The Soybean.--The soybean is gaining a place among the valuable legumes

of the United States, and the acreage is increasing as its merits

become known to all. Its northern limits of profitable production are

much farther north than those of the cowpea, and approach those of

corn. In the south it is gaining friends. Some of the advantages of the

soybean over the cowpea, as found by the Tennessee station, may be

stated as follows:

1. Greater seed production in case of fertile soils.

2. Less sensitiveness to cold in spring and fall.

3. Greater feeding value of the seed.

On the other hand, a stand of cowpea plants is surer in the case of

soils that crust, and germination runs higher. Its climbing habit makes

it better suited for growing with corn for forage. A less amount of

leaves is lost in curing.

Fertility Value.--There are so many varieties of the soybean and the

cowpea, and adaptation to soil and climate varies so widely, that a

fair comparison is difficult to make. In cool latitudes the soybean is

recognized as distinctly more profitable, making larger yields of vines

and of seed. Where adaptation is equal, the cowpea makes a slightly

larger growth of vines for hay, but the soybean gives a much richer lot

of seed for use as grain.

When soil fertility is the chief consideration, the adaptation of

climate and soil should decide our choice between these two legumes.

There is no serious difference where conditions for each are equally

good. In cool latitudes the soybean should be chosen. In the Ohio

Valley it is usually to be preferred. The greater part of the organic

matter and the plant-food is stored in the vines and seed.

Feeding Value.--The soybean makes a rich hay, surpassing clover, but it

is coarse, and its unattractive appearance has caused many farmers to

condemn it without trial. Livestock eat it greedily, and it is one of

our richest coarse feeds. The curing is more difficult than in the case

of the cowpea because the leaves drop early, and the plants must be

harvested before they approach maturity.

Probably the large yield of rich seed is the most important feature of

the soybean crop. A ton of the seed contains as much protein as a ton

of old-process oil meal, and three fourths as much as a ton of

cottonseed meal. A good crop of the soybean will yield 18 to 20 bushels

of seed, and as the nitrogen may be obtained chiefly from the air, the

protein from this crop will come to be a leading substitute for

purchased protein feeds.

Varieties.--There are many varieties of the soybean, and their

characteristics are modified by climatic conditions. Each region will

find the varieties best suited to its purposes by tests. When hay is

wanted, the variety should have fine stems and a leafy habit of growth.

It may not be a good producer of seed, or able to hold the seed

unshattered. The harvesting should be done when some lower leaves turn

brown and before the pods are half filled. This stage of maturity

should be reached early enough in the fall to insure some hot days for

making the hay, and to permit harvesting in time for seeding to wheat.

The preparation for wheat is made with the harrow and roller or plank

drag.

When the soybean is grown for seed, the variety should hold the peas

without undue shattering, and an erect grower is more easily handled

without loss of the crop. Varieties for regions will vary, as do

varieties of corn, according to climate.

The Planting.--Early varieties of the soybean in the south can be

planted as late as mid-summer, but farther north a profitable crop

requires nearly all of the summer heat. The planting may be made soon

after the usual time of planting corn, or whenever the ground has

become warm. The preparation of the soil should be more thorough than

that often given the cowpea. Solid drilling of five pecks of seed per

acre is satisfactory when the crop is for fertilizing purposes only,

and gives an excellent hay on land free of weeds. When the crop is

wanted for hay, however, wheat usually will follow, and it is much

better to plant in rows and to give two or three cultivations so that

the ground may be easily prepared for the wheat.

A seed crop should be grown in rows. Three pecks of seed in rows 28

inches apart is the usual amount.

The soybean does not come up through a crusted surface as well as most

other plants, and planting should not be made immediately before a

rain. The plants are tender and easily injured by use of a weeder.

The fertilizer requirement is like that of the cowpea. An application

of 200 pounds of acid phosphate per acre should be given, and the

addition of 50 pounds of muriate of potash often pays.

Harvesting.--The soybean is not an easy crop to handle without loss.

When grown for seed, the tendency of the pods to split and to drop the

seed compels early cutting, and that makes curing more difficult. The

mower is the only practical harvester on most farms, and the swath must

be turned out of the way of the horses to save tramping. A

side-delivery attachment can do the work. This is the best practice

when cut for hay. When used for mixing with corn in a silo, the

self-binder is satisfactory. The hay and seed crop must have thorough

field-curing in windrow and bunches, and the harvest comes in a season

when cold rains may prevail. This disadvantage of one of our most

valuable crops is to be taken into account, but it will not prevent

rapid increase in acreage as the merit of the soybean becomes known.

The Canada Pea.--Among field peas there are many varieties, but the one

chiefly grown in the United States under the general name of the Canada

pea is the Golden Vine. It makes a green forage or hay that is rich in

protein. Usually it is grown with oats, giving a hay nearly as

nutritious as that of clover. The crop is adapted to cold latitudes,

and the planting should be made as early in the spring as possible.

Fall-plowing of the land is to be advised on this account. A good

method of seeding is to drill in six pecks of the pea seed to a depth

of four inches, and then to drill in six pecks of oats.

The crop should be cut for hay when the oats are in the milk stage. At

this time the peas are forming pods. The hay is not easily made, but is

specially valuable for dairy cows.

There is no profitable place for the Canada pea in crop-rotations

farther south than the true oat-crop belt, except as a green-forage

crop. The soybean and red clover have greater usefulness in the center

of the corn belt.

Vetch.--A variety of vetch known as winter, sand, or hairy vetch is

coming into great usefulness as a catch crop. It is a winter annual,

and being a legume, it has special value as a fertilizing crop. It is

more hardy than crimson clover, and is grown as far north as winter

wheat. The seeding is made in August in the north, and when grown for

hay or seed, it needs rye or wheat to hold it up. Rye and vetch make a

rich and early green forage crop, and the proportion in which they are

seeded varies widely in practice. Six pecks of rye and 15 pounds of

vetch make an excellent seeding per acre.

When grown for seed, one to two pecks of rye and 20 to 30 pounds of

vetch may be used. The rye can be fairly well separated from the vetch

by use of a fanning-mill or an endless belt of felt so inclined that

the round vetch seed will roll down, while the rye sticks to the felt

and is carried over.

Vetch is excellent as a fertilizing crop, adding a great amount of

nitrogen to the soil when plowed down in May. If the seed were cheap,

its use would become much more common. Thirty pounds should be used

when seeding alone after summer crops or in corn. Farmers should

produce the seed for their farms, and use it freely. When sown for

seed, September first is a good date for the north. The seed matures in

June.

As vetch matures with wheat, it may easily become a weed on farms

devoted largely to small grain, but it is not to be feared where tilled

crops and sods are the chief consideration. Inoculation is needed for

best results, as in the case with other legumes new to a region.

Sweet Clover.--Much interest has been aroused within recent years in

sweet clover, a legume that formerly was regarded as a more or less

pernicious weed. Its friends regard it as a promising forage crop, but

too little is definitely known to permit its advocacy here except as a

soil-builder in the case of poor land that is not too deficient in lime

to permit good growth. Experiments have shown that a taste for this

bitter plant can be acquired by livestock, and it is nearly as

nutritious as alfalfa when cut before it becomes coarse and woody. It

is a strong grower, sending its roots well down into the subsoil, and

its great ability to secure nitrogen from the air enables it to make a

very heavy growth of top. The yield in forage usually exceeds that of

the clovers.

Its most peculiar characteristic is its ability to thrive in a poor,

compact soil that contains little humus. It may be seen in thrifty

condition on roadsides and in waste places that seemingly would not

support other plants. Laying aside all consideration of its

possibilities as a forage crop, it will come into greater popularity as

a soil-builder on thin land. It is found usually on land of limestone

formation, and shares with other legumes a liking for lime, but it has

been grown successfully in regions that are known to have a lime

deficiency.

There are two biennial varieties and one annual. The biennial having

white blossoms is the one most commonly seen, but the smaller variety

with yellow blossoms is more leafy and palatable. The larger variety is

the better fertilizer.

