For the American Agriculturist.
For the American Agriculturist.
Buffalo, October 25th, 1843.
Thereare four conditions that modify the value of a wheat crop. One may not only be larger in measure than another, but heavier for the same measure; yielding more flour from a given weight; and lastly, affording a greater proportion of gluten from the same quantity of flour. It is necessary for the farmer to have each of these considerations in view, if he would attain the utmost success in the cultivation of this invaluable grain. My object, in this brief article, will be, to afford some helps to the agriculturist in increasing the ultimate value of his crop. As a starting point, it will, perhaps, be most instructive to inquire, what are the constituent elements of wheat?
Sprengel has analyzed both grain and straw, and the following is the result:—1000 lbs. of wheat afford 11·77 lbs. and of wheat straw, 35·18 lbs. of ash, consisting of
Grain of wheat.Straw of wheat.lbs.lbs.Potash2·250·20Soda2·40·29Lime·962·40Magnesia·90·32Alumina with a trace of iron·26·90Silica4·0028·70Sulphuric acid·50·37Phosphoric acid·401·70Chlorine·100·30————11·7735·18
This analysis shows an amount of ash far below the average. Davy found 15·5 lbs. of ash in 100 lbs. of ripe wheat straw; and Johnstone, in one variety, grown on a soil abounding in limestone, 16·5 per cent. of ash.
Thus it will be seen, according to the above analysis of Sprengel, that of the total of grain, less than 1½ per cent., and of straw, rather more than 3½ per cent. is earthy or inorganic matter; while all the remainder is composed of the organic materials, carbon, oxygen, hydrogen, and nitrogen, of which carbon alone constitutes about one half. All these constituents are absolutely essential to the perfection of the crop. In the natural condition of a fertile soil when first reclaimed, these materials are usually found in sufficient abundance to produce wheat. Such was the condition of nearly all the land in New England, and the eastern portion of our own state; but a few years of careless, unscientific cropping, has exhausted one or more of those constituents which may have existed in an available form; and much of it, after a very few of the first years of its cultivation, has been of little or no value for wheat, under the system of tillage there adopted. It has been asserted by Dr. Dana, that in a soil purely granitic (and much of the land in that region partakes of this character), there is potash enough for successive crops of wheat for 3,000 years, and lime enough to last more than twice that period. But the result is the same for the growing vegetation, whether the materials do not exist at all, or are locked up beyond the reach of it. It is absolutely certain, if wheat will not grow with care and industry, and all the usual appliances of good husbandry, where it once nourished successfully, there is one or more ingredients wanted, in such a condition, that the plants can appropriate them to their own nourishment. And first of the inorganic matters.
The proportion of straw will vary from 2 to 3½ times the weight of the grain. Suppose the quantity taken off the land be estimated at 2½ times the weight of the grain. In a series of crops averaging 20 bushels of wheat per acre, for 30 years, we shall have as the result 36,000 lbs. of grain, and 90,000 lbs. of straw carried off the soil, charged with all the materials above enumerated, and probably sufficient to reduce the land to a very small capacity for production.
Some limited portions of the earth, as the plains of Babylon, when under skilful cultivation, the valleys of the Indus and the Nile, and the fields of Sicily, almost since the days of the flood, have produced luxuriantly, without the aid of manure to any extent; but it must be remembered the former have their fertility annually renewed by the rich overflowings of the rivers, which are charged with all the materials necessary to restore exhausted nature; while the soil of the last, being wholly of basaltic origin, is rich in the alkalies, which a year or two of rest, is sufficient to replenish in a soluble state, to be again taken up by the luxuriant crop. Hence, we have witnessed a drainage of nearly all the products from these fertile regions, for thousands of years, with impunity. But they are exceptions which only go to prove the general rule. The farmer must look to it, that all the ingredients that enter into his crops, are supplied by the materials in his soil, or a deficiency, or entire failure, will be the inevitable result.
