XII. CULTIVATED CROPS - ROOT CROPS (cont.)
The introduction of turnips as a field crop constitutes one of the most marked epochs in British agriculture. To the present day no better criterion exists by which to estimate its state in any district, or the skill of individual farmers, than the measure of success with which this or other root crops are cultivated. We have already, in our section upon fallowing, described in detail the process of preparing the soil for drilled green crops. Referring the reader to what is there said, we now proceed with our description of turnip culture.
Previous to the introduction of bone-dust and guano, farm-yard dung formed, in the majority of cases, the only available manure for the turnip crop. It was almost invariably formed into heaps in the field to which it was to be applied, and repeatedly turned, as great stress was laid on having it well rotted. The introduction of these invaluable portable manures has, however, not only immensely extended the culture of the turnip, but has materially modified the course of procedure. On the first introduction of bone-dust the practice was to use fold-yard dung as far as it would go, and to apply bone-dust alone, in quantities of from sixteen to twenty bushels per acre, to the remainder of the crop. Guano, too, for a time was used to some extent on the same principle; but now it is most satisfactorily proved that whereas very good crops of turnips can be obtained by manuring either with dung alone, at the rate of from fifteen to twenty tons per acre, or bones alone, at the rate of three or four cwt., much better crops can be obtained by applying to each acre its proportion of each of these kings and quantities of manures. A portion of the bones is now usually applied in the form of superphosphate of lime; and as this substance, and also guano, have a remarkable power of stimulating the growth of the turnip in its earliest stage, forcing it to the state fit for thinning from ten to fourteen days earlier than heretofore, there is now no occasion for the dung being in the advanced state of decomposition that was formerly found necessary. When farm-yard dung alone was used, it behoved to be in a soluble state, ready to furnish nourishment to the plant from the beginning. But in bringing it to that state a considerable loss is sustained by fermentation, and its bulk is so much reduced that it becomes difficult to distribute evenly the allowance which would be available for each acre, in order to give the whole crop a share of it. This, however, it is most desirable to do, as good farm-yard manure contains in itself the whole elements required by the crop; and hence an additional reason for the plans of applying farm-yard dung which have already been noticed. If that made during the previous summer has been applied in autumn to the lea before ploughing for oats, as far as it will go, and another portion of the contemplated turnip break dunged before the winter furrow, with all that has been made up to that time, and the future accumulations up to April formed into heaps, to be applied in the drills for the latest sowings, the manures produced on the farm may be made to go over nearly the whole breadth under root crops.
In proceeding to sow those portions that were dunged before the oat crop and on the stubble, all that is required is to form the drills, and apply the guano or bones, or mixture of both, by hand. In doing this, ten or twelve drills are set out the evening before, that all may be ready for a good start. The light manure is taken to the field in carts, which are unyoked at convenient distances for replenishing the aprons of the young persons (one for each plough) or the machine by which it is distributed along the drills. The sowers of the manure being started on the outside drills, the ploughmen proceed to open fresh ones inside in going, and to cover in the manure by reversing the first formed ridgelets as they return. The seed machine, sowing two rows at a time, follows close up to the ploughs, and thus the work goes rapidly on, each plough getting over from 2 _ to 3 acres a day. When farm-yard dung is applied at the time of sowing, the process is the same, except that the drills must be opened somewhat deeper, and that the dung-carts, one able-bodied labourer is required for each plough employed in drilling; and where these amount to three, six spreaders are required to distribute it evenly along the drills. In some districts the double-breasted plough is used in forming the drills and covering in the dung. In the hands of a skilful ploughman that implement does certainly make neater work to look at; but so far as the success of the crop is concerned, the common swing-plough is preferable, for in covering in with it the earth is made to run over the top of the ridgelet, by which means the clods fall into the hollow and the finest of the mould is left on the top, where the seed is to be deposited. With the double mould-board this cannot so well be done, and the consequence is, that a groove is formed on the top of the ridgelet, in which the small dry clods, carried up by the tail of the mould-board, are left, forming the worst possible bed for the seed. In parching weather it is usual to pass a light roller over the drills immediately after sowing, to retain the moisture and insure germination. The seed is deposited near the surface, half an inch of mould being a sufficient covering. The quantity sown is 2 lb per acre of globe or yellow turnip seeds, and 3 to 4 lb of Swedes. Care must be taken that the seed is fresh, so as to have a vigorous and thick plant. Thick sowing increases the difficulty of thinning out the plants, but it hastens their growth, and diminishes the risk of failure from the depredations of the turnip beetle. The time of sowing in the south of Scotland extends from the beginning to the end of May for Swedes, and thence to the middle of June for yellows and globes. A partial sowing of yellow or globe is, however, made by careful stock masters before sowing the Swedes, to be ready for use by the end of August or beginning of September, when pasturage fails. Sowings of early varieties, such as the stubble turnip and certain yellow kinds, are also made after winter tares or other catch crops, until the middle of July; but in Scotland they cannot be sown later than this with advantage, unless for the production of a crop of seed. The average weight per acre of Swedes may be stated oat 18 tons, and of turnips at 22 tons, but double these rates have occasionally been obtained. Recent experiments go to show that with liberal manuring and early sowing, the weight of the crop is considerably increased by thinning out the plants at wider intervals than has hitherto been customary. The usual practice in Scotland has been to sow in ridgelets 27 inches apart, with 9 or 10 inches betwixt the plants. Recent experiments establish the fact that, with 15 inches from plant to plant, much larger bulbs and a greater acreable produce are obtained. As it is ascertained that in the case of Swedes the largest bulbs are also the best in quality, it is of the greater consequence to allow them ample room.