The seed does not germinate readily, and 20 to 30 pounds is used per

acre. The soil should be compact, and the seeding can be made in the

spring with a cover crop, or in August by itself. Inoculation is

necessary if the right bacteria are not present. Soil from an alfalfa

field will serve for inoculation.

An effort should be made to grow sweet clover on all infertile

hillsides that are lying bare. It stops washing and paves the way for a

sod of nutritious grasses.

Rye as a Cover Crop.--As has been stated elsewhere, the plant that

stores nitrogen in its organic matter is most desirable, but the

greater part of the soil's stock of humus did not come through legumes.

Among the good cover crops is rye, both on account of its ability to

grow under adverse conditions and because it produces a large amount of

material for the soil. When seeded in the early fall, its roots fill

the soil the following spring, and the tops furnish all the material

that can be plowed down with safety. In northern latitudes it is the

most dependable of all winter cover crops, making some growth in poorly

prepared seed-beds and on thin land. The most value is obtained from

early seedings, thus securing a good fall growth. Two bushels of seed

are sufficient in good ground seeded ten weeks before winter begins,

but two or three pecks should be added to this amount if the rye can be

given only a few weeks of growth before frost locks up the soil. Rye

can grow in warm spells of winter, and starts early in the spring. It

uses up some available fertility that might otherwise be lost, and

releases it when it rots in the ground.

When to plow Down.--If rye has made a good growth before spring, the

roots run deeper than the plow goes, and holds the soil much like a

grass sod. In such a case the plowing may be made early in the spring

without regard to the rye, though organic matter increases rapidly day

by day if the rye is permitted to grow. As a rule, it is safest to plow

down before the plants are eighteen inches high. They dry land out

rapidly, and any mass of matter in the bottom of the furrow interferes

with the rise of water from the subsoil. When the land is wanted for

oats or corn, a jointer should be used on the plow to insure burying

all the crop.

Buckwheat.--An excellent crop for green-manuring is buckwheat. It has

such unusual ability to grow in a poor soil that the farmer who makes

free use of it as a grain crop never boasts of acreage planted,

assuming that his land will not be highly regarded if known to be

devoted chiefly to buckwheat. It does not withstand heat well,

especially from period of blossoming to maturity, and therefore is

restricted to cool latitudes. When grown for grain, it usually is not

planted until July, and matures a crop in a shorter period than any

other grain. It is sensitive to frost, but may be planted as soon as

the ground is warm, and will give a good body of matter for plowing

down within eight weeks. The root growth is not extensive, but the crop

leaves naturally heavy soils more mellow, and it is an excellent

cleansing crop for weed-infested fields. It makes a less heavy growth

than rye, but can be used at a time of the year that rye would fail.

There is time in a single season to grow two crops of buckwheat for

green-manuring, turning the first crop down when the blossoms appear.

Oats.--When a fall growth is wanted for the soil, and it is preferred

that the plants be dead in the spring, oats make a good catch crop.

Thin land which is wanted for seeding to wheat and grass in the fall,

or for timothy and clover seeding in August, may use oats as a spring

cover crop. A large amount of humus-making material may be gained by

this means. The only danger lies in the effect upon soil moisture. The

oat crop uses up the water freely in its growth, and when permitted to

form heads before being plowed down, the mass of material in the bottom

of the furrow does not rot quickly enough to induce the rise of water

from the subsoil. The land should be plowed early enough to permit a

solid seed-bed to be made.

CHAPTER XII

STABLE MANURE

Livestock Farming.--The fertility of the soil is most safely guarded in

regions devoted to livestock farming. "Selling everything off the farm"

is a practice associated in the public mind with soil poverty. It is a

rule with few exceptions that the absence of livestock on the farm is

an index of gradual reduction in the productive power of the land.

Generally speaking, the farmers who feed the most of their crops on the

farm are maintaining fertility, and those who do not feed their crops

on the farm have been making drafts upon the soil's stores of available

plant-food that are evidenced in a reduction of yields. These

statements will have the assent of all careful observers. The inference

has been that the maintenance of fertility requires the return to the

land of all the manure that would result from feeding its crops on the

farm. We know that by such feeding we can return to the fields at least

four fifths of all the plant-food taken out by the crops, and we

loosely reason that such a scheme is demanded by nature. The

maintenance of fertility involves good arithmetic, and a plant must

have certain weights of mineral elements at command before it can grow,

but it is not true that the productive power of land is chiefly

dependent upon the return to it in manure of all the fertility removed

by its crops. If this were true, meat and other animal products would

be the sole food supply of the world's markets.

[Illustration: Texas calves on an Ohio farm.]

The Place for Cattle.--There are general trends in human practice that

cannot be changed by man. A change in human diet that makes the

percentage of meat lower will not come through propaganda, but there

are forces at work that will restrict the consumption of meat by the

individual. The increase in population makes heavier demand for food.

Armsby has shown that the fattening steer returns to man for food only

3 per cent of the energy value of the corn consumed by it, and in

pork-production this percentage scarcely rises to 16. This is the

reason meat-making animals give way before increase in population in

congested countries. Their office becomes, more and more, the

conversion of products inedible to man to edible products. In our

country their number will increase, doubtless, for a long period of

time, finding their places more surely on eastern farms rather than on

western ranches. They must find the cheaper land, and that is no longer

confined to the west. They must be where coarse materials, inedible to

man, are found, and that is on eastern as well as on western farms.

Their office will not be the conversion of crops into manure, but the

conversion of coarse materials into human food in the form of meat or

milk. This is the trend, and while the consummation may happily be far

in the future, its consideration helps us to an appreciation of the

facts regarding nature's provision for maintaining the productiveness

of the soil.

Sales off the Farm.--The day is now here when the major portion of

human food must be provided in grain and vegetables and fruit, and the

demand for hay and grain for animals off the farm is very large. Fiber

products likewise must be supplied. The draft upon the soil is heavy,

but it must be good farm practice to supply bread and vegetables and

fruit to the 70 per cent of our population that is not on farms. The

great majority of farmers do not feed all their crops to livestock, and

the amount of food-stuffs, for human beings and animals, that is now

going off the farms is none too great.

Many farmers who incline to believe that they are safely guarding

fertility by feeding the most of their crops are not returning to the

fields one third of the plant-food that their crops remove. There is no

virtue in feeding when the manure is permitted to waste away. The

losses in stable and barnyard, the wastes from bad distribution by

animals, and the sales from the farm of some crops, animals, and milk,

lead to the estimate that one half of the farms on which livestock is

kept do not give to the fields in the form of manure over 30 per cent

of the fertility taken out of them by crops. This estimate, for which

no accurate data is possible, probably is too high. The sales of food

for man and animal are a necessity, and the scheme of farming involving

such sales is right, provided the farmer makes use of other supplies of

fertility. The area devoted to such sales will grow greater because

human needs are imperative. Livestock will become more and more a means

of working over the material that man cannot eat--the grass, hay,

stalks, by-products in manufacture, and coarse grains. The demand for

meat and milk will lead to careful conversion of material into this

form of food, and the animals on eastern farms will increase in number

for a time, while sales of grain and vegetables grow greater. The draft

upon soil fertility through sales must increase because every pound of

material sold from the farm carries plant-food in it.

The Value of Manure.--It is not possible to put a commercial valuation

upon farm manures that may be a sure guide to any farmer. The value

depends upon what the individual can get out of it in crops and

improved soil conditions. It is rather idle to say that the annual

product of a horse in the form of manure is $30, or more or less, even

when an analysis shows that the nitrogen, phosphoric acid, and potash

contained in it are worth that sum when valued at the market prices of

those plant constituents. If the total amount of fertility found in the

voidings of all the animals of the farm were provided in a pile of

commercial fertilizer containing the same amount of each plant

constituent, its worth to the farmer would depend upon his ability to

convert all that fertility into crops at a profit. There are farmers so

situated in respect to soils, crops, and markets that they can make a

good profit from an investment of $30 in the total liquid and solid

voidings of a horse for a year. On the other hand, there are many who

would fail. The values usually given are relative and suggestive. They

are aids in forming judgment. Actual value on the farm depends much on

the man.

The Content of Manure.--When the crops of a farm are fed, the manure

contains nearly all the plant-food that went originally into the crops.

