THE GENESEE FARMEE. 



m 



Let us glance a \Qoment at a few of these experi- 

 ments, selected from hundreds giving similar results. 

 The experiments on wheat and on turnips were 

 made on soil of similar character, and which had 

 been impoverished by the growth of four crops 

 without manure, previously to the commencement 

 of the experiments. Wheat was grown success- 

 ively on the same land every year, as also were 

 the turnips. The wheat on the laud without any 

 manure produced, the first year, (18i4,) IG bushels 

 per acre ; the second year, 23 bushels ; the third 

 year, I7i bushels; and, on an average, about 

 the same in subsequent years, varying a little 

 with the season. Last year, (1857,) the four- 

 teenth crop which has been removed in succes- 

 sive years from tins soil Avithout any manure 

 was over 18 bushels per acre. Now mark the dif- 

 ference between this result and that obtained on 

 similar soil where turnips were grown without 

 manure. The first year, (1843,) the unmanured 

 plot yielded 4^ tons of turnip bulbs per acre ; 

 "the second year, 2J tons ; the third year only 

 13-1 cwt. per acre; and in subsequent years, the 

 production was even still less, the turnips being no 

 larger than radishes, though throwing out very 

 large roots in search of appropriate food. 



It is evident that this soil, which contained suf- 

 ficient plant-lood for the production of a fair crop 

 ■of wheat, was not capable of growing turnips, from 

 a deficiency of the ingredients of plants. In other 

 words, turniijs require in the soil, a larger quan- 

 tity of some constituent or constituents of plant- 

 food than icheat. "What that constituent is was 

 discovered by the use of the different constituents 

 of plants on other plots of turnips in the same field. 

 Potash, soda, magnesia, sulphate of lime, salt, am- 

 monia, — all these various constituents of plants were 

 sown on different plots, but none of them, sepa- 

 rately or together, supplied the deficiency — none of 

 them enabled the soil to produce a good crop of 

 turnips. But wherever superphosphate of hme 

 Avas used, there the turnips rioted in more than 

 pristine luxuriousness. On a plot adjoining that 

 without manure, and which, in 1845, produced 

 only 13^ cwt. of turnip bulbs per acre, 534 lbs. of 

 superphosphate of lime per acre enabled the soil 

 to grow nearly 13 tons of bulbs per acre, or about 

 tioenty times as much. 



This is not the result of an ordinary hap -hazard 

 experiment, but one of many hundreds aftbrding 

 sunilar results, and extending over a period of ten 

 years, conducted with great care, and by men of 

 science and practical experience, who devoted their 

 entire time to these and similar investigations. Now 

 what do these facts prove ? Do they not demon- 

 strate that turnips require for their maximum growth 

 more phosphoric acid (superphosphate of lime) in 



the soil than wheat ? This is all that is claimed — 

 iiot that phosphoric acid is a special manure for 

 turnips. Phosphoric acid will not produce a good 

 crop of turnips, if any one of the other mineral con- 

 stituents of plants is deficient in the soil ; but what 

 is claimed is this: that in the majority of cases, 

 soils are deficient in available phosphoric acid for 

 the growth of maximum crops of turnips, though they 

 may at the same time contain enough for the pro- 

 duction of a large crop of wheat. No crop we are 

 acquainted with, requires so much available phos- 

 phoric acid in the soil as turnips, and therefore, 

 there is no impropriety in stating that "phosphoric 

 acid is specially suited to the growth of turnips," 

 though the expression may not convey precisely 

 the idea intended. 



The same remarks will apply in regard to ammo- 

 nia being " specially suited to the production of 

 wheat." The experiment of Lawes & Gilbert 

 prove that a soil may contain sufficient phosphoric 

 acid even for the growth of turnips, and an abun- 

 dance of every other mineral constituent of plant- 

 food, and yet not yield a maxunum crop of wheat, 

 hut loill do so when supplied with ammonia. Super- 

 phosphate of lime, which had such a magical effect 

 on turnips, had no effect on the wheat grown on a 

 similar soil ; other mineral manures had no effect ; 

 but wherever ammonia was used, the crop was 

 greatly increased, and in some instances more than 

 doubled. 



Prof. Johnson says there are "other equally 

 authentic trials which as fully prove just the 

 reverse."" If there are, we have never seen any 

 account of them. 



AMEKICAN AGEICTJLTUEAL BOOKS. -No. 3. 



OuK correspondent B., in his "Suggested Items," 

 alluding to previous articles on this subject, inti- 

 mates that the books noticed last month can hardly 

 be considered as '■^American.'''' This is true. They 

 were not written by Americans ; neither are their 

 practical recommendations, in many cases, adapted 

 to our climate and circumstances. Their princi- 

 ples, so far as correct, are of universal application. 

 The writings of Boussingault, Johnston, and 

 Stockhaedt, are, in the main, as well adapted to 

 America as they are to France, Scotland, or Ger- 

 many. "When we used the phrase "American 

 books," we intended merely to designate such as 

 were published in this country. The fi\ct is, we 

 have, strictly speaking, very few American agricul- 

 tural books. Many of those purporting to be such, 

 are little else than compilations from British au- 

 thors. So long as the country can be flooded with 

 cheap reprints of English works, we can hardly 

 hope for distinctive American agricultural books, 

 of real value. The demand for them, at the price 



