FARMERS' REGISTER— EXCRETIONS OF PLANTS. 



157 



Tliis la,^t accidental experiment is more con- 

 vinciiio; than either of the others; here the two bins 

 were tree Irom weevil, and the corn which was 

 separated li'oni theui, only by a loose board parti- 

 tion Avas filled, and I have little doubt,, would have 

 been rendered unfit for use before the summer was 

 over. Perhaps, Mr. Editor, in giving you and 

 your readers the information detailed in this paper, 

 I have been carrying "coals to Newcastle;" it" so 

 light your spn-it lamp with it, and I shall be satis- 

 lied, as my only object is to do good and not to see 

 myself in pruit. 



With my best wishes for your restoration to 

 liealth, and success in your pursuits, I remain 

 your friend. z. 



ON THE EXCRETOUY POWERS OF PLANTS, 



By Mr. Towers, Author of the Domestic Gardener's 

 Manual. 



From Uio [British] Journal of Agriculture, of 1834. 



The paper, at page 320 of this volume of the 

 Journal, enthled "De Candolle's Theory of the 

 Rotation (Jrops,"* refers to one of tlie most inter- 

 esting disquisitions that has ever claimed the at- 

 tention of the agriculturist. It is on a subject 

 that may perhaps stimulate the farmer to reflection 

 and experiment, and tend to abate that prejudice 

 which has but too extensively induced the culti- 

 vator to view the reasonings, and even the dis- 

 coveries, of scientific men, as so many innovations 

 upon the beaten path of routine practice. 



Upon these considerations, I hail the appear- 

 ance of this article, which I have perused and 

 reperused, again and again, with fresh satisfaction. 

 But, while I earnestly recommend the intelligent 

 agriculturist to study it witli deep attention, and 

 cordially join in the hope expressed by the Editor, 

 "that the chemists of our own country will prose- 

 cute the interesting investigations of M. Macaire;" 

 — while I thus urge the ti^rmer to study, and the 

 man of science to investigate, the theory, it is but 

 justice to myself to vindicate my own claim to 

 originality, — comparatively so at least in respect 

 to the hypotheses brought Ibrward at this time, 

 and said to be established by facts. I disclaim 

 wholly the idea of detracting from the merits of 

 any author, or of building upon any man's foun- 

 dation; but when I perceive that a theory is ad- 

 vanced or claimed as recent, which I can prove, 

 beyond a doubt, to have been pointedly and dis- 

 tinctly advocated by me above three years since, 

 I conceive that I am imperatively called upon to 

 make public, by the means at my command, those 

 remarks upon the excretory powers of plants, 

 wliich I penned in the year 18.30. 



They Avho are in possession of the Domestic 

 Gardener'' s Manual, will obser\'e, that when no- 

 ticing the '^Rotation of Crops,'''' at paragraph 539, 

 page 430, of that work, I add, — "A rotation of 

 crops is considered by most to be of absolute ne- 

 cessity; and chiefly on the supposition that each 

 plant draws a somewhat different nourishment." 

 I am jircpared to admit that each individual vege- 

 tablt^ elaborates its own specific nutriment; that is, 

 it induces decompositions, which aflbrd it a supply 

 congenial to its own peculiar habit and constitution. 

 I also advocate a rotation or change of crops, 



* For the theory of De Candolle referred to above — 

 sec page 317, vol. 1, Farmers' Register. 



not, however, on account of the necessity of re- 

 cruiting an exhausted soil, but for the reasons 

 adduced at paragraph 499, under the article 

 '^liaspberry.''^ 



Referring to that paragraph, page 397, we find — • 



"Experience proves, that to have a consttuit 

 supply of fine fruit year after year, the ground must 

 be frequently changed. Thus, after the rasjjber- 

 ries have borne fruit four or five years, one or two 

 roots should be taken up, the strongest suckers 

 selected, and immediately planted in fresh ground. 

 Whenever rasj)berry ])lants are removed to ano- 

 ther situation, the old ground ought to be well 

 manured, deeply digged, and turned; and then it 

 sliould be placed under some vegetable crop. By 

 this mode of treatment it will be brought into a 

 condition to support raspbeijies again in two or 

 three years. This is a curious and interesling fact, 

 one which proves that it is not solely by exhaust- 

 ing the soil that certain }dants deteriorate, if planted 

 in the same ground, year after year; for, were 

 this the case, manure would renovate the ground; 

 but it fails to do so, and thus, if peas or wlieat, for 

 example, be grown repeatedly on a piece of land, 

 the farmer *tnay manure to whatever extent he 

 cliooses, his crops ivill dwindle and become poorer 

 and poorer. This is remarkably the case in the 

 Isle of Thanet, where, to use a local term, if the 

 land be " orerpea'ti, " it becomes as it were poi- 

 soned; and if peas be again planted, though they 

 rise from the soil, they soon turn yellow, arc 

 '[/bxed," and produce nothing of a crop. 



"To account for this specific poisoning of the 

 soil, we must suppose thai particular plants convey 

 into the soil, through the channels of their reducent^ 

 vessels, certain specific fluids, which in process of" 

 time saturate it, and thus render it incapable of 

 furnishing those plants any longer with wholesome 

 aliment. In fact, the soil becomes replete to ith fecu- 

 lent or excrementitions matter; and on such the in- 

 dividual plant which has jdeldetl it cannot feed : 

 But it is not exhausted; so far from that, it is, to ali 

 intents and purposes, matured for a crop of a dif- 

 ferent nature; and thus, by the theory of inter- 

 change between the fluids of the plant and those 

 of the soil, we are enabled philosophically to ac- 

 count for the benefit which is derived from a 

 change of crops." 



It was thus that I expressed my opinion in 18-30, 

 and by the above quotations of two passages from 

 the Gardener's Manual, I think that I have in- 

 contestably established my claim to priority. It is 

 stated in the article on M. De Candolle's Theory, 

 (page 324,) that "Brugjnans had supposed a por- 

 tion of the juices which are absorbed by the roofs 

 of plants are, afier the salutiferous portions have 

 been extracted by the vessels of the plant, again 

 thrown out by exudation from the roots, and de- 

 posited in the soil." This may be the fact, nor 

 am I disposed to deny that two men may enter- 

 tain the same ideas upon any subject, without any 

 intercourse Avith, or assistance from, each other. 

 Still I assert, that the theory I adduced was, at 

 the time, purely my own; for, I cannot trace in any 

 accredited author, the least hint of the facts alluded 

 to.* Indeed, in a letter received m May last from 



* The opinion of Professor Lindley, published in 

 1832, in his "Outlines of the First Principles of Hor- 

 ticulture," is at page 19, i^i paragraphs 52, 53, 54, and 

 55, thus expressed; — 



