VIII. TILLAGE OPERATIONS (cont.)
When, by such operations as have now been described, land has been reclaimed from its natural state, and rendered fit for the purpose of the husbandman, it is everywhere so charged with the germs of weeds, most of which possess in a remarkable degree the power of reproduction and multiplication, that it is only by the most incessant and vigorous effort he can restrain them from encroaching upon his cultivated crops, and regaining entire possession of the soil. He can do much towards this by ordinary tillage, and by sowing his crops in rows, and hoeing in the intervals during the early stages of their growth. But if his efforts are restricted to such measures only, the battle will soon go against him. Besides this, all arable soils in which clay predominates, particularly when undrained, have such a determined tendency to become compact and soured, that under ordinary efforts they fail to yield a genial seed-bed. There is a necessity, therefore, for having recourse, from time to time, to that ameliorating process of lengthened tillage called fallowing. This process begins in autumn, immediately after the removal from the ground of the cereal crop, which had been sown upon the land newly broken up from clover lea or natural sward, and extends either to the time for sowing turnips and analogous crops in the following spring, or is continued during the entire summer in preparation for autumn-sown wheat. We shall first described the modification of the fallowing process by which the soil is prepared for the sowing of drilled green crops, and then the more prolonged form of it usually called summer or naked fallow.
Green Crop Fallow
The object aimed at being the thorough disintegration and cleaning of the soil, the usual practice is to begin by ploughing as deeply as is found practicable. This first or autumn furrows is accordingly turned over to a depth of 8or 9 inches; or by using a stronger plough drawn by three or four horses, it is carried to 12 inches in depth; and in some cases, by following with a subsoil plough in the wake of the common one, the soil is stirred to the depth of 14 or 16 inches. All cultivators are agreed as to the importance of thus deeply and effectually disintegrating all soils that are naturally dry or thoroughly drained. In the case of the undrained lands, and even of very unctuous clays, although well drained, such deep stirring of the soil in autumn does but increase its capacity of retaining the rains of winter, and of being thereby more effectually soured, and is therefore to be avoided. Assuming, however, that we have to do with soil thoroughly drained and moderately friable, it is undoubtedly beneficial to loosen it deeply and thoroughly at this stage. But before this deep ploughing is set about, it will be worth while to consider well its bearing upon the cleaning part of the process. On carefully examining the fields at the time of reaping the grain-crops, and from week to week thereafter, the roots of the couch grass are found at first lying close to the surface; but instantly, on their getting the ground to themselves, they begin to send out fresh fibers, and to pus their shoots deeply into the soil. In these circumstances, to proceed at once, according to the customary practice, to plough deeply, allows these weeds much time to increase, while this laborious and tedious operation is going on; and although, when performed, it gives some present check to their progress, by burying them under a mass of loosened soil, it not only increases the difficulty of their after removal, but places them out of the reach of frost, and in the best possible position for pervading the entire soil, on the first recurrence of mild weather. The consequence is, that fallows so treated are invariably found in spring more fully stocked with quickness than they were at the time of the autumn ploughing. The observation of this suggested the practice, now very common in England, of cleaning fallows in autumn before giving the first deep furrow. For this purpose, such implements as Biddles scarifier, the broad-share paring-ploughs, or better still, the common plough, divested of its mould-board and fitted with a share a foot broad, are set to work as fast as the grain-crops are reaped, and the whole surface is rapidly pared at a depth of three or four inches. This completely loosens the yet shallow lying roots of the couch-grass, which are then freed from the adhering earth by the Norwegian and chain-harrow, raked together and burned, or carted off. This pulverizing of the surface soil in early autumn is usually followed by the springing up of an abundant crop of annual weeds and of shaken grain, which are thus got rid of by the subsequent ploughing. So great and manifold are the advantages of this modern practice, that in those districts where it is most in use, other autumn work, even wheat sowing, is comparatively neglected until it is accomplished. When the weeds have been got rid of in this summary and inexpensive manner, deep ploughing is then resorted to with unalloyed benefit. Whenever steam-power becomes fully available for tillage operations, this autumn cleaning and deep stirring of fallows will be accomplished rapidly and effectually, and the teams will meanwhile be set at liberty for root-storing, wheat-sowing, and other needful work, which can be well done only when accomplished during the brief season of good weather, which usually intervenes betwixt the close of harvest and beginning of winter.
