How may silica be rendered soluble?What is the condition of chlorine in the soil?Do peroxide and protoxide of iron affect plants in the same way?How would you treat a soil containing protoxide of iron?On what does the usefulness of all these matters in the soil depend?
How may silica be rendered soluble?
What is the condition of chlorine in the soil?
Do peroxide and protoxide of iron affect plants in the same way?
How would you treat a soil containing protoxide of iron?
On what does the usefulness of all these matters in the soil depend?
Theneutrals, silica, chlorine, oxide of iron, and oxide of manganese, deserve a careful examination. Silica exists in the soil usually in the form ofsand,in which it is, as is well known, perfectly insoluble; and, before it can be used by plants, which often require it in large quantities, it must be made soluble, which is done by combining it with an alkali.
For instance, if the silica in the soil is insoluble, we must make an application of an alkali, such as potash, which will unite with the silica, and form the silicate of potash, which is in the exact condition to be dissolved and carried into the roots of plants.
Chlorine in the soil is probably always in an available condition.
Oxide of iron exists, as has been previously stated, usually in the form of theperoxide (or red oxide). Sometimes, however, it exists in the form of theprotoxide (or black oxide), which is poisonous to plants, and renders the soil unfertile. By loosening the soil in such a manner as to admit air and water, this compound takes up more oxygen, which renders it a peroxide, and makes it available for plants. The oxide of manganese is probably of little consequence.
The usefulness of all of these matters in the soil depends on theirexposure; if they are in theinteriorof particles, they cannot be made use of; while, if the particles are so pulverized that their constituents are exposed, they become available, because water can immediately attack to dissolve, and carry them into roots.
What is one of the chief offices of plowing and hoeing?Is the subsoil usually different from the surface soil?What circumstances have occasioned the difference? In what way?
What is one of the chief offices of plowing and hoeing?
Is the subsoil usually different from the surface soil?
What circumstances have occasioned the difference? In what way?
This is one of the great offices of plowing and hoeing; thelumpsof soil being thereby more broken up and exposed to the action of atmospheric influences, which are often necessary to produce a fertile condition of soil, while the trituration of particles reduces them in size.
May the subsoil be made to resemble the surface soil?May all soils be brought to the highest state of fertility?On what examination must improvement be based?What is the difference between the soil of some parts of Massachusetts and that of the Miami valley?
May the subsoil be made to resemble the surface soil?
May all soils be brought to the highest state of fertility?
On what examination must improvement be based?
What is the difference between the soil of some parts of Massachusetts and that of the Miami valley?
The subsoil is usually of a different character from the surface soil, but this difference is more often the result of circumstances than of formation. The surface soil from having been long cultivated has been more opened to the influences of the air than is the case with the subsoil, which has never been disturbed so as to allow the same action. Again the growth of plants has supplied the surface soil with roots, which by decaying have given it organic matter, thus darkening its color, rendering it warmer, and giving greater ability to absorb heat and moisture, and to retain manures. All of these effects render the surface soil of a more fertile character than it was before vegetable growth commenced; and, where frequent cultivation and manures have been applied, a still greater benefit has resulted. In most instances the subsoil may by the same meansbe gradually improved in condition until it equals the surface soil in fertility. The means of producing this result, also farther accounts of its advantages, will be given under the head ofCultivation(Sect. IV.)
From what has now been said of the character of the soil, it must be evident that, as we know thecausesof fertility and barrenness, we may by the proper means improve the character of all soils which are not now in the highest state of fertility.
Chemical analysis will tell us thecompositionof a soil, and an examination, such as any farmer may make, will inform us of its deficiencies inmechanicalcharacter, and we may at once resort to the proper means to secure fertility. In some instances the soil may contain every thing that is required, but not in the necessary condition. For instance, in some parts of Massachusetts, there are nearlybarrensoils which show by analysis precisely the same chemical composition as the soil of the Miami valley of Ohio, one of the mostfertilein the world. The cause of this great difference in their agricultural capabilities, is that the Miami soil has its particlesfinely pulverized; while in the Massachusetts soil the ingredients are combined within particles (such as pebbles, etc.), where they are out of the reach of roots.