Although all the constituents entering into the straw and grain, are absolutely essential to their perfection, they are not all equally essential to be contained in the soil. It is indispensable, however, that the earthy or inorganic portion of them be there, for these can not be obtained elsewhere. How shall they be best supplied? Ashes, it is believed, afford the cheapest, as well as one of the most effectual applications that can be made for grain. Of the ten fixed ingredients enumerated as entering into wheat, ashes yield potash, soda, lime, magnesia, sulphuric and phosphoric acids, in large proportions, and silica and iron in smaller. The chemical operation of the potash, and carbonate and sulphate of lime, however, when added to the soil, is to supply the silica, in a soluble state, from its natural condition, (it being found in abundance for this object in every soil, except in such as are formed almost exclusively of peat,) for the demands of the crop.
An increased supply of lime and gypsum, beyond what is found in the ashes, is frequently advantageous; and when the latter is beneficial, as it generally is, it should never be withheld to an extent in the highest degree useful. Of the operation of this last material, beyond yielding a portion of its sulphur to the gluten, we have as yet no satisfactory explanation. In respect tothe theory of its concentrating ammonia in the soil from the atmosphere, we have very contradictory authority. Liebig asserts it, Johnstone questions it, and Dana denies it; yet the increasing fertility its application produces, would seem to give the weight of experience in favor of Liebig's views.
The chlorine and soda, if not furnished by the ashes in proportions sufficiently large, may be procured by the application of common salt, which yields both. The phosphoric acid may be obtained in any required quantity, by the addition of bones, which, dry or calcined, yield both that acid and lime, phosphate of lime constituting 86 per cent. of bones. Most soils contain alumina in abundance to furnish the food requisite for wheat; yet as it is one of the most valuable soils for this grain, both as seizing upon and retaining ammonia, and furnishing a firm foothold for the roots of the plants, it is important that lands intended for this purpose, should be adequately supplied with alumina as a top-dressing, if naturally deficient in it.
We have, then, above, all the inorganic materials for the purpose required. But there is about 97 per cent. of the crop yet to be made up of the organic constituents, carbon, oxygen, nitrogen, and hydrogen. How shall they be provided for?
First, by the selection of a calcareous or clay soil, which will furnish a proper bed for the roots of the plant, and by their peculiar mechanical texture and chemical composition, will not only hold the manures incorporated with them, but also draw some of the requisite constituents largely from the air; the former absorbing carbonic acid, and the latter ammonia.
Second, by the liberal application of common farm-yard manure, to a crop preceding that of wheat, which will leave a rich mould highly conducive to an abundant yield of perfect grain. An instance has been recently given, of a Maryland farmer raising large successive crops of wheat, by the application of putrescent manure directly upon the grain, and all injurious effects were obviated by the use of a moderate quantity of lime. This is a practice, however, which has not been found generally to be successful, causing either blight, or such rapid and luxuriant growth, as to crinkle and lodge. This effect is also produced in peaty and rich alluvial soils, where the silicate of potash, so essential to the formation of a strong, upright stalk, is not furnished in a quantity large enough for the object.
Third, the liberal use of charcoal scattered through the soil. It is claimed from its use, that the wheat crop of France has been largely augmented within the few past years. Several instances of its greatly beneficial effects, have been noticed in this country; though its influence has not hitherto been felt on wheat, by an extensive Virginia planter, in two or three recent experiments. The great power of condensing gases peculiar to charcoal, was noticed by some of the early chemists. Murray mentions it, and Saussure gives a table of results, in which he shows that perfectly dry charcoal from boxwood, will absorb 90 volumes of ammonia; 85 of muriatic acid; 65 of sulphurous acid; 55 of sulphuretted hydrogen; 35 of carbonic acid, &c. This condensation takes place in its pores, and does not produce any alteration, or new chemical compounds of the gases thus stored up; but their use in an agricultural point of view, is invaluable; for while the coal yields no fertilizing matter from its own substance, being nearly indestructible, it takes from the atmosphere in great abundance, and hoards up for the future use of the plants, one of the most evanescent, as well as most useful materials for their perfection, viz., the nitrogen contained in the ammonia.
A fourth means for procuring a good yield of wheat, is by alternating with clover, and turning in a liberal share of it as a preparation for the wheat. This is practised extensively throughout the wheat districts of the United States, and has resulted in great benefit; for besides yielding a portion of food to the grain, it keeps the ground in the best possible mechanical condition.