The thinning is commenced as soon as the rough leaf is fairly developed. Previous to this operation the horse-hoe is worked betwixt the rows for the double purpose of destroying weeds and facilitating the operation of thinning. This operation is sometimes still farther facilitated by using Huckvales machine, which slaps out the rows so as to leave tufts of plants at regular distances apart. The singling of the plants is performed by the hand-hoe. The young persons by whom this work is usually performed advance in echelon with their backs to the untouched work, the steadiest and most expert worker leading the band. This arrangement insures a uniform rate of progress, saves the finished work from being trodden upon, and keeps the workers closely under the eye of the steward. This thinning of the rows, so as to leave single plants at regular intervals of 12 to 15 inches apart, is accomplished by an alternate thrusting and drawing motion of the hoe, which a little practice enables the workers to perform with such precision that very rarely do they either make a gap or to stoop down to disentangle them with their fingers. Three of these workers can usually thin an acre in a day. With ordinary care on the part of the overseer, there is no great difficulty in getting the plants left single at proper intervals; but it is very difficult to get the hoers trained to select and leave only the stoutest plants. And yet so important is this, that, all other things being equal, a difference of two to three tons per acre in the rate of produce has been ascertained to result on comparing rows that had been thinned by a person who took pains to select and leave the best plants, with others on which they had been left indiscriminately. When the plants have rallied after the thinning, and begun to grow rapidly, the usual practice has been to turn a furrow from either side of them into the middle of the interval by a one-horse plough, and then to level this down by a turn of the horse-hoe. A great improvement on this practice is to use Tennants grubber instead, adjusted for drill work in the manner already described. By thus using a strong implement drawn by two horses, the soil in the intervals betwixt the rows can be stirred a foot deep if required, without any risk of hurting the young plants, and this, too, is accomplished by a single operation. A second hand-hoeing is then given, which usually completes the after culture.
The nature of the soil will generally determine the mode of consuming the crop. On all loose, dry soils, feeding off by sheep is the most profitable plan; whereas on deep, strong loams, it is advisable to withdraw the whole produce, and have it eaten by cattle, as, unless in very favourable weather, when even a fourth is fed off by sheep, the extra manuring does not compensate to the after crops for the injury which they usually sustain from the treading and poaching. On the poorest class of light soils the whole crop should, if possible, be consumed where it grows by sheep; but on those of a better description, a third, a half, or two-thirds may be withdrawn for the feeding of cattle, according to circumstances. Whatever the proportion left on the ground, care is to be taken to regulate the intervals so as to distribute the treading and droppings of the sheep as equally as possible over the field.
The management of the turnip crop so as that it may be supplied to the live stock in the best possible condition during the entire season, is a point of the greatest importance. The portion that is to be used as cattle food is removed from the ground as soon as the crop is sufficiently matured, and before the time when drenching rains and severe frosts may ordinarily be looked for. The best way of preserving turnips is by storing in broad flat heaps, not exceeding 20 inches deep, on some dry and sheltered situation, open to the sun, and covering them with a good coating of straw. It takes less labour to put them together in this way, and less straw to cover them; and being less exposed to frost and parching winds, they retain their juices much better than when stored in long narrow heaps. The pulling of Swedes preparatory to storing is much facilitated by passing under them a sharp share, and so cutting across the tap-roots without displacing the bulbs. The thatch of the corn-stacks that are thrashed in autumn is usually reserved for covering turnip heaps. After 1st November it is well to make diligent use of every favourable hour in thus securing the turnip crop.
The portion to be fed off by sheep must necessarily be treated in a different manner. What is to be used after Christmas can be very readily defended against frost by earthing up in the drills with the common plough. But as what is to be consumed by the young sheep must be pulled and trimmed at any rate, in order to be sliced, the best way is to throw the turnips into heaps at regular distances, and cover them with a thin coating of earth. By this means the turnips are kept from running to stems, and the sheep gets them clean and fresh, whatever the state of the weather. [Footnote 367-1] The same end is secured by opening a trench by a bout of the common plough, into which the turnips from two drills on either side are laid in regular order with their tops uppermost, and the earth turned over upon them by reversing the course of the plough. When wanted for use they are again unearthed by means of the plough. The feeding qualities of turnips are so seriously impaired by exposure to frost, even when they escape actual destruction, that the expense of securing them by one or other of these methods is always amply repaid. In very mild winters, again, storing is equally effective in preventing the virtues both of the turnips and the soil from being wasted by the pushing of the seed stems.