In the case of idle work-horses on a maintenance ration, the manure

contains practically all the plant-food. Cows giving milk remove some

fertility, and a growing calf or colt may take out 30 per cent. There

is some waste beyond control, but when manure is made on tight floors

with good bedding, and is drawn to the field fast as made, on the

average it carries back to the soil fully four fifths of the plant-food

that existed in the feed. Disregarding all cash valuations for the

moment, here is an index of value that should be sufficient in itself

to encourage the feeding of crops on the farm and the careful saving of

the manure. When one can market his crops to animals on the farm at

their cash value, and at the same time retain for his fields four

fifths of all the fertility, he is like a manufacturer who can use much

of his raw material over and over again. The value is in the manure,

and full appreciation is lacking only because a majority of farms do

not provide for careful saving of its valuable constituents.

Relative Values.--The plant-food content of manure is determined

chiefly by the feed. The animals add nothing: they subtract. The kind

of animals consuming the feed does not affect materially the value of

the manure made from it, if the animals are mature and not giving milk.

The manures from the various kinds of animals differ in value per ton

because the feeds differ in character and the manure varies in

percentage of water. On an average, however, the total annual product

of manure from farm animals, per 1000 pounds of live weight, does not

vary widely in value. The rich protein feeds given the cow, and the

heavy feeding, more than make amends for the fertility that goes into

the milk, and her annual product, per 1000 pounds of live weight, may

exceed in value that of the horse by 25 per cent. This is likewise true

of the pig, figured on the 1000-pound basis, while in the case of the

sheep the value, per 1000 pounds of live weight, is near that of the

horse.

[Illustration: In the fertile Miami Valley, Ohio.]

These variations are not wide enough to have great importance to the

livestock farmer. The manure represents to him four fifths of all the

fertility that was contained by the feed he gave the various animals.

They added no plant-food, and they took away only a fraction that was

not large. They converted the crops into a form of plant-food that

either is available or can become so quickly enough, and in addition to

the nitrogen, phosphoric acid, and potash that would have a high

valuation in a commercial fertilizer, there is a body of organic matter

that affects the physical condition of the soil favorably. The manure

also promotes the multiplication of friendly soil bacteria. Its

possibilities are so great that the inference of many farmers that no

successful agriculture can be maintained without it is very natural.

Amount of Manure.--Vivian states that the amount of manure that may be

made from feed can be determined by multiplying the total weight of dry

matter in the feed by 3. This assumes that bedding will be used in

sufficient amount to absorb the urine, and that will require material

containing one fourth as much dry matter as there is in the feed. When

the amount of hay and grain is known, and the dry matter in all

succulent feed is estimated, the total product of manure in tons can be

arrived at with fair accuracy.

Analysis of Manure.--As has been stated, the content of the manure must

depend chiefly upon the character of the feed. We are accustomed to

combine feeding stuffs in differing proportions for horses, cows, pigs,

and sheep. Van Slyke names the following approximate percentages of

plant-food constituents in fresh excrements of farm animals, the solid

and liquid being mixed:

+----------+----------+------------+----------+

+----------+----------+------------+----------+

| Horse | 0.70 | 0.25 | 0.55 |

| Cow | 0.60 | 0.15 | 0.45 |

| Pig | 0.50 | 0.35 | 0.40 |

| Sheep | 0.95 | 0.35 | 1.00 |

| Hen | 1.00 | 0.80 | 0.40 |

+----------+----------+------------+----------+

He estimates that one ton of average mixed stable manure, inclusive of

absorbents, contains approximately 10 pounds of nitrogen, 5 pounds of

phosphoric acid, and 10 pounds of potash.

CHAPTER XIII

CARE OF STABLE MANURE

Common Source of Losses.--When we bear in mind that four fifths of all

the fertility removed from the land in the grains and coarse stuffs fed

on the farm may be recovered from the animals and returned to the soil,

we can appreciate the consideration that the care of manure should have

on every farm. The careless methods that prevail in most sections of

the country are an inheritance from the day when soils were new and

full of fertility. These methods continue partly through a lack of

confidence in the statements that the liquid portion of animal

excrements, in average mixed stable manure, has nearly as great value

as the solid portion. If this fact were accepted, many of the losses

would be stopped. Another reason for continuance of careless methods is

failure to appreciate that the soluble portion of manure is the highly

valuable part, and that leaching in the barnyard carries away value

more rapidly than decrease in volume of manure indicates. The widely

demonstrated facts do not have effective acceptance, and enormous loss

continues.

Thorne found that manure placed in flat piles in the barnyard in

January, and allowed to lie until April, lost one third of its value.

Under the conditions prevailing on many farms the loss suffered by

exposure of manure is far greater.

[Illustration: Concrete stable floors.]

Caring for Liquid Manure.--If all manure were in solids, one great

difficulty in caring for it would not exist. The nitrogen is the most

valuable element in manure, and two fifths of all of it in horse manure

is found in the liquid. In the case of cow manure, over one half of the

nitrogen is found in the liquid. More than this, a pound of nitrogen in

the liquid has greater value than a pound in the solid because of its

nearly immediate availability. There is only one good way of caring for

the liquids, and that is by use of absorbents on tight floors or in

tight gutters. American farmers find cisterns and similar devices

nuisances. The first consideration is to make the floor water-tight,

and clay will not do this. The virtues of puddled clay have had many

advocates, but examination of clay floors after use will show that

valuable constituents of the manure have been escaping. The soils of

the country cannot afford the loss, and careful farm management

requires acceptance of the truth that a tight floor is as necessary to

the stable as to the granary. The difficulty in supplying a sufficient

amount of absorbents on tight floors only emphasizes the loss where

floors are not water-tight.

Use of Preservatives.--The use of land-plaster in stables helps to

prevent loss of the nitrogen-content through fermentation. Its value

does not lie chiefly in physical action as an absorbent, but the

beneficial results come through chemical action. The volatile part of

the manure is changed into a more stable form. In recent years this

preservative has fallen somewhat into disuse, as acid phosphate

contains like material and also supplies phosphoric acid to the manure.

The phosphoric acid content of stable manure is too low for all soils,

and the reenforcement by means of acid phosphate would be good practice

even if there were no preservative effect. The use of fifty pounds of

acid phosphate to each ton of manure will assist materially in

preserving the nitrogen, and the gain in phosphoric acid will repay all

the cost. It should be used daily on the moist manure, as made in the

stable, and preferably just before bedding is added, so that the

phosphate will not come into direct contact with the feet of the

animals. Some stockmen prefer the use of acid phosphate and kainit

mixed half-and-half. The latter is a carrier of potash, and is a

preservative of nitrogen.

The use of ground rock-phosphate in stables is coming into use in some

localities, chiefly through the recommendation that it be mixed with

manure to secure availability of its own plant-food. It is not a

preservative except in so far as it acts physically as an absorbent. It

should not displace acid phosphate in stables, the preservation of

nitrogen in the manure being the vital matter.

Spreading as Made.--When farm conditions make it feasible to draw and

spread manure fast as made, the danger of heavy loss in storing is

escaped. There is evidence that no appreciable escape of fertility

occurs when manure is spread on land that is not covered with ice. The

phosphoric acid and potash are minerals, and leach into the soil. The

nitrogen does not change into a gas in any appreciable amount when

spread over the surface, and it likewise leaches into the soil. There

are soils in which the decay of the organic matter would have a more

beneficial effect than the rotting upon the surface, it may be, but the

mulching effect of the manure is valuable. There should be no doubt

that the loss from manure is kept to a minimum when it goes directly to

the soil. In some latitudes the snow and ice oftentimes prevent

spreading, or make it inadvisable, and in many farm schemes it is

desirable to hold manure for special fields and crops. Some means of

storing manure must be provided in these instances.