A fifth means, is to return all the straw and chaff to the soil, as they contain a large quantity of the identical materials required for a succeeding crop.
With the foregoing causes in full action, and an adequate supply of moisture, whether from rains, dews, or artificial irrigation, the crop will draw largely from the atmosphere for the supply of its required organic constituents. Carbon will be furnished from its carbonic acid; nitrogen from its ammonia; hydrogen from its vapor, dews, and ammonia; and oxygen from air, water, and soil.
The use of all these materials,together with the selection of the best varieties of seed, will give the first three requisites of a wheat crop; large measure, heavy weight, and much flour.
Manures peculiarly adapted to the object, will tend in the highest degree to produce the greatest quantity ofgluten, the most valuable portion of the flour. It is true, that climate has much to do in condensing, and of course, improving the value of wheat. It is a general principle, that the warmer and drier the climate where it is grown, the more valuable the grain. Wheat from the south of Europe, is worth more than when grown in the north; and that from any portion of the United States, owing to our superior dryness of climate, is more nutritive than what is produced in Great Britain. This difference is increased from 8 to 14 per cent. in favor of the American. Gluten varies in wheat from 8 to 35 per cent.; in rye, 9 to 13; barley, 3 to 6; and oats 2 to 5. Thequalityof wheat with regard to the quantity of gluten it contains, is nicely estimated and fully regarded by accomplished bakers.
The nitrates of potash, or soda, are frequently used in England to increase not only the quantity, but especially the quality of their flour, a practice the high prices of land and produce may render profitable there, though it is hardly to be expected they could generally be used in this country to a profit. In an experiment lately tried in England, one acre of wheat dressed with one cwt. of nitrate of soda, gave 42½ bushels, weighing 60¾ lbs. per bushel; another acre dressed with two cwt. yielded 47-3/8 bushels, weighing 60½ lbs.; while an undressed acre, in every other respect similar to the others, yielded only 27-7/8 bushels, weighing 61 lbs.Numerous other instances could be given equally conclusive.
Although we may not be justified in using these somewhat expensive salts, so highly charged with nitrogen, there are sources of supply within our reach, especially rich in this material, and abounding in many of the other ingredients of fertility. These are animal manures of all kinds, but more particularly urine, human excrements, and the offal of animals, such as uncalcined bones, horns, hair, hides, flesh, blood, &c. All of these contain large proportions of nitrogen, and if carefully incorporated into the soil, would tend largely to the increased production and value of the wheat crops throughout the country. An experiment was made in manuring wheat with cow dung, which contains the smallest proportion of nitrogen, and this yielded 11·95 per cent. of gluten. Another parcel, grown on land manured with human urine, gave 35·1 per cent. Thus it will be seen, that the maximum of value in wheat, may be reached, by the application of an article, almost everywhere wasted in the United States.
It is by skilfully feeding the wheat plant with all the nourishment that it can take up, that the crops may be indefinitely increased. Lord Hardwicke stated, in a speech before the Royal Ag. Soc. of England, that the fine Suffolk wheat had produced 76 bushels per acre; and another and more improved variety had yielded the astonishing quantity, of 82 bushels per acre. There is no comparison between the capacity of an animal and seeds, to produce results; for while the former is limited to a definite growth, which no effort of science or skill can augment, a seed may multiply beyond almost any assignable limit. We have been shown a stool of wheat, originating from a single seed, the growth of the present season, with 30 stalks, averaging from 100 to 110 grains on each head. Over 3,000 perfect grains, is thus the product of a single parent in one season. It requires, then, but the proper pabulum to produce good wheat, within the wheat latitudes, in every portion of the Union. Some of our worn-out eastern lands may be so totally unsuited to its growth, as not to justify the efforts of reclaiming or fitting them for this object, especially, while we have a region in the west, every way adapted by nature, to its most successful cultivation. But we can not for a moment doubt, that when those western fields become comparatively full, industry and science will combine to clothe again those hills and valleys (now but partially robed with a scanty herbage), with teeming crops of wheat, such as gave to them, in their pristine days, a fame for fertility seldom exceeded.
R. L. Allen.