Why do soils of the same degree of fineness sometimes differ in fertility?Can soils always be rendered fertile with profit?Can we determine the cost before commencing the work?What must be done before a soil can be cultivated understandingly?What must be done to keep up the quality of the soil?
Why do soils of the same degree of fineness sometimes differ in fertility?
Can soils always be rendered fertile with profit?
Can we determine the cost before commencing the work?
What must be done before a soil can be cultivated understandingly?
What must be done to keep up the quality of the soil?
In other cases, we find two soils, which are equally well pulverized, and which appear to be of the same character, having very different power to support crops. Chemical analysis will show in these instances a difference of composition.
All of these differences may be overcome by the use of the proper means. Sometimes it could be done at an expense which would be justified by the result; and, at others, it might require too large an outlay to be profitable. It becomes a question of economy, not of ability, and science is able to estimate the cost.
Soil cannot be cultivated understandingly until it has been subjected to such an examination as will tell us exactly what is necessary to render it fertile. Even after fertility is perfectly restored it requires thought and care to maintain it. The ingredients of the soil must be returned in the form of manures as largely as they are removed by the crop, or the supply will eventually become too small for the purposes of vegetation.
FOOTNOTES:[T]It is due to our country, as well as to Prof. Mapes and others, who long ago explained this absorptive power of clay and carbon, to say that the subject was perfectly understood and practically applied in America a number of years before Prof. Way published the discovery in England as original.
[T]It is due to our country, as well as to Prof. Mapes and others, who long ago explained this absorptive power of clay and carbon, to say that the subject was perfectly understood and practically applied in America a number of years before Prof. Way published the discovery in England as original.
[T]It is due to our country, as well as to Prof. Mapes and others, who long ago explained this absorptive power of clay and carbon, to say that the subject was perfectly understood and practically applied in America a number of years before Prof. Way published the discovery in England as original.
What must a farmer know in order to avoid failures?Can this be learned entirely from observation?What kind of action have manures?Give examples of each of these.May mechanical effects be produced by chemical action?How does potash affect the soil?
What must a farmer know in order to avoid failures?
Can this be learned entirely from observation?
What kind of action have manures?
Give examples of each of these.
May mechanical effects be produced by chemical action?
How does potash affect the soil?
To understand the science ofmanuresis the most important branch of practical farming. No baker would be called a good practical baker who kept his flour exposed to the sun and rain. No shoemaker would be called a good practical shoemaker, who used morocco for the soles of his shoes, and heavy leather for the uppers. No carpenter would be called a good practical carpenter, who tried to build a house without nails, or other fastenings. So with the farmer. He cannot be called a good practical farmer if he keeps the materials, from which he is to make plants, in such a condition, that they will have their valuedestroyed, uses them in the wrong places, or tries to put them together without having every thing present that is necessary. Before he can avoid failureswith certainty, he must know what manures are composed of, how they are to be preserved, where they are needed, and what kinds are required. True, he may from observation and experience,guessat results, but he cannotknowthat he is right until he has learned the facts above named. In this section of our work, we mean to convey some of the information necessary to this branch ofpractical farming.
We shall adopt a classification of the subject somewhat different from that found in most works on manures, but thefactsare the same. The action of manures is eithermechanicalorchemical, or a combination of both. For instance: some kinds of manure improve the mechanical character of the soil, such as those which loosen stiff clay soils, or others which render light sandy soils compact—these are calledmechanicalmanures. Some again furnish food for plants—these are calledchemicalmanures.
Many mechanical manures produce their effects by means of chemical action. Thuspotashcombines chemically with sand in the soil. In so doing, itroughens the surfaces of the particles of sand, and renders the soil less liable to be compacted by rains. In this manner, it acts as amechanicalmanure. The compound of sand and potash,[U]as well as the potash alone, may enter into the composition of plants, and hence it is achemicalmanure. In other words, potash belongs to both classes described above.
