ANDGARDENER'SJOURNAL. 



f UBLISHEU IJV JOSEPH li KKCK & CO., NO. 52, NORTH MARKET STREET, (Agricultuh*l Wabeuou.e.) 



VOL.. XVI. 



^^m^^WlL^W^^'SLa 



BOSTON, WEDNESDAY EVENING, NOVEMBER 29, 1SS7. 



NO. 21. 



(From tJje Genesee Farmer.} 



GREEN CROPS AS A MANURE. 

 Tlie question hns been somttiines a.^ked, " why 

 freen crop.s are valuahle as a nianiire, .since wlia-- 

 iver may be the kind of plant, or niagriitnde ff 

 he growth, it can retnrn to the soil no more tliau 

 t takes from it." The query liere supposes th:it 

 he nourishnipnt is aheady in the earth, and inigl t 

 s well lie applied Hirectiy to the iirowih of tl-^ 

 rop itself, as to the one which sindl he turned in 

 3r a manure ; — or, in other words, that wher.' 

 le green crop is hinkwheat, followed by wint< c 

 rain, the grain nii;,-ht as well derive its nonrish- 

 lent direct from the earth as to give the fnrni' 

 le trouble of sowing, growing, ami liicu plonj;l< 

 ig in the huckwhi-.u which is destined to fi. - 

 ish it. 



There are twosourees of fallacy in this rea''on- 

 ig, which it may be well to point out ; though it 

 •onid seem hardly necessary in a country where 

 toveras a green crop, and a preparative for wheat, 

 in so general use, that no one can fail to pcr- 

 ;ive its benefits. The first source of error is lo 

 3 found in the supposition that plants derive ill 

 leir iiourishinent from the earth ; and the sec i.i 

 , that matter which has once i)assed through e 

 •ocess of vegetable organization, is no ' .-■' 

 lapled to the nutrition of plants, than that which 

 IS never been submitted to such an action, both 

 hich suppositions it is believed are contrary to 

 e fact. 



Plants do not derive all their nourishment from 

 e earth ; on the contrary, much of it is derived 

 om the air. The ingredients that enter into the 

 rmation of plants are very few and simple. The 

 lief of them are carbon, hydrogen and oxygen ; 

 id in some few nitrogen in small quantities. It 

 the various combination of these few principles 

 at constitute the interminable of vegetables and 

 jgetable products. It is true that in most plants 

 aces of the earth and metals, such as potash, so- 

 1, lime, magnesia, silex, aluniiue, sulphur, jihos- 

 lorus, iron, manganese and muriatic acid, are 

 icasionally found, but they are rarely to be con- 

 lered as constituent parts of the plant, their 

 •esence is accidental, and they contribute in no 

 ay to the nutrition of the vegetable. Of the 

 bstanceg mentioned^ above, the one which con 

 ibutes most to vegetable growth, constituting al- 

 ost entirely the frame-work of the plant, is car- 

 >ii. This indispensable article can only be made 

 nilable by conversion into gas, in which state it 

 iinbines with water, and is taken up by the roots 

 is absorbed by the leaves directly from the air. 

 .e presence of carbonic gas is indispensable to 

 Igetation ; in germination it is absorbed by the 

 ^d ; in the young and lender plants by the root 

 incipally, as Seunebier proved that young leaves 

 composed less carbonic acid in proportion than 

 ives of full size, and of the latter ;i thousand 

 iperimeuts have shown that one of the most 



important functions is the providing the adcipiale 

 snp|)ly of carbon, without which vegetation can- 

 not exist. The hydrogen and the oxyyen are 

 mainly provided in the same way, that is, from the 

 atmosphere surrounding the plants. 



But we are not left to the uncertainty which 

 sometimes attends vegetable analysis by chemical 

 means. Evidence which can he understood by 

 all, hag been furnished in abundance. The case 

 of Van Helmont and his willow is probably fa- 

 miliar to most, and is [lerfectly conclusive, as to 

 the fact that plants do not derive all their nour- 

 ishment from the earth. Planted in a close lead 

 box ; both the earth put in, and the plant itseif 

 carefully weighed; watered only with distilled 

 water, it was found after several years of vigorous 

 growth, that the willow had gained some two hun- 

 dred pounds in weight, while the earth in the box 

 had lost but a few ounces lii.stilling water does 

 not entirely free it from all earthly salts, hut the 

 quantity left is scarcely perceptible by the nicest 

 analysis, and of course the nutriment received by 

 this tree must have been mostly furnished by the 

 leaves, the juices necessary for its approjiriat-on 

 being furnished by action of the roots. In addi- 

 tion to this experiment, there are some plants, 

 such as the common ' live forever ' of our gardens, 

 which will grow foi a longtime when totally sep- 

 nraleA from the roots. The eastern plant called 

 ;."■ ' r-. ;•'•■£., < i^fe everlasting,' is so tnnacious 



of vitality, that it is i^sed for f.jrn.ii.g f-^i^ , r.!. 



the walla of rooms, curtains, &c., where plants 

 in any other form could not be permitted, and 

 here it grows, and flourishes, and blossoms for 

 months, living as it clearly must wholly on air. 