The Covered Yard.--If the possible value of manure were realized,

provision for its care would be made as promptly and surely as

provision for the care of a harvested crop. There are only three

conditions that must be provided in order that manure may be preserved

without much loss. The manure must be protected from leaching rains, it

must be kept moist, and air must be excluded. The exposure of stable

manure to the processes of fermentation and leaching, produces a waste

that is believed to amount to several hundreds of millions of dollars

in the United States annually. The day will come when no farmer will be

willing to share heavily in a loss from this source, but will either

spread manure fast as made or provide a roof for the stored manure. An

absolutely tight floor is not so great a necessity as it is in the

stable, because the amount of moisture is under control, but many

farmers prefer to make concrete floors for the manure-shed and thus to

guard against any loss from leaching. The chief cost may be confined to

the roof.

A better plan is to inclose three sides, making them so tight that all

drafts will be prevented, and to use the shed as a place of exercise

for cows or other livestock. We have learned within recent years that

such an inclosure is more healthful and comfortable for cattle than

stalls in an inclosed building, no matter how cold the weather may be.

The fresh air without any drafts, and the liberty of movement, are

needed. This shed should be connected with the stable, and on its floor

the manure from the stables may be spread daily. It should be scattered

evenly over the surface, and the mass can be kept firm by the tramping

of the animals. It may be necessary to add some water at intervals to

keep the mass sufficiently moist. The water excludes air and assists in

holding harmful fermentation in check.

Harmless Fermentation.--There is a kind of fermentation in manure that

goes on in the absence of air. It is due to bacteria that break up the

organic matter, producing rotted manure. This is not attended by much

loss, and proceeds beneath the surface of the moist and packed mass.

Manure properly controlled under a roof goes into prime condition for

spreading later in the season. The only danger is neglect, and

especially when the livestock is removed to the pasture fields in the

spring. If no water is added from time to time, hot fermentation

replaces the harmless kind because air can penetrate through the bed of

manure. Compactness and moisture can save the plant-food with small

loss throughout the summer, and a body of good manure is available when

needed for top-dressing land in the summer.

Rotted Manure.--Mixed stable manure contains in a ton as many pounds of

potash as it does of nitrogen, and yet we speak of it as a highly

nitrogenous fertilizer. When fresh manure has suffered no loss of the

liquid part, much of its nitrogen is almost immediately available. The

nitrogen in the urine is in soluble forms, and fermentation quickly

occurs. When manure is used on grass, it cannot be too fresh, as the

immediate action of the nitrogen is desirable. Vegetable growers often

prefer a slower and more continuous action, and the rotting of manure

under right conditions changes the liquid nitrogen into compounds that

act more slowly.

The solid material in horse manure contains less water than that of the

cow, and this absence of water permits quick fermentation when air is

present. The use of large quantities of such manure per acre is not

liked by vegetable-growers. Rotting under control in a covered barnyard

has a beneficial effect for this reason when a hot manure is not

wanted. The covered shed costs some money, and there is a loss

estimated at 10 per cent under the best conditions, but when manure

cannot be drawn fast as made, there is compensation in improved

condition for certain soils and crops.

Composts.--The compost, involving the handling of manure and soil, has

no rightful place on the average farm. The gardener or trucker using

great quantities of manure per acre must let some of the fermentation

occur before he incorporates it with the soil, or harm will result. He

wants reduction in volume, and such change in character that it will

add to the retentive character of the soil respecting moisture instead

of drying the soil out. He can afford all the labor of piling the

manure with layers of sods or other material, and the turning to secure

mixing. It is his business to watch it so that loss will not occur.

The farmer uses manure in smaller quantities per acre. Probably all his

fields need the full action of the organic matter in its rotting. The

percentage of humus-making material is low. The place for fresh manure

is on the land, when this is feasible. The covered shed is a device for

holding manure with least possible loss when spreading cannot be done,

or a supply must be carried over for land in the summer. The gain in

condition is only incidental, and an advantage chiefly to vegetables.

The composting of manure by gardeners is not a practice to be copied on

most farms.

Poultry Manure.--The value of poultry manure often is overestimated.

Its content of plant-food is one half greater than that of horse

manure, ton for ton. The availability of the nitrogen is so great that

returns from applications are immediate, and give the impression of

greater strength than is possessed. Its availability makes it excellent

for plants that need forcing. For such use it needs reenforcing only

with acid phosphate, but as a general manure it should have the

addition of potash. Acid phosphate should be used in the poultry-house

to prevent loss of nitrogen, which escapes quickly on account of rapid

fermentation, and to supply phosphoric acid. Thirty pounds of acid

phosphate to each 100 pounds of the manure gives a mixture containing

one pound of nitrogen, three pounds of phosphoric acid, and two fifths

of a pound of potash. The addition of four pounds of muriate of potash

makes the mixture a well-balanced and effective fertilizer when used at

the rate of 500 to 1000 pounds per acre. Dry muck or loam should be

mixed with it to serve as an absorbent and to give good physical

condition.

CHAPTER XIV

THE USE OF STABLE MANURE

Controlling Factors.--The farm supply of stable manure is a carrier of

plant-food, returning to the soil four fifths of all the fertility

removed in the crops fed, but it is much more than this. Land which

receives only plant-food, as may be the case when fertility is supplied

in commercial fertilizers, loses good physical condition. Organic

matter is needed for maintenance of physical condition, the retention

of soil moisture, the freeing of inert minerals in the land, and the

promotion of bacterial life in the soil. No small share of the value of

a ton of manure is due to its organic matter. This is a factor in the

problem when deciding what disposition of the manure will pay best. One

field may be in condition to respond fully to the use of commercial

fertilizers, while another is too deficient in humus for best results.

Some crops are more insistent upon supplies of organic matter than

others.

Again, the disposition of the manure depends upon the supply. If most

crops are fed on the farm, the manure is a leading source of fertility

for all fields and crops, and may be used once or twice in the

crop-rotation on every field. If the manure is in small amount, due to

a scheme of farming involving the growing of crops for market, the

function of the manure may be only to encourage the starting of sods,

in which legumes are a leading factor.

Direct Use for Corn.--The practice of spreading manure on grass land

for corn is based upon much good experience. The custom is nearly

universal in regions where corn is an important part of a four, five,

or six years' rotation, and all of the corn and hay is fed on the farm.

This disposition of the manure permits the handling at times when other

work does not rush. The supply carried over from the spring is put on

in late summer, and the manure made in the early part of the winter can

be drawn to the field fast as made. Manure spread immediately before

the sod is broken is less effective, as no leaching of soluble elements

into the surface soil occurs before the coarse material is buried in

the bottom of the furrow.

[Illustration: Corn in the Ohio Valley.]

The use of fresh manures for corn is rational, because corn is a gross

feeder and requires much nitrogen. All plants having heavy foliage can

use nitrogen in large amounts. It is possible to apply manure in

excessive amount for this cereal, the growth of stalk becoming out of

proportion to the ear, but the instances are relatively few. Ordinarily

corn suffers from lack of nitrogen. When the farm manure is in large

amount, its direct use for corn is good practice.

Effect upon Moisture.--Coarse manures should not be plowed down late in

the spring, as they increase the ill effects of drouth. Decayed

vegetation, well mixed with the soil, increases the soil's

water-holding capacity, but undecayed material in the bottom of the

furrow is harmful. Fresh, strawy manure, made immediately before the

time for breaking a sod, is preferably carried over in a covered shed

until a later season of the year.

When manure has been spread upon a sod in the fall or early winter, it

decays quickly after the plowing, and aids in resistance to drouth.

When it is plowed down, the ground is kept more porous, and the

presence of plant-food and moisture at or near the depth of plowing

encourages deeper rooting of plants, and thus indirectly assists them

to withstand dry weather. If the plowing is good in character, leaving

the furrow-slice partly on edge, and permitting the harrow to mix part

of the turf and the manure with the remainder of the soil, the best

conditions respecting moisture are secured.

Manure on Grass.--When the crop-rotation embraces two or more years of

grass, or one of clover followed by only one of grass, it is better

practice to use the manure to thicken the sod. The object in view is

the largest possible amount of crops, and the maximum amount of organic

matter for the soil. Grass is a heavy feeder, like corn, and makes good

use of nitrogen. Its roots fill the soil so that no loss attends the

use of manure. When the supply is given the grass, after the harvest of

the second crop of clover and during the winter, the timothy can make a

rank growth. The part of the plant above ground has corresponding

development below ground. Not only does a large increase in the hay

crop result, but the heavy mass of grass roots, the aftermath, and the

remains of the manure provide a great amount of fertility for the corn

which follows. The increase in hay permits a corresponding increase in

the manure supply the next year, if it is fed, and if it is sold on

account of a market price greater than its value for feed and manure,

it adds to income materially--and that is one reason for farming.

