The advantages of green manures consist mainly in the addition of organic matter which they make to the soil. The presence of this aids in the liberation of those mineral ingredients which are there locked up, and which, on being set free, act with so much advantage to the crop. The roots also exert a power in effecting this decomposition, beyond any other known agents, either of nature or art. Their minute fibers are brought into contact with the elements of the soil, and they act upon them with a force peculiar to themselves alone. Their agency is far more efficacious for this purpose than the intensest heat or strongest acids, persuading the elements to give up for their own use what is essential to their maturity and perfection. By substituting a crop for a naked fallow, we have all the fibers of the roots throughout the field, aiding the decomposition which is slowly going forward in every soil.

Clover and most broad-leaved plants draw largely for their sustenance from the air, especially when aided by the application of gypsum. By its long tap roots, clover also draws much from the subsoil; as all plants appropriate such saline substances as are necessary to their maturity, and which are brought to their roots in a state of solution by the up-welling moisture from beneath. This last is frequently a great source of improvement to the soil. The amount of carbon drawn from the air in the state of carbonic acid, and of ammonia and nitric acid, under favorable circumstances of soil and crop, is very great; and when buried beneath the surface, all are saved and yield their fertility to the land; while such vegetation as decays on the surface loses much of its value by evaporation and drainage. In the green state, fermentation. is rapid, and by resolving the matter of plants into their elements, it fits the ground at once for a succeeding crop.

The following from the Hon. Daniel Lee, editor of the Southern Cultivator, is commended to the attention of Southern farmers:

"The first thing I did when I came to Georgia, a year and a half ago, and saw the extreme nakedness of the land, was to recommend the seeding with rye, at the last plowing in corn-fields, or soon after the crop ceases to grow, with a view to have this winter plant gather up from August till March whatever available atoms might be within reach of its roots and leaves. As the earth does not freeze, and heavy, washing rains fall in winter, 'the fat of the land' is largely consumed, and is either lost, like a burned candle, in the atmosphere, or carried like water from a dung-heap, into ditches and 'branches.' Barley, oats, and wheat all do well here, sown in November or December. It is now the 6th of February, 1849, and I have this day seen a field of oats which has been cut in part for soiling, for some weeks. Another, in barley, is so stout as to fall down or lodge. Winter pastures of rye are very valuable for stock of all kinds, although there are some clayey soils that the treading of cattle and sheep injures.

"Acting on my theory of keeping the earth always covered with some growing vegetation, Mr. M. B. Moore, of this city (Augusta), raised last season thirty-four and a half bushels of wheat from one of seed, which was harvested about the 20th May; then a crop of hay, equal to a ton and a half to the acre, which was mown in August; and then a crop

of pease, which was harvested in November-all from the same land. The land is now in wheat, to be harvested in May next, as before. There is no difficulty in growing three crops of small grain in a year at the South, if one is cut green for hay, as oats, pease, barley, and rye are often cut. To enrich the soil, I assume that the manure derived from both the grain and straw, or of the green crops, is all carefully saved and duly applied to the land. As about sixty per cent. of the hay and other food eaten by a cow, sheep, or horse is lost in vapor and carbonic acid, thrown out of the lungs in the process of breathing, and through the pores of the skin in insensible perspiration, one will increase organic matter in a poor soil much faster to plow-in clover, peas, timothy, and rye, than to feed these to domestic animals, and apply all their excretions to the land."

The following table from Boussingault gives a comprehensive view of the proportion of azote or nitrogen contained in the most common manures, and of their quality and equivalents, as compared with farmyard dung. Thus ten pounds of fresh cotton-seed oil-cake are equal in value to one hundred fresh or wet farm-yard dung, as far as the nitrogen in each is concerned. To form a perfect table of equivalents, the phosphates, potash, etc., must be also taken into consideration.

Night Soil is a very valuable fertilizer. It should be composted with powdered charcoal, peat, or plaster. When charcoal is freely used, this substance becomes entirely inodorous, and an offensive nuisance is thus converted into a valuable application to any crop.

Guano is the substance of the manure of birds with the water evaporated. The Peruvian and Bolivian are the best varieties, and when these can be bought pure, delivered at not over three dollars to three dollars and a half per hundred weight, it is generally the cheapest manure to be obtained, as it is so easily applied-the labor of applying other manures often approaching the price of guano. It is well to apply about two hundred weight per acre, with one-half the usual quantity of other manure. Guano should never in a fresh state come in contact with seeds or the roots of plants, as it is sure to destroy their vitality. In setting out fruit-trees and shrubs of all kinds, guano is the cheapest and most convenient manure to apply. After the holes are dug, sprinkle the bottom thinly with a handful of guano. Cover this at least three inches deep. On this you may plant your trees with safety, and after the roots are covered, a little more may be sprinkled, and the whole covered with soil. But the great value of guano is in forming liquid manure; one pound of guano to five gallons of water, applied once a week, will add wonderfully to the growth of any plants watered with this mixture. For very delicate plants, twice the above quantity of water should be given. If guano is not to be had, the manure of fowls is a good substitute. This liquid is especially valuable in the flower-garden. It must be poured upon the roots, and not upon the leaves or collars of the plants. On lawns, a pound sprinkled upon each square rod will restore their verdure. A great advantage of applying guano is that no seeds of weeds are scattered in the soil.*