It is important that this distinction should be well understood by the learner, as the words "mechanical" and "chemical" in connection with manures will be made use of throughout the following pages.
What are absorbents?What kind of manure is charcoal?
What are absorbents?
What kind of manure is charcoal?
There is another class of manures which we shall callabsorbents. These comprise those substances which have the power of taking up fertilizing matters, and retaining them for the use of plants. For instance,charcoalis an absorbent. As was stated in the section on soils, this substance is a retainer of all fertilizing gases and many minerals. Other matters made use of in agriculture have the same effect. These absorbents will be spoken of more fully in their proper places.
TABLE.
Into what classes may manures be divided?What are organic manures?Inorganic? Atmospheric?
Into what classes may manures be divided?
What are organic manures?
Inorganic? Atmospheric?
Manures may be divided into three classes, viz.:organic,inorganic, andatmospheric.
Organicmanures comprise allanimalandvegetablematters which are used to fertilize the soil, such as dung, muck, etc.
Inorganicmanures are those which are of a purelymineralcharacter, such as lime, ashes, etc.
Atmosphericmanures consist of those organic manures which are in the form of gases in the atmosphere, and which are absorbed by rains and carried to the soil. These are of immense importance. The ammonia and carbonic acid in the air are atmospheric manures.
FOOTNOTES:[U]Silicate of potash.
[U]Silicate of potash.
[U]Silicate of potash.
Of what is animal excrement composed?Explain the composition of the food of animals.What does hay contain?To what does Liebig compare the consumption of food by animals, and why?
Of what is animal excrement composed?
Explain the composition of the food of animals.
What does hay contain?
To what does Liebig compare the consumption of food by animals, and why?
The first organic manure which we shall examine, is animalexcrement.
This is composed of those matters which have been eaten by the animal as food, and have been thrown off as solid or liquid manure. In order thatwe may know of what they consist, we must refer to the composition of food and examine the process of digestion.
The food of animals, we have seen to consist of both organic and inorganic matter. The organic part may be divided into two classes,i. e., that portion which contains nitrogen—such as gluten, albumen, etc., and that which does not contain nitrogen—such as starch, sugar, oil, etc.
The inorganic part of food may also be divided intosolublematter andinsolublematter.
Of what does that part of dung consist which resembles soot?What else does the dung contain?In what manner does the digested part of food escape from the body?
Of what does that part of dung consist which resembles soot?
What else does the dung contain?
In what manner does the digested part of food escape from the body?
Let us now suppose that we have a full-grown ox, which is not increasing in any of his parts, but only consumes food to keep up his respiration, and to supply the natural wastes of his body. To this ox we will feed a ton of hay which contains organic matter, with and without nitrogen, and soluble and insoluble inorganic substances. Now let us try to follow it through its changes in the animal, and observe its destination. Liebig compares the consumption of food by animals to the imperfect burning of wood in a stove, where a portion of the fuel is resolved into gases and ashes (that is, it is completely burned), andanother portion, which is not thoroughly burned, passes off assoot. In the animal action in question, the food undergoes changes which are similar to this burning of wood. A part of the food isdigestedand taken up by the blood, while another portion remains undigested, and passes the bowels as solid dung—corresponding to soot. This part of the dung then, we see is merely so much of the food as passes through the system without being materially changed. Its nature is easily understood. It contains organic and inorganic matter in nearly the same condition as they existed in the hay. They have been rendered finer and softer, but their chemical character is not materially altered. The dung also contains small quantities of nitrogenous matter, whichleaked out, as it were, from the stomach and intestines. The digested food, however, undergoes further changes which affect its character, and it escapes from the body in three ways—i. e., through the lungs, through the bladder, and through the bowels. It will be recollected from the first section of this book, p. 22, that the carbon in the blood of animals, unites with the oxygen of the air drawn into the lungs, and is thrown off in the breath as carbonic acid. The hydrogen and oxygen unite to form a part of the water which constitutes the moisture of the breath.
Explain the escape of carbon, hydrogen and oxygen.What becomes of the nitrogenous parts?How is thesolubleash of the digested food parted with?The insoluble?If any portions of the food are not returned in the dung, how are they disposed of?