Manure on Potatoes.--There are excellent cash crops that may get more

than their fair share of the farm supply of fertility, and against the

interest of fields in the farm not adapted to cash crops. The

justification is found in the farm ledger. In some regions potatoes are

the best crop in point of net income per acre, where the acreage is

kept restricted so that there may be plenty of organic matter to help

in conserving moisture. It is not good practice to use fresh manure,

and especially that from horse-stables, for potatoes. A heavy

application makes an excessive growth of vine, and the yield of tubers

suffers. A stronger deterrent is the effect that fresh manure has on

the development of the spores that produce the disease known as

potato-scab. Rotted manure is less dangerous, and few crops repay its

use in higher degree than the potato. Some growers prefer to make heavy

application of fresh manure to grass for corn, and follow with potatoes

so that they can profit by the rotted organic matter that remains. In

this way the physical condition is made excellent, moisture is well

held in a dry season, and commercial fertilizers can supplement the

plant-food left in the manure.

When to plow Down.--Excellent farmers differ regarding the relative

efficiencies of manure plowed down and that mixed with the top soil.

Both classes may be right for their individual instances. The plowing

down of manure helps to deepen the soil, and that always is desirable.

It causes plants to root deeply, and that is a distinct benefit in a

drouthy season, and always desirable. When a soil is in such tilth that

the breaking-plow always brings fertile soil to the surface, the

plowing down of manure gives excellent results, though it should be

permitted to leach at the surface for a few weeks before being turned

under. When land is being prepared for a seeding to grass or clover,

the supply of manure should not be plowed down wherever the

breaking-plow brings soil to the surface that is deficient in humus. In

the latter case the manure always should be used as a top-dressing, and

should be evenly spread and well mixed with the surface soil. It is

needed there far more than it can be needed farther down. The surface

soil always should have a high content of organic matter.

Heavy Applications.--When the farm supply of manure is small,

applications should be light. The manure should not be the dependence

for plant-food on a part of a field, or a single field of the farm,

under such circumstances. It is more profitable to give a light

dressing to a larger area. The manure is needed to make a fertilizing

crop grow, and a very few tons per acre can assist greatly, when

rightly used. The manure is needed to furnish bacteria to the soil, and

a small amount per acre is useful for this purpose. Always there is

temptation to use all the manure on a field convenient to the barn, and

to concentrate it on a sufficiently small area to make a good yield

sure. The loss to the farm in this method is heavy. The thin spots and

the thin fields have first right to the manure as a top-dressing, and

six tons per acre will bring larger returns per ton than twelve tons

per acre. At the Pennsylvania experiment station the land receiving ten

tons of manure per acre in the common four years' rotation of corn,

oats, wheat, and mixed clover and grass gives added returns of $1.63 a

ton, while an application of eight tons pays $1.85 a ton, and a six-ton

application brings the value per ton up to $2.41. These applications

are made twice in the four years.

Reenforcement with Minerals.--A ton of mixed manure in the stable

contains about ten pounds of nitrogen, five pounds of phosphoric acid,

and ten pounds of potash. This makes the percentage of nitrogen and

potash the same, while the percentage of phosphoric acid is only half

as high. A commercial fertilizer of such percentages would be esteemed

a badly balanced one. Certainly the phosphoric acid should be

relatively high, as this constituent of plant-food runs low in the

soil. If 50 pounds of 14 per cent acid phosphate were added to each ton

of manure while it is being made in the stable, seven pounds of

phosphoric acid would be added, making the percentage in the manure a

little higher than that of the nitrogen and the potash. A better

balance is given to the fertility. There cannot be any loss in this

purchased plant-food, if the stable floor is tight. Fermentation cannot

drive it off, and when applied to the soil it is tightly held.

Practically no phosphoric acid is found in drainage waters. Eight tons

of manure thus reenforced would contain the same amount of plant-food

as a ton of fertilizer having 4 per cent nitrogen, 5 per cent

phosphoric acid, and 4 per cent potash. The addition of the 50 pounds

of acid phosphate per ton does not bring the phosphoric acid content up

as high relatively as in most commercial fertilizers, but it helps. The

total amount in the eight tons manure may be sufficient, and the

greater part of the total has sufficiently immediate availability,

while the manure must undergo decomposition, and some of the nitrogen

and potash does not become available within the year.

Durability of Manure.--Tests of the durability of manure in the soil

involve some uncertain factors, but we are interested only in the

effects of applications. These effects may continue for a long term of

years, and an example will illustrate. Land may be too infertile to

make a good clover sod. If a good dressing of manure be given half the

land, affording proper conditions for making a sod, the result will be

a heavy growth of clover, while the seeding on the unmanured half will

be nearly a failure. If no manure or fertilizer be used in the

crop-rotation, the probability is the manured portion of the field will

again make a fairly good sod. How much this success may be due to the

remains of the manure, and how much is attributable to the effect of

the clover and to better bacterial life introduced and favored by the

manure, no one knows. Probably the greater part of the benefit comes

only indirectly from the manure applied three or four years previously.

Half of the field may thus be lifted out of a helpless state and remain

out of it for a long term of years, while the other half grows only

poorer. A probable illustration of this lasting indirect effect may be

seen in one of the plats in the soil fertility experiments on the

Pennsylvania experiment station farm.

Experiments at the Rothamstead station, England, show some lasting

results from applications of manure. Director Hall cites the case of

one plat of grass land which was highly manured each year from 1856 to

1863, and has since been left unmanured. In 1864 this plat gave double

the yield of an adjoining plat which had been left unmanured during the

eight years. In 1865 the plat, last manured in 1863, gave over double

the yield of the unmanured. In the following ten years its yield was a

half more than that of the unmanured. In the next ten years the yield

was a quarter more. In the next ten years it fell to 6 per cent more

than the plat that had received no manure in the beginning of the

experiment. In the following ten years it rose to 15 per cent. Here is

a lasting effect of manure for over forty years where grass was grown

continuously.

CHAPTER XV

CROP-ROTATIONS

The Farm Scheme.--Notwithstanding some of the theorizing that does not

commend itself to the practical man, farm management is taking on the

form of a science. It involves the organization of a farm for best

results, and in the scheme that should be worked out for any particular

farm the most important feature is the crop-rotation. The selection of

crops is controlled by so many local considerations, including the

personal likes and dislikes of the farmer, that very rightly the kinds

of rotation are innumerable. The order in which crops may be grown with

most profit is less variable, and yet even here local conditions may

quickly derange the scheme of a theorist. There is, however, such right

relation of facts to each other that we are getting a working

philosophy, and the individual farmer can bend practice to his own

liking in considerable degree, and yet not compel plants to do their

part at a disadvantage. He has much liberty in the order of their

growing, without endangering profits materially. Theoretically, this is

not true, and the factors of production on any farm are such that the

largest return is obtainable in only one scheme of farming. Practically

there is rather wide liberty.

Value of Rotation.--Experience has shown the benefit of variety in

crops grown on land. Among the advantages of crop-rotation are the

following:

1. It enables the farmer to maintain the supply of organic matter

in his soil. The roots and stubble of a grain crop are insufficient

for this purpose, and the introduction of a sod or cover crop is

helpful.

2. It permits the use of legumes to secure cheap supplies of

nitrogen.

3. Some plants feed near the surface of the ground, and the use of

other plants which send roots deeper adds to the production.

4. Some crops leave the soil in bad physical condition, and the use

of other crops in the rotation serves as a corrective.

5. The keeping of livestock is made more feasible and profitable,

and this leads to increase in farm manures.

6. In a proper succession of crops the soil is covered with living

plants nearly all the time, and thus is prevented from washing or

leaching.

7. In addition to these influences upon soil fertility, crop-rotation

assists in control of insect and fungous foes and of weeds; it

permits such distribution of labor on the farm that the largest

total production may be secured by its employment; and it saves the

farmer from sole dependence upon a single crop.

