MANURES See also:

• ARM (a common Teutonic word; the Indo-European root is ar, to join or fit; cf. the Lat. armus, shoulder, and the plural word arma, weapons, Gr. apphs, joint, and the reduplicated apapilKSV, to join)

Chemical See also:

• ANALYSIS (Gr. avci and Meta, to break up into parts)

Without an adequate return to the land of the matters they are to be supplied. ~ removed in the produce, its fertility cannot be maintained for The atmosphere is the great storehouse of organic plant See also:

• FOOD
• FOOD (like the verb " to feed," from a Teutonic root, whence O. Eng. foda; cf. " fodder "; connected with Gr. lrareicOae, to feed)

See also:

• LAWES, HENRY (1595-1662)
• LAWES, SIR JOHN BENNET, BART

lo years, 1872-1881. 1882-1891. 1892-1901. 852-190I. Wheat 3 Unmanured continuously . . . . See also:

• BUSH

Bush. See also:

• BARLEY (Hordeum sativum)

1877-1906. Bush. Bush. Bush. Bush. Wheat 7 Unmanured ccntinuously : . . 17.4 14.5 10.8 14'2 116 Farm-yard manure yearly . . . . 26.7 27.8 24'0 26.2 Barley 7 Unmanured continuously . . . . 23.0 18.1 13'3 18' 1 I Ib Farm-yard manure yearly . 40'0 39'9 36.6 38.8 Whereas on the heavier and richer land of Rothamsted the produce of unmanured wheat has fallen in 58 years from 17.2 bushels to 12.3 bushels, on the lighter and poorer soil of Woburn it has fallen in 30 years from 17.4 bushels to 1o•8 bushels; barley has in 5o years at Rothamsted gone from 22.4 bushels to to bushels, whilst at Woburn (which is better suited for barley) it has fallen in 30 years from 23 bushels to 13.3 busltels.

At both Rothamsted and Woburn the application of farm-yard manure has kept the produce of wheat and barley practically up to what it was at the beginning, or even increased it. Similar conclusions can be See also:

• DRAWN

Of carbon, hydrogen and oxygen there is no lack, the atmosphere providing carbonic acid in abundance, and See also:

• RAIN (O.E. regn; the word is common to Teutonic languages, cf. Ger. Regen, Swed. and Dan. regn; it has been connected with Lat. rigare, to wet, Gr. 13pixeav)

The composition of the grain is likewise affected, becoming more nitrogenous. With crops, however, where rapid green growth is required, nitrogen effects the purpose well, though here, too, over-manuring with nitrogen will tend to produce rankness and coarseness of growth. Experiments at Rothamsted and elsewhere, as well as everyday practice of the farm, See also:

• BEAR
• BEAR, BLACK
• BEAR, BROWN
• BEAR, GRIZZLY
• BEAR, ISABELLINE
• BEAR, WHITE

Similarly, they are the constituents which are most readily removed in drainage, and hence the adequate supply of nitrogen for the plant's use is a See also:

• CONSTANT, BENJAMIN (1845-1902)

Phosphorus.—This is the most important mineral See also:

• ELEMENT (Lat. elementum)

Phosphoric acid occurs in the soil See also:

• BOUND, or BOUNDARY (from O. Fr. bonde, Med. Lat. bodena or butina, a frontier line)

Potassium.—The element third in importance, which requires to be supplied by manuring, is potassium, or, as it is generally ex-pressed, potash. This in its functions resembles phosphoric acid somewhat, being concerned rather with the mature development of the plant than with its actual increase of growth. Like phosphoric acid, potash is found concentrated throughout the plant in the early stages of its growth, but, unlike it, is in the case of a cereal crop all taken up by the time of full See also:

• BLOOM (from A.S. bloma, a flower)

On clovers and other leguminous crops it is highly benefcial, while on grass land it is of particular importance as inducing the spread of clovers and other leguminous herbage. This is well seen in the Rothamsted grass experiments, where with a mineral manure containing potash one-half of the herbage is leguminous in nature, whereas the same manure without potash gives only 15% of leguminous plants. Similarly, where nitrogen is used by itself and no potash given there are no leguminous plants at all to be found. Potash occurs in an ordinary fertile soil to the extent of about '20 %; a sandy soil will have less, a clay soil may have considerably more. Potash, however, is mostly bound up in the soil in the form of insoluble silicates, and these are often in a far from available form, but require cultivation, the use of lime and other means for getting them acted on by the air and moisture, and so liberating the potash. According to B. Dyer's method of ascertaining the availability of potash in soils, the amount of potash soluble in a I % citric acid solution should be about •005 %, otherwise the addition of potash manures will be a requisite. In the case of soils containing much lime a larger quantity would, no doubt, be needed. Potash, like phosphoric acid, is readily retained by soils, and so is not subject to any considerable losses by drainage. This retention is exercised by the ferric-oxide and alumina in soils, but still more so by the See also:

