342 annual purchasers of these extraneous fertilising substances to the extent of 20s. to 30s. worth for every acre occupied by them. To enforce the same restriction on such men as on others who buy none at all is obviously neither just nor politic ; and we believe that any practical farmer, if he had his choice, would rather be the successor of a liberal mauurer, however he may have cropped, than of one who has farmed by rule on the starving system. We are quite aware that, in regard to the first-mentioned of these restric tions (viz., that which forbids taking two grain-crops in immediate succession), the contrary practice is still asserted by agricultural authorities to be necessarily bad farming. Now, we do not concur with this opinion, but believe, on the contrary, that when land is kept clean, and is as highly manured and well tilled as it must be to grow cattle-crops in perfection, the second successive crop of grain will usually be better than the first, its production nowise injurious to the land, and the practice, in such circumstances, not only not faulty, but an evidence of the skill and good manage ment of the farmer. A frequent encomium applied to a particularly well-cultivated farm is, that " it is like a garden." The practice of market-gardeners is also frequently referred to as a model for farmers. Now, the point with them is to have every inch of their ground under crop of some kind at all seasons, and to carry everything to market. Under such incessant cropping, the fertility of the soil is maintained only by ample manuring and constant tillage. By these means, however, it is maintained, and the practice is extolled as the perfection of management. Such a system must therefore be as true in fanning as in gardening, when the like conditions are observed. Undoubtedly he is a good fanner, who, while keeping his land clean and in good heart, obtains the greatest produce from it at the least proportion ate outlay ; and it is no valid objection to his practice merely to say that he is violating orthodox rotations. Section 3. Experiments at Rothamstead and Lois Weedon. Some curious information has been obtained regarding the effects of growing successive crops of one kind of plant on the same field, from two examples of it that attracted much attention. We refer to the experiments of Mr Lawes at Rothamstead, and of the Rev. Mr Smith at Lois Weedon. It is well known that Mr Lawes for a number of years devoted a considerable extent of land to the prosecution of a series of interesting experiments, one field being allotted to experiments with wheat, another to turnips, and another to beans. One acre in the wheat-field bore upwards of twenty successive crops of wheat without any manure whatever. The land was annually scarified and thoroughly cleaned as soon as the crop was removed; it was then ploughed and again, drilled with wheat, which was duly hoed in spring. Now, with occasional variation, due to the character of particular seasons, Mr Lawes found that the average annual produce of this acre was 16 bushels of grain and 16 cwt. of straw, below which he failed to reduce it by these successive crops. His soil was a strong clay loam, resting at a depth of five or six feet upon chalk. In the case of turnips, he found that, when treated in the same way, they cease after a few years to grow larger than radishes, nor could he, by the application of any .amount or variety of manure which he tried, obtain a second successive crop equal to the first. With the wheat, on the contrary, the addition of four cwt. of Peruvian guano at once doubled the produce. Mr Smith s experiments, as is well known, were a revival of Jethro Tull s system of growing wheat continually on the same field, by a plan of alternate strips of wheat and bare fallow, made to change places an- smally. He improved in so far upon Tull s practice, inasmuch ras he thoroughly drained his land, and his fallow spaces deeply trenched every autumn, as well as ploughed [MANURES. and hoed during the growing season. The result was that his land thus treated yielded an average annual produce of 34 bushels per acre for eleven or twelve successive crops. Now, it is not our intention to offer any opinion on this as a system of wheat growing. We refer to it along with Mr Lawes s, for the purpose of showing that, notwithstand ing the prevalent opinion that grain-crops exhaust the fertility of soil;* more rapidly than green crops, this is true only in a very restricted sense. Green crops judiciously interposed do undoubtedly serve a most important purpose in the means which they furnish for maintaining the fertility of a farm ; but it is worthy of note, that whereas, by the addition of suitable manure, thorough tillage, and diligent removal of weeds, clay soil at least will stand an indefinite succession of grain crops, the same means entirely fail to yield the same results with our most popular green crops. Our personal experience quite accords with this ; for we suppose it will be admitted that the corn crops of the country are at the present Jay superior, both in quality and quantity, to those of any preceding period ; whereas potatoes, turnips, and clover, which we have so long regarded as our sheet- anchor, have become increasingly precarious, and threaten to fail us altogether. We offer these facts for the consider ation of those who out-and-out condemn the practice of sowing two white crops in immediate succession. In stating this opinion, we must, however, guard against misappre hension. Unless the land is highly manured and kept thoroughly clean, we are just as much opposed to the practice as any one can be ; but when mischief is done by it, we believe that it is due rather to the presence of weeds than to the second grain-crop. Neither do we plead for the absolute removal of restrictive clauses from farm leases. Human nature being what it is, men who do not see it to be for their own advantage to farm well, will, through ignorance or greed, impoverish their land unless they are restrained. Clauses as to cropping should, however, be pro hibitory rather than prescriptive have reference rather to what is removed from the farm than to what is grown upon it and they should be contingent upon the other practices of the tenant. So long as he continues, by ample manuring and careful tillage, to maintain the fertility and general good condition of the farm rented by him, it can be no ad vantage to his landlord to hinder him from cropping it at his own discretion. It will be seen from these remarks, that we attach more importance to those general principles which should regulate the succession of crops, than to the laying down of formulas to meet supposed cases. The man who cultivates by mere routine is unprepared for emergencies, and is sure to lag in the race of improvement ; while he who studies principles is still guided by them, while altering his practice to suit changing circumstances. CHAPTER X. MANURES. Section 1. Farm-yard Dung. In our remarks on tillage operations and on the succession of crops, we have seen how much the practice of the husband man is modified by the kinds and amount of manures at his disposal. In describing the crops of the farm and their culture, frequent reference will also necessarily be made to the use of various fertilising substances ; and we shall, there fore, before proceeding to that department of our subject, enumerate and briefly remark on the most important of them. In such an emimeration, the first notice is un questionably due to farm-yard dung. This consists of the excrements of cattle, their litter, and the refuse of their fodder ; usually first trodden down in successive layers, and partially fermented in the farm-yard, and then removed to some convenient place and thrown
together in heaps, where, by further fermentation and decay,