[Illustration: Penn's Valley, Pennsylvania.]

Selection of Crops.--The natural inclination of the farmer is a

consideration that cannot be ignored. If a man does not like certain

kinds of animals or crops, his farm or market must possess an unusual

advantage to counter-balance. Illustration of this truth may be seen in

every farming community.

As a rule, the crops should be those that are well adapted to the

particular soils upon which they are grown. It is up-hill work to

compete with producers whose soils have far better adaptation, unless

the local markets equalize conditions.

The crops should follow each other in such succession that each crop

naturally paves the way for the next one in the succession, or at least

does not place its successor at a disadvantage.

When it is feasible, a rather large proportion of the entire produce of

the rotation should be feeding-stuff for livestock, as soil fertility

is most easily guarded by livestock farming. This is desirable when

consistent with profit, but, as we have seen, it is not an absolute

essential.

An Old Succession of Crops.--In the corn belt of the northern states

some time-honored crop-rotations have been formed by corn, oats, wheat,

clover, and timothy. The number of years devoted to the grain and to

the sod has varied with the soil and the desire of its owner. A common

succession is corn one year, oats one year, wheat one year, clover and

timothy one year, timothy one year--a five years' rotation that has

much substantial success behind it. Such a rotation is wholly

reasonable and in accord with the nature of things. Every year

furnishes some organic matter for the soil in roots and stubble, and

all the produce of four years out of the five may be fed on the farm.

There is one cash crop, or two if the price of the clear timothy hay

justifies sale.

The manure may be hauled upon the sod when other work does not press,

and it goes where the crop is one that prefers fresh manure, be that

the grass or the corn. There is plenty of time after the corn to

prepare for oats, and after the oats to prepare for wheat. The

preparation for the wheat is sufficient for the clover and timothy. The

seedings come only in the spring and the fall, when rainfall is more

abundant and effective than in mid-summer. The danger of failure in

case of this rotation is relatively small.

Corn Two Years.--Hunt says that the prosperity of the east, as a whole,

would be greatly increased if the rotations of crops were so modified

as to increase the corn acreage. He suggests the four rotations given

in the table below, which is taken from Bulletin 116 of the

Pennsylvania experiment station. The fertilizers recommended should

maintain fertility.

CORN IN CROP-ROTATIONS

+-------+-------+-------+-------+-------------------------------------+

| 3 Yr. | 4 Yr. | 5 Yr. | 7 Yr. | |

| ------+-------+-------+-------+-------------------------------------+

| | | | 1 | Corn: 6 to 10 loads of manure and 25|

| 1 | 1 | 1 | 2 | Corn: 6 to 10 loads of manure and 25|

| | 2 | 2 | 3 | Oats: no fertilizer. |

| 2 | 3 | 3 | 4 | Wheat: 50 pounds each of phosphoric |

| 3 | 4 | 4 | 5 | Clover and timothy: no fertilizer. |

| | | 5 | 6 | Timothy: 25 pounds each of nitrogen,|

| | | | 7 | Timothy: 25 pounds each of nitrogen,|

+-------+-------+-------+-------+-------------------------------------+

The Oat Crop.--In the northern part of the corn belt the oat crop is

profitable. In the southern half of Ohio and regions of like temperature

the oat crop rarely pays. The heat, when the oat is in the milk stage,

usually is too great. The tendency there is to eliminate this crop.

Where silage is wanted, the stubble-land can be seeded directly to

wheat with good results. A common practice is to seed to wheat between

the shocked corn, and the wheat does poorly unless the soil is quite

fertile.

Two Crops of Wheat.--A common practice has been to grow two crops of

wheat, seeding first in the corn stubble-land, and plowing the ground

for the second wheat crop, making a smooth surface for mowing. This

method ceased to pay well when wheat became low in price. It has the

advantage of giving two cash crops to the rotation.

Where winter wheat does not thrive in the north, it is dropped out, and

the seeding to clover and grass is with the oat crop. There is the

compensation of a large oat yield where the climate is too cold for a

good crop of wheat.

[Illustration: In the Shenandoah Valley.]

The Clover and Timothy.--The timothy and clover sod is made

inexpensively so far as labor is concerned. The first crop of hay is

chiefly clover, and the soil is enriched by the roots and stubble,

while the hay is converted into manure.

The second year the hay is nearly clear timothy. The sod should not be

left until it becomes thin, but should be turned under while heavy, no

matter if this must be after one season's harvest, or two. A sod stands

three or four years for harvest on some farms, and without heavy

fertilization there is decrease in fertility.

Two Legumes in the Rotation.--If all the crops of this five years'

rotation, excepting wheat, were fed on the farm, and if all the manure

were saved and rightly applied, there would be little or no difficulty

in maintaining fertility, provided the soil were friendly to clover.

The fact is that much such land has grown poorer, and it is known that

another legume is needed in the rotation. The substitution of the

soybean or cowpea for the oat crop gives excellent results. It makes a

large supply of rich hay, and it fits the soil nicely for winter grain.

The use of the breaking-plow is escaped. The surface of the land is in

good tilth, especially if the legume was planted in rows so that

cultivation could be given. A cutaway harrow, run shallow, and a roller

make the seed-bed. Near the southern edge of the oat belt this

substitution gives more value in the crop following corn, and at the

same time conserves soil fertility.

Where land is thin, a four years' rotation of corn, soybeans or

cowpeas, wheat, and clover is one of the best, because it contains two

leguminous crops, and because one of them favors the wheat which

follows and the clover seeded in the wheat.

Potatoes after Corn.--When potatoes are grown in the corn belt, a five

years' rotation of corn, potatoes, oats, wheat, and clover, or corn,

potatoes, wheat, clover, and timothy, is one of the best. When a late

potato crop is grown, there is not time for seeding to wheat in cool

latitudes, and the oat crop, or the soybean, fits in best. Farther

south, where the oat crop is less profitable, there usually is time to

go directly to wheat.

The advantage in this rotation is that the fresh manure can be used on

the sod for the corn, and the potato thrives in the rotted remains of

the sod and manure. Corn leaves the soil in good physical condition for

the potato. Commercial fertilizer is used freely for the potato, which

repays fertilization in higher degree than most other staple crops. The

land can be prepared for seeding to wheat and grass with a minimum

amount of labor. The rotation is excellent where there is enough

fertility for the potato, which usually can be by far the most

profitable crop in the entire rotation.

A Three Years' Rotation.--Farm conditions may require that certain

fields in the farm go under a crop-rotation covering three years. In

the winter wheat belt this may be clover, corn, and wheat, or clover,

potatoes, and wheat. It is an excellent rotation when early planted

potatoes or silage corn follows the sod, favoring the wheat in which

the clover again is seeded. The ground is plowed only once in three

years. The clover furnishes hay for the farm, and organic matter with

nitrogen for the land. There are two cash crops in the rotation when

potatoes are grown, and that makes a heavy draft upon fertility.

Experience has demonstrated that commercial fertilizers or manure

become necessary as a supplement to clover in a three years' rotation

embracing potatoes. This rotation gives good control of most weeds and

insect enemies.

Where wheat is unprofitable, the oat crop is used in its stead. If

mixed hay is wanted, timothy is sown with the clover. This is poor

practice from the standpoint of soil fertility because the draft upon

humus is heavy in a close rotation embracing a tilled crop and small

grain. The sod should be chiefly clover, or manure should be used in

connection with commercial fertilizer.

Grain and Clover.--In the case of some soils it is possible to grow a

wheat or corn crop each year, clover being grown as a catch crop. In

the long run, this practice will fail because the clover will cease to

make a thrifty growth when grown so nearly continuously. It succeeds

best on fertile land.

Potatoes and Crimson Clover.--In some potato-producing sections in warm

latitudes it is a not uncommon practice to grow potatoes year after

year on the same land, seeding to crimson clover after the removal of

the crop in August, and plowing the clover down early in the spring.

Rye has been similarly used farther north. In each instance available

plant-food must be freely supplied. The practice is a temporary

expedient of value, but probably cannot be pursued indefinitely with

profit. This is likewise true of similar close rotations.