Explain the escape of carbon, hydrogen and oxygen.
What becomes of the nitrogenous parts?
How is thesolubleash of the digested food parted with?
The insoluble?
If any portions of the food are not returned in the dung, how are they disposed of?
That portion of the organic part of the hay which has been taken up by the blood of the ox, and which does not contain nitrogen (corresponding to thefirstclass of proximates, as described inSect. I), is emitted through the lungs. It consists, as will be recollected, of carbon, hydrogen and oxygen, and these assume, in respiration, the form of carbonic acid and water.
The organic matter of the digested hay, in the blood, which contains nitrogen (corresponding to thesecondclass of proximates, described inSect. I), goes to thebladder, where it assumes the form of urea—a constituent of urine or liquid manure.
We have now disposed of the imperfectly digested food (dung), and of theorganicmatter which was taken up by the blood. All that remains to be examined is the inorganic or mineral matter in the blood, which would have becomeashes, if the hay had been burned. Thesolublepart of this inorganic matter passes into the bladder, and forms theinorganic part of urine. Theinsolublepart passes the bowels, in connection with the dung.
How is their place supplied?Is food put out of existence when it is fed to animals?What does the solid dung contain? Liquid manure? The breath?
How is their place supplied?
Is food put out of existence when it is fed to animals?
What does the solid dung contain? Liquid manure? The breath?
If any of the food taken up by the blood is not returned as above stated, it goes to form fat, muscle, hair, bones, or some other part of the animal, and ashe is not growing (not increasing in weight) an equivalent amount of the body of the animal goes to the manure to take the place of the part retained.[V]
We now have our subject in a form to be readily understood. We learn that when food is given to animals it is notput out of existence, but is merelychanged in form; and that in the impurities of the breath, we have a large portion of those parts of the food which plants obtain from air and from water; while the solid and liquid excrements contain all that was taken by the plants from the soil and manures.
TheSolid Dungcontains the undigested parts of the food, theinsolubleparts of the ash, and the nitrogenous matters which haveescapedfrom the digestive organs.
"Liquid Manure" the nitrogenous orsecond classof proximates of thedigested food, and thesolubleparts of the ash.
The Breathcontains thefirst classof proximates, those which contain carbon, hydrogen and oxygen, butno nitrogen.[W]
FOOTNOTES:[V]This account of digestion is not, perhaps, strictly accurate in a physiological point of view, but it is sufficiently so to give an elementary understanding of the character of excrements as manures.[W]The excrements of animals contain more or less of sulphur, and sometimes small quantities of phosphorus.
[V]This account of digestion is not, perhaps, strictly accurate in a physiological point of view, but it is sufficiently so to give an elementary understanding of the character of excrements as manures.
[V]This account of digestion is not, perhaps, strictly accurate in a physiological point of view, but it is sufficiently so to give an elementary understanding of the character of excrements as manures.
[W]The excrements of animals contain more or less of sulphur, and sometimes small quantities of phosphorus.
[W]The excrements of animals contain more or less of sulphur, and sometimes small quantities of phosphorus.
What are the first causes of loss of manure?What isevaporation?
What are the first causes of loss of manure?
What isevaporation?
The loss of manure is a subject which demands most serious attention. Until within a few years, little was known about the true character of manures, and consequently, of the importance of protecting them against loss.
The first causes of waste areevaporationandleaching.
Name a solid body which evaporates.What takes place when a dead animal is exposed to the atmosphere for a sufficient time?What often assist the evaporation of solids?
Name a solid body which evaporates.
What takes place when a dead animal is exposed to the atmosphere for a sufficient time?
What often assist the evaporation of solids?
Evaporation is the changing of a solid or liquid body to a vapory form. Thus common smelling salts, a solid, if left exposed, passes into the atmosphere inthe form of a gas or vapor. Water, a liquid, evaporates, and becomes a vapor in the atmosphere. This is the case with very many substances, and in organic nature, both solid and liquid, they are liable to assume a gaseous form, and become mixed with the atmosphere. They are not destroyed, but are merely changed in form.