In the case of farms that have for a lengthened period been carefully cultivated, the stubble may be found so clean as not to require the whole area to be scarified in the manner now described. Instead of this, it may suffice to have the ground carefully examined, and such patches or stray plants of couch-grass, or other perennial weeds, as are met with, forked out. By this means the fallows are kept clean at little expense, and when spring arrives, those repeated ploughings, and other tedious and costly operations, are wholly avoided, in performing which the condition of the soil is marred and the best seed-time often missed. When fallows are thus cleaned in autumn, it is highly advantageous to cart on to them at once, and cover in with a deep furrow, all the farm-yard dung that is on hand up to the completion of their first ploughing. From the length of time which must elapse before the land can again be touched, it is quite safe, or rather it is highly advantageous, to apply all the recently made dung, although in a very rough state. In doing this, it is necessary that a person precede each plough, and trim the rank litter into the previous furrow, that it may be properly covered up and regularly distributed. Unless this precaution is observed, the ploughs are constantly choked and impeded, the manure is drawn together into unsightly hassocks, and the whole operation is imperfectly performed. The recommendations to this practice are --- First, an important saving of labour; for the manure being carted direct from the yards, &c., on the land, and evenly spread over it, there is no forming, covering up, and turning of dunghills, or refilling and carting in spring. This heavy work is accomplished at a season when time is less pressing than in spring, and the sowing of the crop can be proceeded with more rapidly when the time for it arrives, and while weather favours. Second, there is a saving of manure by burying it at once in its rough state, instead of first fermenting it in large heaps; and a large portion of the fallow-break can thus be dressed with home-made manure. Third, the rough dung thus ploughed in decomposes slowly its virtues are absorbed and retained by the soil, with the whole mass of which it is thoroughly incorporated by the spring tillage, and which, in consequence, is found, after such treatment, in a peculiarly mellow and favorable condition for receiving the seed.
The advantages of autumn cleaning and manuring of land in preparation for green crops are so great that the utmost exertions should be made to secure them. Over a large portion of England the harvest is usually so early as to leave ample time for accomplishing the cleaning process before being arrested by bad weather. From the later harvest season and more humid climate of Scotland, it is there more difficult to carry it out the whole extent of the fallow-break; but still, with promptitude and energy, much can be done. One of her shrewd and intelligent sons, Mr. Tennant, the inventor of the grubber which bears his name, has, however, introduced a system of autumn tillage, found upon the same principle, and accomplishing virtually the same end, but less expensive and better adapted to the climate of Scotland than that just described. So soon as the grain crops are harvested, Mr. Tennant sets his light grubbers going, and by working them over the whole field several times and in opposite directions, stirs the whole surface soil to the depth of six or eight inches, tears up and brings to the surface all root-weeds, where, after being knocked about and freed from adhering soil by repeated harrowing and a final grubbing, they are left for the winter. In our own practice we have latterly improved, as we imagine, on Mr. Tennants plan by broadsharing the land before using the grubbers, and also by employing the Norwegian harrow instead of the common one. The broadsharing ensures that the whole of the couch-grass and other weeds are thoroughly loosened without being buried, and the Norwegian harrow shakes out the roots from the adhering earth better than the common harrow. When it is intended to treat a field in this way, care should be taken at harvest time to reap the crop as close to the ground as possible, as rank stubble seriously encumbers the tillage implements. In setting about the grubbing of a field it is expedient also to begin with the headlands, and to work them thoroughly all round twice over, before they are trodden down by the frequent turning of the horses upon them. If this is omitted it will be found nearly impossible to have the margins of the field as well cultivated as the rest of it. A field thus treated presents for a time a singularly untidy and uncompromising appearance; but the ultimate effects of the practice, as well in the cleaning as the disintegrating of the soil, are very remarkable. When roots of couch-grass, &c., are freed from the soil, and fully exposed to the vicissitudes of the weather at a season when their vital force is at the lowest point, they are unable to resist its effects, and gradually die. If placed in similar circumstances in spring, with their vital energy in full play, the merest point of a root embedded in, or even in contact with, pulverized soil, enables them to push down fresh fibers, to re-establish their connection with the soil, and to grow as lustily as ever. But so completely is the destruction of these pests secured by this simple process of