The turnip is liable in the early stages of its growth to the attacks of various insects. The most formidable of these enemies is the turnip beetle, which ffrequently settles upon the plants as soon as they appear above ground in such numbers as totally to destroy the whole of them. The best way of guarding against these nimble adversaries is to endeavour, by careful preparation of the soil, liberal manuring, and thick seeding, to secure a thick plant and rapid growth; for whenever the rough leaf is expanded the risk from this quarter is over. From time to time the young turnip plants are assailed by the larvae of certain butterflies and moths, which sometimes appear in such numbers as to cause serious alarm, but ordinarily their attacks occasion but a slight check to growth of the crop.
A far more formidable evil is the disease called "fingers and toes," which, although long known, seems to be steadily extending, and has been wider spread and more virulent since 1851 than in previous years. This truly formidable disease sometimes shows itself by the time that the plants are ready for thinning, but more usually it is about the stage when the second hoeing is given that unmistakable indications of its presence are observe. The crop appears in high health, and is making rapid growth, when suddenly, under hot sunshine, numbers of the plants are seen to droop with flaccid leaves; and examination being made, it is found that the disease has already made serious progress. In some cases it is chiefly confined to the tap-root, which is distorted with knobby excrescences. In others, the roots present a thickened, palmated appearance, giving rise to the popular name for the disease, "fingers and toes;" while in others the lateral roots expand into glandular-looking tubers, which frequently appear partially above ground at distances of several inches from the central stem. For a time all these forms of the excrescences present a smooth healthy looking skin, yielding no trace of the presence of insects of any king, either externally or internally. By-and-by the skin cracks over the excrescences, which speedily assume a gangrenous appearance. Indeed, the whole symptoms present a striking analogy to cancer in the animal system. By the time that the healthy plants are approaching near to maturity, the most diseased ones have usually lost all resemblance to turnips, and there remains on the land a substance like rotten fungus. In very bad cases whole acres together are found in this state, with here and there a sickly distorted turnip still showing a few green leaves. At other times a few only of the plants are wholly destroyed; the field, to a casual observer, looking not much amiss, though a closer inspection proves that the general crop is of stunted growth, with few plants entirely free from the disease. Such partially disease roots are not absolutely rejected by sheep, but they are evidently unpalatable and innutritious, while the crop as a whole is more speedily consumed than its general appearance would lead one to expect. When this disease appears on farms that have previously been exempt from it, it is usually confined for a year or two to small patches, which, however, in the absence of remedial measures, steadily and rapidly extend, not only on the recurrence of a turnip crop on the same fields, but over the other parts of the farm. Indeed, there are not wanting indications of its being propagated by contagion; as, for instance, when tainted roots are carted into pastures, and the disease shows itself most in those places where they have been consumed, when, in course of rotation, the field comes afterwards to bear a turnip crop. When they are consumed by cattle in fold-yards, the dung may be the medium of contamination, on the supposition that this conjecture is well-founded. Ploughing land in a wet state evidently aggravates the disease. We know of one instance where a strip down the middle of a field was ploughed in autumn while soaked by rain, on which wet ploughed portion the turnips were evidently more diseased than over the rest of the field. In another instance which came under our personal observation, a ditch running along part of the top of a field of upwards of 50 acres, was scoured in spring, and the mud spread back over the headland. The whole field was, in the same season, sown with turnips, which proved and excellent crop, entirely free from "fingers and toes," with the exception of that portion of headland on which the mud was spread, where every plant was diseased. Although wholly in the dark as to the nature and propagation of this disease, it is well to know that the judicious application of lime is a certain remedy. In order, however, to its efficacy, it must be applied in a powdery state after the autumn ploughing, and immediately incorporated with the soil by harrowing; or else, as a compost with earth, spread on the lea before breaking up for oats. We know from experience that a very moderate dose (say four tons of unslaked shells o the acre) applied in this way will suffice to prevent thee disease. It is on light soils that its ravages are most frequently experienced, and to these heavy doses of lime are unsuitable. Indeed, whether for promoting the general fertility of soils, or for warding off the attacks of this disease, moderate applications of lime every twelve years or so seem preferable to heavier dressings at longer intervals. The name "fingers and toes" is not unfrequently applied to a distinct disease to which the turnip, in common with the cabbage and other coleworts, is liable-namely anbury or club root. When the knobby excrescence which is found on plants affected by anbury is broken up, it is found to encase a white maggot, whose presence is the obvious cause of the mischief. We have seen young cabbages which had begun to droop from clubbing, when pulled up, freed from the parasite, and replanted, regain healthy growth and come to prosperous maturity. In the case of the "finger and toe," the most careful investigation, aided by the microscope, has hitherto failed to detect any insect cause for this disastrous malady.
367 During the unusually wet winter of 1852-53 a large quantity of turnips and swedes intended for cattle food was stored in this way. The trimming and storing was carried on every dry day, and the carting postponed until the recurrence of frost or drought admitted of its being done without injury to the land.
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