As an instance of this action, suppose an animal to die and to decay on the surface of the earth. After a time, the flesh will entirely disappear, but is not lost. It no longer exists as the flesh of an animal, but its carbon, hydrogen, oxygen, and nitrogen, still exist in the air. They have been liberated from the attractions which held them together, and have passed away; but (as we already know from what has been said in a former section) they are ready to be again taken up by plants, and pressed into the service of life.
The evaporation of liquids may take place without the aid of any thing but heat; still, in the case of solids, it is often assisted by decay and combustion, which break up the bonds that hold the constituents of bodies together, and thus enable them to return to the atmosphere, from which they were originally derived.
What is the cause of odor?When we perceive an odor, what is taking place?Why do manures give off offensive odors?How may we detect ammonia escaping from manure?
What is the cause of odor?
When we perceive an odor, what is taking place?
Why do manures give off offensive odors?
How may we detect ammonia escaping from manure?
It must be recollected that every thing, which hasanodor(or can be smelled), is evaporating. The odor is caused by parts of the body floating in the air, and acting on the nerves of the nose. This is an invariable rule; and, when we perceive an odor, we may be sure that parts of the material, from which it emanates, are escaping. If we perceive the odor of an apple, it is because parts of the volatile oils of the apple enter the nose. The same is true when we smell hartshorn, cologne, etc.
Manures made by animals have an offensive odor, simply because volatile parts of the manure escape into the air, and are therefore made perceptible. All organic parts in turn become volatile, assuming a gaseous form as they decompose.
We do not see the gases rising, but there are many ways by which we can detect them. If we wave a feather over a manure heap, from which ammonia is escaping, the feather having been recently dipped in manure, white fumes will appear around the feather, being the muriate of ammonia formed by the union of the escaping gas with the muriatic acid. Not only ammonia, but also carbonic acid, and other gases which are useful to vegetation escape, and are given to the winds. Indeed it may be stated in few words that all of the organic part ofplants(all that was obtained from the air, water, and ammonia),constituting more than nine tenths of their dry weight, may be evaporated by the assistance of decay or combustion. The organic part ofmanuresmay be lost in the same manner; and, if the process of decomposition be continued long enough, nothing but a mass of mineral matter will remain, except perhaps a small quantity of carbon which has not been resolved into carbonic acid.
What remains after manure has been long exposed to decomposition?What gaseous compounds are formed by the decomposition of manures?
What remains after manure has been long exposed to decomposition?
What gaseous compounds are formed by the decomposition of manures?
The proportion of solid manure lost by evaporation (made by the assistance of decay), is a very large part of the whole. Manure cannot be kept a single day in its natural state without losing something. It commences to give out an offensive odor immediately, and this odor is occasioned, as was before stated, by the loss of some of its fertilizing parts.
Animal manure contains, as will be seen by reference to p.100, all of the substances contained in plants, though not always in the correct relative proportions to each other. When decomposition commences, the carbon unites with the oxygen of the air, and passes off as carbonic acid; the hydrogen and oxygen combine to form water (which evaporates), and thenitrogen is mostly resolved into ammonia, which escapes into the atmosphere.
Describe fire-fanging.What takes place when animal manure is exposed in an open barn-yard?What does liquid manure lose by evaporation?
Describe fire-fanging.
What takes place when animal manure is exposed in an open barn-yard?
What does liquid manure lose by evaporation?
If manure is thrown into heaps, it often ferments so rapidly as to produce sufficient heat to set fire to some parts of the manure, and cause it to be thrown off with greater rapidity. This may be observed in nearly all heaps of animal excrement. When they have lain for some time in mild weather, gray streaks ofashesare often to be seen in the centre of the pile. The organic part of the manure having beenburnedaway, nothing but the ash remains,—this is calledfire-fanging.
Manures kept in cellars without being mixed with refuse matter are subject to the same losses.