winter exposure, that on the return of spring they may be ploughed in with impunity. Mr. Tennant assures us, that ever since he adopted this practice he has been enabled to dispense with the removal of these weeds. Having had an opportunity of inspecting his farm, we are enabled to testify to its cleanliness and high state of fertility. On this plan, then, the cleaning of fallows is accomplished by tillage operations alone, without any outlay for taking or hand-picking, burning, or carting off. Nor is this done at the expense of the pulverizing part of the process. On the contrary, Mr. Tennant asserts, and we have so far verified his assertion by actual experiments, that by disintegrating the soil in autumn, as is done by this broadsharing, grubbing, and harrowing, it receives far more benefit from the alternation of frost and thaw, rain and drought, than when merely ploughed and left lying during winter in compact furrow-slices. This plan affords the same facilities as the other for autumn manuring, if the weeds are raked off at once from so much of the fallow-break as it is wished to manure before winter. When the remainder is ploughed in April following, more of it may then have the farm-yard dung applied to it in the same way. Agriculturists owe a large debt of gratitude to Mr. tenant for the invention of his beautifully simple and efficient grubber, and for the scientific application of it to the fallowing process. Those who have been pursuing this system of tillage will be much interested in observing that it has been adopted by Mr. Smith of Woolston, who is carrying it out to perfection by means of his steam-drawn implements.
The autumn tillage of the fallows having been accomplished in one or other of the ways described, the land is left untouched till the return of spring. If it is infested by annual weeds, it is expedient, as soon as it is dry enough to bear treading with impunity, to level and stir the surface by a turn of the harrows. This slight moving of the mellowed surface-soil induces the seeds of weeds to germinate more quickly than they would otherwise do, and thus a crop of them is got rod of by the next tilling. This preliminary harrowing is useful also in affording a level course for the tillage implements. By the time that the labour connected with the sowing of spring crops is over, the fallows are usually dry enough to be stirred with safety. This point must, however, be well seen to, as irreparable mischief is often done by going upon them too soon. And now it is, that, instead of rigidly following any customary routine of so many ploughings, harrowings, and rollings, the skilful cultivator will regulate his procedure by the actual circumstances of his soil, and the object which he has in view. What is needed for the successful growth of drilled green crops is to have the soil free from weeds, thoroughly disintegrated to the depth of six or eight inches, and yet moist enough to ensure the ready germination of seeds deposited in it. Where such autumn cleaning and manuring as we have described have been successfully carried out, all that is needed, in order to obtain a proper tilth, is to go to work with light grubbers, first in the line of the previous furrows and then across them, and then to harrow, roll, and remove any weeds that have been missed in autumn, after which the soil will be in the best possible condition for drilling. On friable soils, this method of performing the spring tillage by means of the grubber instead of the plough is perfectly practicable, and has manifold advantages to recommend it. The saving of labour is very great, as a man and pair of horses will more easily grub four acres than plough one acre. Weeds are more easily removed, as the grubber pulls them out unbroken, whereas the plough cuts them in pieces. The soil that has been all winter subjected to the mellowing influences of the weather, and which, in consequences, is in the best possible condition to yield a genial seed-bed, is retained a-top, whereas ploughing buries it and brings up clods in its stead. And, lastly, the soil being merely stirred, without having its surface reversed, its natural moisture (or winter sap) is retained, whereby the germinating seeds sown in it become almost a certainty. The importance of this last point in the cultivation of such crops as the turnip, whose seeds must usually be sown during hot and dry weather, can scarcely be overrated. This practice is peculiarly appropriate for soils of loose texture, which are invariably injured by repeated ploughings. But it is also resorted to successfully on soils of the opposite extreme. Many farmers in the Lothians now grow abundant and extensive crops of turnips on strong clay soil by spreading a liberal dressing of dung on the stubble in autumn, ploughing it in with a deep furrow, leaving the land untouched until sowing-time has fully arrived, and then stirring the mellowed surface soil by the grubbers, removing weeds, and drilling and sowing at once without any ploughing. When this system is adopted on tenacious soils, it is prudent to operate upon portions of the field in detail, taking in only so much at a time as can be grubbed and drilled the same day; for if rain should intervene betwixt the grubbing and the drilling, the soil would set like mortar and the tide be lost. When once the ridgelets are made up in good condition, they can withstand a fall of rain with comparative impunity; and