• DOUBLE
• DOUBLE (from the Mid. Eng. duble, the form which gives the present pronunciation, through the Old Er. duble, from Lat. duplus, twice as much)

Soda salts also, when in considerable excess, are able to liberate potash from its compounds, and to this is probably due, in many cases, the beneficial action attending the use of See also:

• COMMON

This acidity is also seen in the occurrence of the disease known as " See also:

• FINGER

6. Iron.—Iron is another essential ingredient of soil that is found in abundance and does not call for special application in manurial form. Iron is essential for the formation of chlorophyll in the leaves, and its presence is believed also to be beneficial for the development of colour in See also:

• FLOWERS, ARTIFICIAL

Sodium.—This is a widely distributed element. The influence of common salt (chloride of sodium) in liberating, when used in large excess, potash from the silicates in which it is combined in the soil has been already referred to, and in this way common salt and also nitrate of soda (the two forms in which soda salts are used as manures) may have some benefit. The principal purpose for which common salt, however, is used, is that of retaining moisture in the land. It is specially useful in a dry See also:

• SEASON (0. Fr. seson, seison, mod. saison, Lat. satio, sowing time, the spring, from serere, to sow; in Late Lat. the word is found with its present meaning, the spring being considered as particularly the season of the year)

ri. Manganese, &c.—Manganese occurs in minute quantities in most plants, and it, along with See also:

• LITHIUM [symbol Li, atomic weight 7•oo (0=16)]

So important were the functions of humus considered at one time that on this Thaer built his " humus theory," which was, in effect, that, if humus was supplied to the soil, plants required nothing more. This was based, however, on the erroneous belief that the carbon, of which the bulk of the plant consists, was derived from the humus of the soil, and not, as we now know it to be, from the carbonic acid of the atmosphere. This theory was in turn replaced by the " mineral theory " of Liebig, and then both of them by the " nitrogen theory " of Lawes and Gilbert. We pass next to See also:

• REVIEW (Fr. revue, from revoir, to see again, Lat. re and videre)

The composition of farm-yard manure will vary greatly according to the conditions under which it is produced. The principal determining factors are (I) the nature and See also:

• AGE (Fr. age, through late Lat. aetaticum, from aetas)

Straw is the most general litter used, but See also:

• PEAT (possibly connected with Med. Lat. petia, pecia, piece, ultimately of Celtic origin; cf. O. Celt. pet, O. Ir. pit, Welsh peth, portion)

Farm-yard manure, where the supply is limited, is mostly saved for the root-crop, which, however, generally needs a little super-phosphate to start it, as farm-yard manure is not sufficiently rich in this constituent. It serves a great purpose in retaining the needed moisture in the soil for the root crop. For potato-growing, for vegetables, and in See also:

• MARKET (Lat. mercatus, trade or place of trade)

In addition to nitrogen, some of these materials, e.g. See also:

• RAPE
• RAPE (from Lat. rapere, to seize)
• RAPE (Lat. rapum or rapa, turnip)

They are favourite materials with hop-growers and fruit-farmers, whose experience leads them to prefer a manure which supplies its nitrogen in organic form, and which acts continuously, if not too readily. It is the See also:

• CUSTOM (from O. Fr. costume, costume or coustume; Low Lat. costuma, a shortened form of consuetudo)

Hence it was made under as good conditions as possible; but, even then, the losses—after See also:

• DEDUCTION (from Lat. deducere, to take or lead from or out of, derive)

To prevent this loss, farmyard manure, as had been pointed out, should, whenever possible, be carted into the field, spread out at once, and ploughed in at the convenience of the farmer. It is, however, not always practicable to apply farm-yard manure just at the time it is made, and, as the manure heap cannot be altogether dispensed with, it is necessary to see how the manure may best be kept. The best dung is that made in regular pits or feeding-boxes. In them the urine is thoroughly absorbed, and, the manure being more compact through the constant treading, air enters less freely and the decomposition goes on less rapidly, the volatile matters, in consequence, not being so readily lost. See also:

• EXTERNAL

Dried Blood is another purely nitrogenous material, which how-ever seldom finds its way to the farmer, being used up eagerly by the artificial manure maker. It will contain from I2 to 14% of nitrogen. It is obtained by simply evaporating down the blood obtained from slaughter-houses. It is the most rapidly acting of the organic nitrogenous materials enumerated, and, when obtain-able, is a favourite manure with fruit-growers, being also used for root and vegetable growing. Soot is an See also:

