Crops and Methods for Soil Improvement Part 6

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 lat.i.tudes 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 gra.s.s 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 ma.s.s 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, a.s.suming 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 lat.i.tudes. 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 gra.s.s 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 ma.s.s 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 a.s.sociated 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 a.s.sent 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.

[Ill.u.s.tration: 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 coa.r.s.e 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 coa.r.s.e 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 gra.s.s, hay, stalks, by-products in manufacture, and coa.r.s.e 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 a.n.a.lysis shows that the nitrogen, phosphoric acid, and potash contained in it are worth that sum when valued at the market prices of those plant const.i.tuents. 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 const.i.tuent, 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 const.i.tuents.

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.

[Ill.u.s.tration: 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 a.s.sumes 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.

a.n.a.lysis 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 const.i.tuents in fresh excrements of farm animals, the solid and liquid being mixed:

+----------+----------+------------+----------+ | Animal | Per Cent | Per Cent | Per Cent | | | Nitrogen | Phosphoric | Potash | | | | Acid | | +----------+----------+------------+----------+ | 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 coa.r.s.e 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.

[Ill.u.s.tration: 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 const.i.tuents 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 a.s.sist 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 lat.i.tudes 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 ma.s.s can be kept firm by the tramping of the animals. It may be necessary to add some water at intervals to keep the ma.s.s sufficiently moist. The water excludes air and a.s.sists 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 ma.s.s.

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 gra.s.s, 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 quant.i.ties 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 quant.i.ties 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 quant.i.ties 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.