hence the occurrence of a course of fine weather, when the season is yet too early for sowing, is sometimes taken advantage of by preparing the land and making it up into ridgelets, although it should require to remain in this state weeks, or even months, before sowing takes place. In such a case, immediately before sowing, the ridgelets are first partially leveled by harrowing length-wise, in order to loosen the soil and destroy annual weeds, and then again made up by using a double-breasted plough. We must here, however, insist upon the importance of having the grubbing thoroughly performed, which it cannot be unless the tines penetrate the soil as deeply as the plough has done at the autumn ploughing. It is owing to the neglect of this that the system has failed in the hands of many farmers, who first mismanage the operation and then throw the blame upon the grubbers. To ensure success, the implement must be set so as to work at its full depth, sufficient motive power being applied by yoking three horses, if necessary, to each grubber at the first and also at the second going over, and there must be vigilant superintendence exercised lest the ploughman do the work slightly. It is sometimes objected to this system of spring tillage that it fails to rid the land of thistles and other tap-rooted weeds; but it is surely easier to fork these out as they appear, than to plough a whole field merely to destroy as many thistles as a man, it may be, would dig up in a day. By taking advantage of the tilth obtained by the action of the elements, instead of first ploughing down the mellowed surface, and then attempting laboriously to reduce the obdurate furrows by mechanical means, skilful and energetic farmers now succeed in preparing even tenacious soils for drilled green-crops, at little expense, and with a good measure of certainty.
On these opposite classes of soils, then --- the very loose, and the tenacious --- spring tillage, in preparation for root-crops, is performed to better purpose by means of the grubber than the plough. Betwixt these extremes, however, lies the most valuable class of soils --- the strong fertile loams --- on which the heaviest crops and best quality of Swedes are grown. With these it is usually expedient to have recourse to at least one spring ploughing, as soon, but only as soon, as the soil is dry enough to crumble freely to the very bottom of the furrow. As this usually occurs from four to six weeks before the time of sowing the crop, it is advisable to plough the entire field, and leave it so until rain falls, when a moderate use of the grubber, harrows, and light roller, usually suffices to produce a good tilth for ridging. When operations are not thus facilitated by a seasonable fall of rain, it is necessary to proceed somewhat differently. The field is lying as it was left by the plough, with a rough dried surface. If harrowed while in this state, an abundant crop of clods is brought to the surface, which quickly harden when thus fully exposed to drought. To avoid this inconvenience, the field is first rolled with a heavy roller, and then grubbed across the direction in which it was last ploughed. By this means the clods, being partially crushed and pressed down amongst the loose earth, resist the grubber, and are crumbled by it, instead of being merely raked out and left entire on the surface, as would happen but for this preliminary rolling. The grubbers are followed closely by harrows and a light roller, and these again by the grubber; but this time with seven tines on instead of five, after which a sufficient tilth is usually obtained. All this is on the supposition that the land is clean when these spring operations are commenced; for should it be otherwise, it is usually better to begin with the grubber on the stale winter furrow, and to get rid of the weeds, before using the plough. If it is found necessary to plough near to the time of sowing, then the harrow and roller must keep pace with the ploughs in order to retain moisture and prevent the formation of clods. The Norwegian harrow is the proper implement to use in such cases. Let it ever be born in mind that if the soil is cleaned and sufficiently disintegrated, the less working it gets at this stage the better.
It may be well indeed to remind the reader that although the fallowing process can most conveniently be gone about during the period which intervenes betwixt the removal of a grin-crop from the ground and the sowing of the succeeding root-crop, and on this account is often spoken of in a loose way as being performed " in preparation for the root crop," it is fallacy to regard this laborious and costly process of tillage and cleaning as undertaken solely or mainly for the benefit of the turnip or other root-crop, then about to be sown. The other crops of the rotation benefit by it in a far greater degree, and it would be required on their account although turnips were not grown at all, as may be seen in the case of clay lands with their periodic naked fallows. It is the overlooking of this fact which has led people to charge the whole cost of this fallowing process, and of all the manure then applied to the land, against the turnip-crop, and then to represent this crop as the most costly one which the farmer grows, --- one which often yields him less than it cost to produce it. Undoubtedly the cost of the fallow must be charged equally against all the crops of the rotation.