Bones are an especially useful application to almost any crop. Bones contain sixty-six parts of earthy matter, mostly phosphate of lime, and thirty-four parts of gelatine. Phosphate of lime, next to ammonia, is the most necessary application to a soil, because it is the first element exhausted. Gelatine is rich in nitrogen, so that in bones are united the most valuable organic and inorganic manures. Applied whole, bones decompose too slowly to be of much value, and would be greatly in the way of tillage. They may be broken small, the fine dust sifted out, and the remainder moistened and thrown into heaps to ferment a few months. Bones can be dissolved by boiling in strong lye, and when dried by mixing with plaster, ashes, etc., may be applied broadcast or in drills. The best way to treat bones is to dissolve them in sulphuric acid, forming superphosphate of lime. A carboy of sulphuric acid, costing about four dollars, at wholesale, in the cities, and containing one hundred and sixty pounds, will dissolve about three hundred pounds of bones. The bones should be put in a tub. A portion of the acid, equal to one-third, should be diluted by pouring it into three times its bulk of water, and then should be poured upon the bones. After standing a day or two, pour on another portion of diluted acid, and if not already dissolved, in a day or two after the remainder should be added. The

* "Gardening for the South."

mass must be often stirred. The bones will dissolve into a kind of paste, which may be mixed with thirty times its bulk of water, and used as a liquid manure, but it is more convenient in practice to mix it with ashes, saw-dust, or fine charcoal. Three bushels of these dissolved bones are sufficient for an acre. The acid has converted the bones into a superphosphate of lime, which is very soluble, and is readily taken up by the plant. This is the most valuable of all manures for the turnip, and the quantity needed for the acre is so little that the expense is less than almost any other application.*

We close this article by the following pertinent extract from “The Farm:"

"All the urine, as well as all the solid excrements of animals, should be carefully preserved. It is very rich in nitrogen and the phosphates, and some writers on agriculture contend that its value, if properly preserved and applied, is greater than that of the dung. From an experiment made in Scotland it appears, that in five months each cow discharges urine, which, when absorbed by loam, furnishes manure enough, of the richest quality and most durable effects, for half an acre of ground. Think of this, ye American farmers, who are accustomed to allow so much of this richness to run to waste. The urine of three cows for one year is worth more than a ton of guano, which would cost from fifty to sixty dollars. Will you continue to waste urine and buy guano? Various methods of preserving and applying it will suggest themselves to the intelligent farmer. Stables may be so constructed that the liquid discharges of the cattle, together with the wash of the barn-yard, may be conducted to a tank or cistern, to be pumped out and applied directly to the land, or absorbed by saw-dust, turf, etc., and used in that form. If allowed to stand long in the tank, in a liquid form, fermentation is liable to take place, and the ammonia to pass off; but a few pounds of plaster of Paris occasionally thrown in will cause the formation of the sulphate of ammonia, which will not evaporate.

"But the waste of manures is not confined to those of the liquid form. The solid excrements of the animals are often left to drain, bleach, or ferment, till the greater portion of their most valuable elements have disappeared. Stable manures should be sheltered from the sun and rain, and fermenting heaps so covered with turf or loam as to prevent the escape of the fertilizing gases. Plaster, as in the case of urine, will aid in retaining the ammonia. Boussingault, one of the most accurate of experimenters in agricultural chemistry, states, that while the nitogen in fresh horse-dung is two and seven-tenths per cent., that in the fermented and dried horse-dung is only one per cent. Horse-dung should be mixed at once with other manures, or with turf or loam, to retain its full value. The manure of sheep is strong and very active, and, next to that of the horse, is most liable to heat and decompose."

Gardening for the South."

III. ROTATION OF CROPS.

As different plants appropriate different substances, the rotation of crops has considerable influence in retaining and economizing the fertility of the soil. If the same kind of plants are continued upon the same soil, only a portion of the properties of the manure applied is used, while, by a judicious rotation, every thing in the soil, or in the manure, suitable for vegetable food, is taken up and appropriated by the crops. Some vegetables, as onions and carrots, are very exhausting to the soil, while lettuce is very slightly so. Hence, however plentiful manure may be, a succession of exhausting crops should not be grown in the same place, because abundance is no excuse for want of economy, and because manure freshly applied is not so immediately beneficial as those remains of organized matter, which, by long continuance in the soil, have become impalpably divided and diffused through its texture, of which each succeeding crop consumes a portion. Those plants generally are least exhausting which have the largest surface of leaves, not only because they are made up of a greater proportion of aqueous matter, but also because they are enabled to obtain more in proportion of their food from the atmosphere. A rotation was formerly thought necessary, from an idea that each plant throws off from its roots, into the soil, certain matters which are injurious to others of the same species afterward grown upon the soil, but this view can hardly be sustained. Another reason for rotation of crops is, that some crops are so favorable to weeds, that if continued long upon the same bed, the labor of cultivating them is much increased, while, if raised but once in a place and followed by a cleaning crop, the weeds are easily kept under.

Besides, many crops planted continually in the same soil are more liable to be attacked by the insects which are the peculiar enemies of those plants. Again, different plants derive their principal nourishment from different depths of soil. Hence, deep-rooted plants should be succeeded by those whose roots extend but little below the surface-perennial plants by annuals, crops left for seed, or that are of a dry, solid texture, by those which are succulent and juicy.*

The following view of the principles and the practice of rotation is from the pen of Mr. J. J. Thomas, one of the most practical and reliable agricultural writers of the age:

"In the arrangement of a rotation, no additional expenditure or labor is necessary; it costs no more to cultivate crops which are made to succeed each other judiciously, than to cultivate those arranged in the worst manner possible. The former may bring triple the successful results of the latter-not by the expenditure of five hundred extra days in drawing manure, or five hundred dollars' worth of ditching, but simply by making a proper use of one's brains.

"It seems surprising, under the circumstances, that so small a number seize the golden prize thus completely placed within their reachthat there are so few, even of those reckoned good farmers, who pursue any thing like a systematic succession, to say nothing of such a rotation

* "Gardening for the South."