CHAPTER XVI

THE NEED OF COMMERCIAL FERTILIZERS

Loss of Plant-food.--The soil is composed chiefly of material that

never will enter into the structure of plants, but that serves us by

affording a congenial place for plant-roots. It anchors the plants,

holds moisture for them, and offers opportunity for all the processes

necessary to the preparation of plant-food and to its use. In this

material are the abundant supplies of such plant-food as silica, but,

as has been previously stated, their very abundance leads us rightly to

disregard them in our thinking. Our interest is only in the very small

percentage of material that is composed of the four constituents which

may be lacking in available form in the soil: nitrogen, phosphoric

acid, potash, and lime. We believe that the only consideration that now

need be given lime is as a soil-corrective and, when there is no

acidity, we may assume that there is plenty of lime present. When

yields of crops tend to decrease, the only plant-foods with which we

are concerned are nitrogen, phosphoric acid, and potash.

The materials were stored in all agricultural land, and much of the

supply is in inert forms. They help to make what we call the natural

strength of the land. The rotting of organic matter, tillage, and many

other agencies bring about some availability. The removal of crops,

leaching, etc., reduce the supply. The right use of commercial

fertilizers involves the addition of some plant-food when the available

supply in a particular soil is inadequate.

Prejudice against Commercial Fertilizers.--The owner of land that was

made very fertile by nature, and that has not been cropped long enough

to reduce the supply of available fertility to the danger-point, rarely

fails to entertain a prejudice against commercial fertilizers. It is

the rule that he refuses to consider their use until the decrease in

crop yields becomes so serious that necessity drives. If his land is

not contributing its fair share of grain, vegetables, etc., to the

markets, but has all its products converted into meat or milk, the

supply of available plant-food may remain sufficient for so long a time

that the matter cannot have any interest for him. If the land is

producing some crops for market, there is reduction in its mineral

store. It is the rule that the boundary of profitable use of commercial

fertilizers pushes westward from the older and naturally poorer

seaboard states about one generation after need shows in the crop

yields. Lack of knowledge, the association of the use of commercial

fertilizers with poor land, and some observation of the unwise use of

fertilizers, combine to create a lively prejudice. They are viewed as

stimulants only, and costly ones at that.

Are Fertilizers Stimulants?--Some words carry with them their own

popular condemnation. We are accustomed to draw a sharp line between

foods and stimulants, and to condemn the latter. To stimulate is to

rouse to activity. Tillage does not add one pound of plant-food to the

soil, and its office is to enable plants to draw material out of the

soil. It makes activities possible that convert soil material into

crops. Fertilizers add plant-food directly to the soil, and it is also

to their credit that their judicious use favors increased availability

in some of the compounds already in the soil. The greater part of the

labor put on land is designed to make plant-food available, either by

providing moisture, or ease of penetration of plant-roots, or activity

of bacteria, or other means that will permit plants to remove what they

need for growth. Fertilizers supply fertility directly and indirectly,

but it is their direct service in meeting a deficiency in plant-food

that affords all needed justification for their use by practical

farmers.

Referring to the thirty years' soil fertility experiments of the

Pennsylvania station, Hunt says that they "show that there is nothing

injurious about commercial fertilizers. For thirty years certain plats

in this experiment have received no stable manures. No organic matter

has been added to the soil except that which was furnished by the roots

and stubble of plants grown. These plats are not only as fertile as

they were thirty years ago, but they have yielded, and continue to

yield, as good crops as adjacent plats which have received yard manure

every two years in place of commercial fertilizer."

Soil Analysis.--There is wide misconception regarding the value of

chemical analysis of the soil as an aid in making choice of a

fertilizer. Analysis has shown that some soil types are relatively

richer in plant-constituents than are others, and it has shown abnormal

deficiency in some types of limited area. It has given us more

knowledge of soils, but as a guide to fertilization in particular

instances it usually has no value. The samples used by an analyst are

so small that the inaccuracy in his determination may easily be greater

than the total amount of plant-food in a very heavy application of

commercial fertilizer. A field that has been reduced to temporarily low

productive power by heavy cropping or bad farming methods may show a

greater content of plant-food than another field that is in a highly

productive condition. This is a fact difficult of acceptance by some

who want the aid of science, but such are the present limitations. The

weight of a fertilizer application is so small in comparison with the

weight of the surface part of an acre of land that the use of a ton of

fertilizer may not be detected in the analyst's determinations, and

moreover his determinations of actual availability in the soil's

supplies are not serviceable in the selection of a fertilizer for any

particular field and crop.

Physical Analysis.--Chemical analysis is costly and unsatisfactory as a

guide to fertilization. Physical analysis by a competent man may have

distinct value, and especially to one lacking experience with his soil.

The mapping of soils by national and state authorities has given pretty

accurate knowledge of hundreds of soil types, their location and

characteristics, and when a soil expert obtains a sample of soil and

the history of its past treatment, he can assign it to its type and

give to its owner dependable advice regarding its crop-adaptation and

probable fertilizer requirements.

The Use of Nitrogen.--There is no fully satisfactory way of determining

the kind and amount of fertilizer that should be used at any particular

time for any one crop. Perfection in this respect is no easier in

attainment than in other matters. There are, however, means of arriving

at conclusions that are a valuable guide.

In a general way, nitrogen is in scant supply in all worn soils.

Wherever the cropping has been hard, and manure has not gone back to

the land, the growth in stalk and leaves of the plant is deficient. The

color is light. Inability of a soil to produce a strong growth of corn,

a large amount of straw, or a heavy hay crop, is indicative of lack of

nitrogen in nearly every instance.

The legumes, such as clover, and the stable manures are rich in

nitrogen, and when the scheme of farming involves their use on all the

land of the farm, no need of purchased nitrogen may arise in the

production of staple crops. In the black corn soils the nitrogen

content originally was high.

Lands that naturally are not very fertile rarely have enough available

nitrogen. Where timothy is a leading crop, the demand for nitrogen is

heavy. A cold spring or summer, checking nature's processes in the

soil, may cause a temporary deficiency in available nitrogen in land

that usually has a sufficient supply. Associating a rank growth of

stalk and leaf with an abundance of nitrogen, the experienced man can

form a pretty safe opinion regarding the probable profitableness of an

investment in this element. It costs nearly four times as much per

pound as either of the two other constituents of a fertilizer, and so

far as is feasible it should be obtained through the legumes and stable

manure.

Phosphoric-acid Requirements.--Soil analyses show that the content of

phosphoric acid in most soils of this country is relatively small. The

results of experiments with the various constituents of fertilizers are

in accord with this fact. Fertilizer experiments at the various

stations and on farms are nearly a unit in showing that if any need in

plant-food exists, phosphoric acid is deficient. When crop-producing

power decreases, and the farmer begins to seek a commercial fertilizer

to repair the loss, he finds that bone-dust or acid phosphate is

serviceable. The resulting increase in yield often leads to such sole

dependence upon this fertilizer that clover and manure are disregarded,

the percentage of humus is allowed to drop, and finally the fertilizer

is brought into disrepute. The need of phosphoric acid is so common

that it is the sole plant-food in much fertilizer, and the dominant

element in practically all the remainder on the market.

[Illustration: Plat experiments.]

The Need of Potash.--Land which is deficient in organic matter

ordinarily is lacking in available potash, and responds with profit to

applications, provided the nitrogen and phosphoric-acid requirements

have been met. Clay soils contain far more potash than sandy soils, and

in a farming scheme for them that permits the use of manure and clover,

it may not become necessary to buy much potash. The liberal use of

straw in the stables, and the saving of all the liquid manure, are

helps. Farms from which the hay and straw have been sold for a long

period of time develop an urgent need of potash. Much muck land is very

deficient in this constituent.

Fertilizer Tests.--Every farmer should conduct some fertilizer tests

for himself. It is only the soil itself that can make an adequate reply

to a question regarding its needs. The test should be made under

conditions furnishing evenness in the soil, and it should be continued

for years. There is pleasure to an intelligent farmer in such

questioning of his soil, and only in this way can assurance be obtained

that the investment in fertilizers is the wisest that can be planned

for the farm.