Summer or Naked Fallow
Having thus described at length that modification of the fallowing process by which the soil is prepared for the sowing of green crops, we shall now, as proposed, speak of that prolonged form of it called a summer or naked fallow. From the facilities now afforded, by means of tile-draining and portable manures, for an extended culture of green crops, this laborious and costly process, which in its day was justly regarded as the very key to good and profitable farming, is now restricted to the more obdurate clay soils, or to cases where draining and other modern improvements are neglected. The manifold advantages of having abundant crops of turnips, or mangel-wurzel, instead of naked fallow, sometimes tempt the occupiers of clay soils to push the cultivation of these crops beyond due bounds. We know of cases where, after large expenditure in draining, the cultivation of turnips has been carried to such an extent, and conducted so injudiciously, that the land has got foul and soured, and its gross produce has been reduced below what it was while the land was undrained, and under a regular system of all but exclusive naked fallows. However thoroughly drained, clay soils retain their ticklish temper, and are so easily disconcerted by interference during unfavourable weather, that the preparing of them for the cultivation of root-crops, and still more the removing of these crops when grown, is at best a hazardous business, and requires to be conducted with peculiar tact. Judicious farmers, who knows by experience the difficulties that have to be overcome in cultivating such soils, are of opinion that all that can yet be ventured upon with safety is to prolong the period of the naked fallows recurrence, rather than entirely to dispense with it. After a series of alternate grain and cattle crops, it is accordingly still their practice to wind up with a summer fallow, by which they rectify unavoidable defects in the tillage of preceding years, and put their land in good humour for entering again upon a fresh course of cropping.
This process is begun by a deep ploughing in autumn, in performing which the land is gathered into ridges, that it may kept as dry as possible during winter. When the more urgent labours of the following spring are so far disposed of as afford leisure for it, a second ploughing is given to the fallow, usually by reversing the furrows of autumn. This is followed at intervals by two cross-ploughings, which are made to reverse each other, in order to keep the land level. As it is the nature of these soils to break into lumps, under the action of the plough, rather than to crumble down, the clods thus produced get so thoroughly parched in dry weather, that root-weeds enclosed in them are killed by sheer desiccation. To further this cheap mode of getting rid of them, the land is not rolled, but stirred by the grubber and harrow as frequently as possible, so as to expose the clods freely to the drought. We know by experience that fallows can be cleaned effectually by thus taking advantage of the tendency in clay soils to bake excessively under exposure to the hot dry weather which usually prevails in June and July. Should the season happen to be a showery one, this line of tactics must needs be abandoned, and recourse had to the judicious use of the grubber, Norwegian and common harrow, in order to free the weeds from the soil, and then clear them off by raking or hand-picking. This is more costly, and, as we believe, less beneficial to the soil than the simple method first noticed, which should therefore be attempted in the first place. As in hay-making, much can here be done in a few favourable days, by keeping grubbers and harrows at work, and turning the clods frequently. When farm-yard dung is to be applied to such fallows, it is desirable that it should be carted on and ploughed in before July expires. In applying it, two methods are followed. That usually adopted is, after marking off the ridges, to put down the dung in small heaps, at regular distances, and forthwith to spread it and plough it in. In the other, the land is formed into ridgelets, running diagonally across the intended line of the ridges, and the dung is enclosed in them in the manner to be hereafter described in treating of turnip culture. In either way, after the lapse of several weeks, the surface is leveled by harrowing, and the land is gathered into ridges by the last of this series of ploughings, hence called the seed-furrow. When lime is to be applied to such land, this is the stage of the rotation which is usually chosen for doing so. It is spread evenly over the surface, immediately before the last ploughing. In finishing off this fallowing process, it is necessary, on undrained lands, to be careful to clean out the ridge-furrows and cross-cuts, in anticipation of winter rains. But if such land is worth cultivating at all, it is surely worth draining, and this operation once thoroughly performed, puts an end to all further solicitude about furrows.
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