When kept in the yard, they are still liable to be lost by evaporation. They are here often saturated with water, and this water in its evaporation carries away the ammonia, and carbonic acid which it has obtained from the rotting mass. The evaporation of the water is rapidly carried on, on account of the great extent of surface. The whole mass is spongy, and soaks the liquids up from below (through hollow straws, etc.), to be evaporated at the surface on the same principle as causes the wick of a lamp to draw up the oil to supply fuel for the flame.
Liquid Manurecontaining large quantities of nitrogen, and forming much ammonia, is also liable to lose all of its organic part from evaporation (andfermentation), so that it is rendered as much less valuable as is the solid dung.[X]
When does the waste of exposed manure commence?What does economy of manure require?What is the effect of leaching?Give an illustration of leaching.
When does the waste of exposed manure commence?
What does economy of manure require?
What is the effect of leaching?
Give an illustration of leaching.
From these remarks, it may be justly inferred that a very large portion of thevalueof solid and liquid manure as ordinarily kept is lost by evaporation in a sufficient length of time, depending on circumstances, whether it be three months or several years. The wasting commences as soon as the manure is dropped, and continues, except in very cold weather, until the destruction is complete. Hence we see that true economy requires that the manures of the stable, stye, and poultry-house, should be protected from evaporation (as will be hereafter described), as soon as possible after they are made.
The subject ofleachingis as important in considering theinorganicparts of manures as evaporation is to the organic, while leaching also affects the organic gases, they being absorbed by water in a great degree.
A good illustration of leaching is found in the manufacture of potash. When water is pouredover wood-ashes, it dissolves their potash which it carries through in solution, making ley. If ley is boiled to dryness, it leaves the potash in a solid form, proving that this substance had been dissolved by the water and removed from the insoluble parts of the ashes.
How does water affect decomposing manures?Does continued decomposition continue to prepare material to be leached away?How far from the surface of the soil may organic constituents be carried by water?
How does water affect decomposing manures?
Does continued decomposition continue to prepare material to be leached away?
How far from the surface of the soil may organic constituents be carried by water?
In the same way water in passing through manures takes up the soluble portions of the ash as fast as liberated by decomposition, and carries them into the soil below; or, if the water runs off from the surface, they accompany it. In either case they are lost to the manure. There is but a small quantity of ash exposed for leaching in recent manures; but, as the decomposition of the organic part proceeds, it continues to develope it more and more (in the same manner as burning would do, only slower), thus preparing fresh supplies to be carried off with each shower. In this way, while manures are largely injured by evaporation, the soluble inorganic parts are removed by water until but a small remnant of its original fertilizing properties remains.
What arrests their farther progress?What would be the effect of allowing these matters to filter downwards?What does evaporation remove from manure? Leaching?
What arrests their farther progress?
What would be the effect of allowing these matters to filter downwards?
What does evaporation remove from manure? Leaching?
It is a singular fact concerning leaching, that water is able to carry no part of the organic constituents of vegetables more than about thirty-four inches below the surface in a fertile soil. They would probably be carried to an unlimited distancein pure sand, as it contains nothing which is capable of arresting them; but, in most soils, the clay and carbon which they contain retain all of the ammonia; also nearly all of the matters which go to form the inorganic constituents of plants within about the above named distance from the surface of the soil. If such were not the case, the fertility of the earth must soon be destroyed, as all of those elements which the soil must supply to growing plants would be carried down out of the reach of roots, and leave the world a barren waste, its surface having lost its elements of fertility, while the downward filtration of these would render the water of wells unfit for our use. Now, however, they are all retained near the surface of the soil, and the water issues from springs comparatively pure.
Evaporationremoves from manure—
Carbon, in the form of carbonic acid.Hydrogen and oxygen, in the form of water.Nitrogen, in the form of ammonia.
Carbon, in the form of carbonic acid.
Hydrogen and oxygen, in the form of water.
Nitrogen, in the form of ammonia.
Leachingremoves from manure—
The soluble and most valuable parts of the ash in solution in water, besides carrying away some of the named above forms of organic matter.
The soluble and most valuable parts of the ash in solution in water, besides carrying away some of the named above forms of organic matter.