There are only three plant constituents to be tested, but they must be

used in combination as well as singly. A soil that is deficient in the

three may not give any return from potash alone, and usually does not,

although it may give a marked increase from use of phosphoric acid

alone. The plats may be eight rods long and one rod wide, containing

each one twentieth of an acre, and having strips two feet wide

separating them. The following chart suggests quantities of fertilizers

to be used on the one-twentieth acre plats, 10 in number:

+---------------------------------------+

| Nothing. |

+---------------------------------------+

| 5 pounds nitrate of soda. |

+---------------------------------------+

| 18 pounds 14 per cent acid phosphate. |

+---------------------------------------+

| 4 pounds muriate of potash. |

+---------------------------------------+

| Nothing. |

+---------------------------------------+

| 5 pounds nitrate of soda. |

| 18 pounds 14 per cent acid phosphate. |

+---------------------------------------+

| 5 pounds nitrate of soda. |

| 4 pounds muriate of potash. |

+---------------------------------------+

| 18 pounds 14 per cent acid phosphate. |

| 4 pounds muriate of potash. |

+---------------------------------------+

| 5 pounds nitrate of soda. |

| 18 pounds 14 per cent acid phosphate. |

| 4 pounds muriate of potash. |

+---------------------------------------+

| Nothing. |

+---------------------------------------+

Variation in Soil.--The difficulty in determining the character of

fertilizer for a field, due to variation in the soil, is overestimated.

Very often a land-owner says, "I have a dozen kinds of soil in every

field." This is true in a way, it may be, but if all the field has had

the same treatment in the past, the probability is that the fertilizer

which is best for one part of the field will be quite good for the

other parts. The likeness in characteristics that permits the land to

be cropped as one field gives some assurance of likeness in plant-food

needs, even where the proportion of clay and sand varies and the color

is not the same.

There may be wide variation in the productive power of the fields of a

farm, due to the treatments they have received. The land that grows

heavy clover in a close rotation, or receives all the stable manure,

may need neither nitrogen nor potash, while another field, hard-run by

timothy and corn, may need a complete fertilizer. When a careful

fertilizer test on land of only average productive power has been made,

the owner has some definite knowledge of his soil that enables him to

give more intelligent treatment to all his fields than was possible

before the test had been made. He observes the appearance and yield of

plants where the plant-food requirement was fully met, and makes

allowance in other fields for gains or losses in the soil due to

different treatment. It is out of the question to become discouraged

before a beginning has been made. If yields are limited by absence of

plant-food, fertilizers must be used. If money must be expended for

fertilizers, it is only good business to know that the money is

expended to the best advantage.

CHAPTER XVII

COMMERCIAL SOURCES OF PLANT-FOOD

Acquaintance with Terms.--The hesitation of many users of commercial

fertilizer to master the few technical terms used in analyses of the

goods, for which over one hundred million dollars annually are expended

in this country, is to be deplored. The number of the materials

available for any large use as sources of plant-food in a commercial

fertilizer is small, and something of their characteristics should be

known. Every farmer should have a working knowledge of these

materials--their sources, the percentage of plant-food carried by them,

and their probable availability. He should know in a general way their

advantages and disadvantages in comparison with each other.

Nitrate of Soda.--One of the best carriers of nitrogen is nitrate of

soda, which is imported from Chili, South America, where great beds

exist. The most of the impurities are removed, and the nitrate of soda

comes to us in bags holding 200 pounds, and looks much like discolored

salt. It is easily soluble in water, and usually contains a little over

15 per cent of nitrogen, which is in a very available form. Its

immediate availability brings it into use by gardeners and truckers,

and it is an excellent source of nitrogen for grass fertilizers to be

used in the early spring. It was formerly advised that nitrate of soda

should not form part of a fertilizer for use before plant-roots had

filled the ground, its high availability being supposed to lead to

heavy loss by leaching. The Pennsylvania experiment station uses it as

its sole source of nitrogen in fertilizers for staple crops on its 900

acres of farm land. It is effective in fertilizers for corn, wheat,

potatoes, and grass, as well as for special crops.

The warnings regarding loss by leaching should not be disregarded,

however. If the price of nitrogen in an organic form were as low as it

has been in nitrate of soda, and if the soils of the Pennsylvania

station farms were sandy, the use of nitrate of soda as the sole

carrier of nitrogen would be inadvisable. The only fact of consequence

is that the danger of loss has been over-stated, turning some farmers

away from the use of a good and relatively cheap carrier of nitrogen.

Sulphate of Ammonia.--This is a by-product in the manufacture of coke

and also of illuminating gas. Hunt estimates that the amount of

nitrogen lost annually in Pennsylvania's coke industry would be

sufficient, if recovered by proper type of ovens, to furnish every acre

of land under cultivation in the state with four fifths of all the

nitrogen needed to keep it in a maximum state of fertility.

Sulphate of ammonia contains about 20 per cent of nitrogen, which is in

a quite available form. It has a tendency to exhaust the lime in the

soil, producing an acid condition. Some plats in the fertilizer

experiment at the Pennsylvania station have received their nitrogen in

the form of sulphate of ammonia for 30 years, and are now in such acid

condition that no crops thrive upon them. The corrective, of course, is

lime, and if ammonium sulphate were somewhat lower in price, its use

would be profitable, justifying cost of correction of acidity if it

should occur. It is used by manufacturers of commercial fertilizers,

and is well adapted to mixtures on account of its physical condition.

Dried Blood.--There is no more satisfactory source of organic nitrogen

than dried blood of high grade. The best blood, red in color, contains

nearly as much nitrogen as nitrate of soda, running from 13 to 15 per

cent. The nitrogen is not as quickly available as that in the nitrate,

but is more so than that in any other form of organic nitrogen. One

would rarely go amiss in the purchase of dried blood as a carrier of

nitrogen if the price were relatively as low as in the case of nitrate

of soda, but he should not let any prejudice in favor of animal origin

of fertilizers lead him to pay an excessive price per pound for the

nitrogen contained in it. Such a prejudice has caused the nitrogen in a

good red blood to sell for one half more per pound than in nitrate of

soda, and it is not a good purchase on that basis.

The lower grades of dried blood on the market contain as low as 6 per

cent of nitrogen, and the animal refuse put into it gives it a content

of a few per cent of phosphoric acid. This black blood is very variable

in composition, and should always be accompanied by a guaranteed

analysis.

Tankage.--The waste from the slaughter of animals goes into a product

called tankage. The refuse is cooked for removal of the fat, and then

ground. It may run high in nitrogen on account of the amount of meat in

the mixture, and it may be low in nitrogen and very high in phosphoric

acid by reason of the large amount of bone in the mixture. Only a

guarantee of analysis affords safety to the buyer. It is a relatively

slow and good fertilizer, and is used usually in connection with forms

of plant-food that are more quickly available.

Fish.--Near the Atlantic coast a large quantity of ground fish, after

the extraction of oil, is used as a fertilizer, but the cost of the

nitrogen and phosphoric acid in this carrier is relatively too high to

justify its free use. Like dried blood, its organic character gains for

it a popularity that does not have full justification in fact.

Animal Bone.--The original source of phosphoric acid as a fertilizer

was animal bone, just as hard-wood, unleached ashes were the source of

potash. The organic character of the animal bone made it appear more

truly a manure than could any rock or other inorganic substance. There

is no more satisfactory source of phosphoric acid than animal bone, and

if it were in full supply for the needs of soils, there would be little

occasion to discuss the merits of rock-phosphate and other similar

materials. The supply is a small fraction of the need. If all animal

bone were carefully saved and returned to the land that produced all of

our animals, it would return to the soil only what those animals

carried away in their bones, and that is indeed a small fraction of all

the draft our crops make upon the soil's supply of this one substance.

Some of the best animal bone goes into the manufacture of articles that

never contribute anything to the soil, and there are other sources of

loss. The supply of phosphoric acid from bone is too small, when

compared with the land's need, to deserve more than a small fraction of

the consideration it receives by users of commercial fertilizers.

Seed-mixtures.--When grass is wanted for hay as well as fertility, the