432 



THE FARMER'S MAGAZINE. 



PRINCIPLES OF MANURING. 



Lawes' and Liebig's Controversy on the Principles of Manuring popularly explained. — 

 The Rothamsted Expkriments with Special Manures described. — Unmanured and 

 Manured Corn-growing preliminarily considered. 



As a means of illustrating both the principles and 

 practical bearings of this celebrated controversy, it is 

 impossible to select a more apposite, instructive, or 

 important instance than that presented by the well- 

 known agricultural triumph in successive and un- 

 manured wheat-growing achieved by the Rev. Samuel 

 Smith, at Lois Weedon. The manner of his yearly cul- 

 tivation is as follows : At the usual time in autumn, the 

 seed is drilled in strips, which (consisting, as each set 

 does, of three rows ten inches apart) occupy thirty inches 

 in width, and between strip and strip there is left an un- 

 seeded space of similar dimensions. During the growth 

 of the plants in the ensuing season, the rows receive 

 sedulous attention in hand-hoeing ; while, at the same 

 time, the interspace between strip and strip undergoes a 

 constant succession of horse-hoeing and other fallow 

 operations. Next year these fallowed spaces bear the 

 strips, and the stubble of the preceding year's crop is 

 ploughed up and summer-fallowed in like manner. In 

 one point of view, there is a perfect analogy between 

 this expedient, and a practice not uncommon on the 

 heavy land of Essex, in which is pursued field by fieid 

 the simple altc rnation of corn one year and bare fallow 

 the next, to be again succeeded by corn, and so on for 

 ever ; but in various circumstances of detail, into which 

 we shall not here enter, the Lois Weedon meihod pos- 

 sesses a superiority very favourable to both healthy and 

 prolific cereal productiveness. Mr. Smith's experience 

 in this mode of management dates back to the year 

 1846. The area of his operations is comparatively 

 small, being only live acres. The soil is above average 

 quality, and consists of a staple of good wheat land, 

 resting on wholesome clay, and naturally dry. The im- 

 plement used for inverting the soil is the spade, or fork, 

 in place of the plough. The average yearly produce for 

 twelve years, ending with crop 1859, has been upwards 

 of thirty-six bushels per acre of prime marketable corn; 

 and the expenses of tillage, rent, &c.j are as follows : — 



Table I. 



& 8. d. 



Digging and cleaning 1 14 



Horae-hoeing, three times 6 



Ploughing 4 



Hoeiug and hand-weeding 5 



Three rollings with crushers at seed-time and 



at spring 3 



Two pecks of seed 2 6 



Dibbling 5 



Bird-keeping 4 



Earthing-up wheat 3 



Reaping, &c , thrashing, and marketing 1 13 



Rent £2, rates and taxes 4s. 3d 2 4 3 



Total yearly expenses £7 3 9 



Value of thirty-six bushels of wheat at an 



average price of 6s. 6d. per bushel £11 14 



Deduct expenses as above 7 3 9 



Annual profit per acre besides the 

 value of the straw £4 10 3 



One other element of Mr. Smith's practice still re- 

 mains to be stated (and on account of its paramount im- 



portance it has been reserved for special notice), namely 

 this, that in each summer fallowing of the interspaces a 

 method of deep cultivation is pursued, by which the 

 upper and under strata of the staple are stirred, and in- 

 verted to the depth of ten or eleven inches ; and if it be 

 asked upon what grounds was this trenchant and very 

 thorough tillage resorted to, the reply is, because theory 

 and practice alike assured the experimentalist — Ist, 

 that usually in the soil, and ever in the air, there is an 

 abundance of nutriment for cereal crops, in proportion 

 as the mineral and atmospheric elements are brought in- 

 to mutual reaction within the pores of the soil, by per- 

 fect cultivation; and hence, 2ndly, that by means of 

 perfect tillage, the aid of adventitious fertilizing sub- 

 stances is not indispensable to the profitable growth of 

 corn. 



In point of agricultural importance, no industrial cir- 

 cumstance belonging to the present century is more 

 entitled to deep consideration, than this brilliant, yet 

 sound instance of tentative husbandry ; nevertheless, in 

 order to appreciate its true practical value, it is neces- 

 sary to bear in mind, that as respects the happy com- 

 bination of operative details of which it is made up, it 

 consists of no principle or expedient in cultivation which 

 had not been known and practised before. As an exam- 

 ple of cereal productiveness, procured without the inter- 

 vention of cattle crops, what other unalternate system 

 than this prevailed in England, when, prior to the in- 

 troduction of roots and clover in rotation, she not only 

 fed her own population with corn, but exported it 

 largely to foreign parts ? Nay, more — what other than 

 this, is the still existing policy in the cereal countries of 

 continental Europe, which now so largely provide Eng- 

 land with breadstuff's. As for the interculture of the 

 Lois Weedon method, admirable and efficient as the 

 expedient is, it can be regarded simply as an adaptation 

 to corn tillage of that method of drill husbandry hitherto 

 confined in general practice to the fallow crops only ; 

 while finally, the deep working, if not so generally 

 prevalent as it ought to be, has long existed in many of 

 the best-farmed districts of the island. 



Now, the moral we wish to point out, in the foregoing 

 statement, is this — that, from the case where, under 

 sunny skies, and on a rich soil, the lazy husbandman has 

 only to scratch a little covering of earth over his corn seed 

 to produce an abundant crop, up to the elaborate pro- 

 cesses of Lois Weedon experience, there is every variety 

 and degree of evidence to show that wheat or any other 

 kind ol grain can profitably be raised by the power of til- 

 lage alone, and that the use of manures, whether obtained 

 from the cattle crops of modern rotation husbandry, or 

 from external resources, is not indispensably necessary 

 to profitable cereal husbandry. Nay, more — from the 

 practice of all nations it is deducible, that in pro- 

 portion (within certain bounds) to the greater depth to 

 which a soil is stirred, and to the perfect annual tillage it 

 receives, the produce of that soil will be more abundant. 



From these inculcations of unmanured and purely 

 tillage husbandry, we now turn to the doctrines of a 

 very different school, namely, those taught by the well- 

 known authors of the Rothamsted experiments in agri- 

 cultural practice, and in proceeding first to describe 