FOOTNOTES:[X]It should be recollected that every bent straw may act as a syphon, and occasion much loss of liquid manure.
[X]It should be recollected that every bent straw may act as a syphon, and occasion much loss of liquid manure.
[X]It should be recollected that every bent straw may act as a syphon, and occasion much loss of liquid manure.
What substances are called absorbents?What is the most important of these?What substances are called charcoal in agriculture?How is vegetable matter rendered useful as charcoal?
What substances are called absorbents?
What is the most important of these?
What substances are called charcoal in agriculture?
How is vegetable matter rendered useful as charcoal?
Before considering farther the subject of animal excrement, it is necessary to examine a class of manures known asabsorbents. These comprise all matters which have the power of absorbing, or soaking up, as it were, the gases which arise from the evaporation of solid and liquid manures, and retaining them until required by plants.
The most important of these is undoubtedlycarbonor charcoal.
Charcoal, in an agricultural sense, means all forms of carbon, whether as peat, muck, charcoal dust from the spark-catchers of locomotives, charcoal hearths, river and swamp deposits, leaf mould, decomposed spent tanbark or sawdust, etc. In short, if any vegetable matter is decomposed with the partial exclusion of air (so that there shall not be oxygen enough supplied to unite with all of the carbon), aportion of its carbon remains in the exact condition to serve the purposes of charcoal.
What is the first-named effect of charcoal? The second? Third? Fourth?Explain the first action.
What is the first-named effect of charcoal? The second? Third? Fourth?
Explain the first action.
The offices performed in the soil by carbonaceous matter were fully explained in a former section (p.79, Sect. 2), and we will now examine merely its action with regard to manures. When properly applied to manures, in compost, it has the following effects:
1. It absorbs and retains the fertilizing gases evaporating from decomposing matters.
2. It acts as adivisor, thereby reducing the strength (or intensity) of powerful manures—thus rendering them less likely to injure the roots of plants; and also increases their bulk, so as to preventfire fangingin composts.
3. It in part prevents the leaching out of the soluble parts of the ash.
4. It keeps the compost moist.
The first-named office of charcoal,i. e., absorbing and retaining gases, is one of the utmost importance. It is this quality that gives to it so high a position in the opinion of all who have used it. As was stated in the section on soils, carbonaceous matter seems to be capable of absorbing every thing which may be of use to vegetation. It is a grand purifier, and while it prevents offensive odors from escaping, it is at the same time storing its pores with food for the nourishment of plants.
Explain its action as a divisor.How does charcoal protect composts against injurious action of rains?How does it keep them moist?
Explain its action as a divisor.
How does charcoal protect composts against injurious action of rains?
How does it keep them moist?
2d. In its capacity as adivisorfor manures, charcoal should be considered as excellent in all cases, especially to use with strongly concentrated (or heating) animal manures. These, when applied in their natural state to the soil, are very apt to injure young roots by the violence of their action. When mixed with a divisor, such manures arediluted, made less active, and consequently less injurious. In composts, manures are liable, as has been before stated, to become burned by the resultant heat of decomposition; this is calledfire fanging, and is prevented by the liberal use of divisors, because, by increasing the bulk, the heat being diffused through a larger mass, becomes less intense. The same principle is exhibited in the fact that it takes more fire to boil a cauldron of water than a tea-kettle full.
3d. Charcoal has much power to arrest the passage of mineral matters in solution; so much so, that compost heaps, well supplied with muck, are less affected by rains than those not so supplied. All composts, however, should be kept under cover.
4th. Charcoal keeps the compost moist from the ease with which it absorbs water, and its ability to withstand drought.
What source of carbon is within the reach of most farmers?What do we mean by muck?Of what does it consist?How does it differ in quality?
What source of carbon is within the reach of most farmers?
What do we mean by muck?
Of what does it consist?
How does it differ in quality?
With these advantages before us, we must see the importance of an understanding of the modes forobtaining charcoal. Many farmers are so situated that they can obtain sufficient quantities of charcoal dust. Others have not equal facilities. Nearly all, however, can obtainmuck, and to this we will now turn our attention.