• ARTICLE (from Lat. articulus, a joint)

Occasionally they are prepared with the addition of other fertilizing materials and made up as special manures. It may be taken for granted that sewage refuse by itself is not See also:

• WORTH
• WORTH, CHARLES FREDERICK (1825-1895)

Another theory puts it as the deposit from the saline residues of fresh-water streams. The crude deposit is termed caliche, and from this (which contains common salt and sulphates of soda, potash and lime) the nitrate is crystallized out and obtained as a salt containing 95 to 96% pure nitrate of soda. It is sold on a basis of 95% pure, and is but little subject to See also:

• ADULTERATION
• ADULTERATION (from Lat. adulterare, to defile or falsify)

One cwt. to the acre is a common dressing for corn crops, but for mangels it has been used to advantage up to 4 cwt. per acre. As a top-dressing for corn crops it differs little in its crop-results from its See also:

• RIVAL

See also:

• COPROLITES (from Gr. KInrpos, dung, and X10os, stone)

On grass-land its effect in increasing gramineous but reducing leguminous herbage is similar to that of nitrate of soda, but with corn crops it has not the same deteriorating influence on the quality of grain. It can be mixed quite well with superphosphate and other artificial manures, and is therefore a common form in which nitrogen is supplied in compound manures. It does not produce the bad effect on the tilth of certain soils that nitrate of soda does, but it is open to the objection that, if used continually on soil poor in lime, it will gradually exhaust the soil and leave it in an acid condition, so that the soil is unable to bear crops again until fertility is restored by the addition of lime. A usual dressing of sulphate of ammonia is i cwt. per acre. Calcium Cyanamide.—This is a new product which represents the earliest result of the utilization, in a commercial form, of atmospheric nitrogen as a manurial substance. It is obtained by passing nitrogen gas over the heated calcium See also:

• CARBIDE

In its action it should be very similar to nitrate of soda, with, possibly, some added benefit to certain soils by See also:

• REASON (Lat. ratio, through French raison)

But it is precipitated in a very See also:

• FINE

Basic slag is of various grades, containing 12 to 20% of phosphoric acid, which is believed to exist in the form of a tetracalcic phosphate. This phosphate is found to be readily attacked by a weak solution of citric acid, and this probably accounts for the See also:

• COMPARATIVE

It is usual to See also:

• BOIL

It is true guano, i.e. the deposit of sea birds, and was originally found on islands off the coast of Peru. Peruvian guano was first discovered in 1804 by A. von See also:

• HUMBOLDT, FRIEDRICH HEINRICH ALEXANDER, BARON
• HUMBOLDT, KARL WILHELM VON (1767-1835)

Guano contains much alkaline salts, and is, from its containing alike phosphates, nitrogen and potash in suitable forms and quantity, an exceedingly well balanced manure. In agriculture it is used for corn crops, and also for root crops, potatoes and hops. It is esteemed for barley, as tending to produce good quality. For vegetable and market-See also:

• GARDEN (from O. Fr. garden, mod. Fr. jardin; this, like our words " garth," a paddock attached to a building, and " yard," comes from a Teutonic word for an enclosure which appears in Gothic as gards and O. H. Ger. gart, cf. Dutch gaarde and Ger. .garten)

Such manures, the trade in which is a very large one, are variously known as " corn manure," " turnip manure," " grass manure " and the like, and much care is bestowed on their compounding and on their preparation in good condition to allow of their ready See also:

• DISTRIBUTION (Lat. distribuere, to deal out)

Salt.—The action of salt in liberating potash from the soil has been explained. As a manure it is sometimes used along with nitrate of soda as a top-dressing for corn crops, in the belief that it stiffens the straw. For root crops also, and mangels in particular, it is employed; also for cabbage and other vegetables. Limc.—The use of this is almost solely to be considered as a soil improvement, and not as that of a manure. Sulphate of lime (gypsum) is, however, occasionally used as a dressing for clover, and also for hops. The fact that superphosphate itself contains a considerable amount of sulphate of lime renders the special application of gypsum unnecessary, as a rule. As compared with natural " manures, like farm-yard manure, artificial manures have the disadvantage that they, unlike it, do not improve the physical condition of the soil. Artificial manures have, however, the advantage over farm-yard manure that they can supply in a small See also:

• COMPASS (Fr. corn pas, ultimately from Lat. cum, with, and passus, step)