What is the first step in preparing muck for decomposition?With what proportion of the lime and salt mixture should it be composted?Why should this compost be made under cover?What is this called after decomposition?Why should we not use muck immediately after taking it from the swamp?
What is the first step in preparing muck for decomposition?
With what proportion of the lime and salt mixture should it be composted?
Why should this compost be made under cover?
What is this called after decomposition?
Why should we not use muck immediately after taking it from the swamp?
Bymuck, we mean the vegetable deposits of swamps and rivers. It consists of decayed organic substances, mixed with more or less earth. Its principal constituent iscarbon, in different degrees of development, which has remained after the decomposition of vegetable matter. Muck varies largely in its quality, according to the amount of carbon which it contains, and the perfection of its decomposition. The best muck is usually found in comparatively dry locations, where the water which once caused the deposit has been removed. Muck which has been long in this condition, is usually better decomposed than that which is saturated with water. The muck from swamps, however, may soon be brought to the best condition. It should be thrown out, if possible, at least one year before it is required for use (a less time may suffice, except in very coldclimates) and left, in small heaps or ridges, to the action of the weather, which will assist in pulverizing it, while, from having its water removed, its decomposition goes on more rapidly.
After the muck has remained in this condition a sufficient length of time, it may be removed to the barn-yard and composted with the lime and salt mixture (described on page115) in the proportion of one cord of muck to four bushels of the mixture. This compost ought to be made under cover, lest the rain leach out the constituents of the mixture, and thus occasion loss; at the end of a month or more, the muck in the compost will have been reduced to a fine pulverulent mass, nearly equal to charcoal dust for application to animal excrement. When in this condition it is calledpreparedmuck, by which name it will be designated in the following pages.
Muck should not be used immediately after being taken from the swamp, as it is then almost alwayssour, and is liable to produce sorrel. Itssournessis due toacidswhich it contains, and these must be rectified by the application of an alkali, or by long exposure to the weather, before the muck is suitable for use.
What proportions of lime and salt are required for the decomposing mixture?Explain the process of making it.Why should it be made under cover?
What proportions of lime and salt are required for the decomposing mixture?
Explain the process of making it.
Why should it be made under cover?
The lime and salt mixture, used in the decomposition of muck, is made in the following manner:
Recipe.—Takethreebushels of shell lime,hot from the kiln, or as fresh as possible, and slake it with water in whichonebushel of salt has been dissolved.
Care must be taken to use only so much water as is necessary to dissolve the salt, as it is difficult to induce the lime to absorb a larger quantity.
In dissolving the salt, it is well to hang it in a basket in the upper part of the water, as the salt water will immediately settle towards the bottom (being heavier), and allow the freshest water to be nearest to the salt. In this way, the salt may be all dissolved, and thus make the brine used to slake the lime. It may be necessary to apply the brine at intervals of a day or two, and to stir the mass often, as the amount of water is too great to be readily absorbed.
This mixture should be made under cover, as, if exposed, it would obtain moisture from rain or dew, which would prevent the use of all the brine.Another objection to its exposure to the weather is its great liability to be washed away by rains. It should be at least ten days old before being used, and would probably be improved by an age of three or four months, as the chemical changes it undergoes will require some time to be completed.
Explain the character of this mixture as represented in the diagram. (Black board.)
Explain the character of this mixture as represented in the diagram. (Black board.)
The character of this mixture may be best described by the following diagram:—
We have originally—
The lime unites with the chlorine of the salt and formschloride of lime.
The sodium, after being freed from the chlorine, unites with the oxygen of the air and forms soda,which, combining with the carbonic acid of the atmosphere, forms carbonate of soda.
Chloride of lime and carbonate of soda are better agents in the decomposition of muck than pure salt and lime; and, as these compounds are the result of the mixture, much benefit ensues from the operation.
Whenshelllime cannot be obtained, Thomaston, or any other very pure lime, will answer, though care must be taken that it do not contain much magnesia.