 Thero therefore can be no reasonable doubt that 

 plants iieturn to the soil, if ploughed in when in 

 full vigor, more than they take from it, and that 

 in this respect, green crops are eminently benefi- 

 cial. 



It is, we think, no less true that plants wlien 

 decomposed are more readily convertible into new 

 plants, than matter which has yet to undergo the 

 first processes of organization. 'J he decomjiosecj 

 matter contains precisely the ingredients, and 

 nearly in the same [iroportions, required by the 

 growing plant, and of course is taken up with a 

 facility which would be impossible, were any fuo- 

 cesses of preparation necessary. This is further 

 evident from the nature of mould, or that great 

 reservoir of nature's manure, provided to assist 

 tlie growth of [dants. All plants when dead, are 

 more or less readily decomposed, and when all 

 the parts of a plant have undergone this change, 

 there is produced a residuum, of a brown color, 

 earthy in its appearance, and which is called 

 mould. It is to this substance mixed with the 

 other earths, that land owes its fertility, as with- 

 out its presence, or principles analogous to it, all 

 soils would clearly be sterile. 



Nowhere can the formation of mould, or of 

 earth suitable for the growth of plants be more 

 clearly seen than in the islands of the South Pa 

 cific, where in a single cluster of islands, tiie whole 



process is at once lirought before the eye. First 

 is the coral r. . f rising to the level of the sea, the 

 millions of v.nrms that have raised the stujien- 

 dons sirnctin;; from unfathomable depths, perish- 

 ing as thi'y ladiialiy become exposed and leav- 

 ing at last a iough nnd porous rock above the high- 

 est tides Then come the sea fowl or other birds, 

 bringing the seeds of plants with them, or the 

 germs are floated from other islands. Soon the 

 rock is covered with lichens and mosses which 

 grow, and (l(ci'y,and mix with the finer particles 

 of the rock decomposing under the action of the 

 atmosphere. More perfect, and higher organized 

 plants now take root, and the process goes on un- 

 til they liecome the habitations of man, and are 

 covered with grijjres of the palm, the plantaii and 

 the bread frajK-:* Thus in all cases the lower de- 

 grees of organization prepare the way for the 

 higher, the lichens and the mosses foT the cereal 

 grains and the grasses, these are converted into 

 animal flesh by the action of or^'anized vitality, 

 and tills in .is turn is made subservient to the 

 growth and nutrition of man. It is absurd to sup- 

 pose that plau!s will not flourish better when their 

 food is pre.s<'oted to thi'in in an already partially 

 organized si do, as it would be to imagine that 

 man woul<l iirrive his nourisliment "nsier by going 

 back to firs'. ,)iinciples, and licki the dust for a 

 livelihood: ' '-stead of feeding on the organized 

 pork cl> <p, ■St'»*un cutlet, or lusc' -s beefsteak. 



T!;r pfu-tciS ^1' lura-no- Jr. ™pc.t-. __ ii,o ..v h ..-leih- 

 od of fertilivi(ig soils, and preparing thrm To. ii^j 

 produc;ion of other and more valuable crops, ap- 

 pears then to be well founded on scientific prin- 

 ciple, and where the practice has been followed, 

 the results have been sufficient to justify any rea- 

 sonable expectations that might have been formed 

 from it. Farmers well know that where crops 

 are allowed to inannre their seed, and are then 

 taken of!', what they can return to the soil is but 

 comparatively a trifle to what it is when the same 

 crop is jiloughed in green. They know too that 

 a succession of ripened crops, no matter what they 

 may he, will exhaust the most fertile soils in time, 

 and leave them unfit for cultivation. This is the 

 case at present with a large portion of the South- 

 ern States. Continual cropping, without the re- 

 lief alFordcd by green crops, has in many ))laces 

 reduced the average product of wheat to 6 or 8 

 bushels per acre, and that of corn to 10 or 15. — 

 On the other hand, Dutchess, one of the best farm- 

 ing counties in the United States, has been made 

 what it is, and mostly within the last forty years, 

 by the practice of alternating green crops with 

 grain ones. In Dutchess, as in western N. York, 

 clover is the favorite plant, and this with plaster, 

 will in ordinary cases produce the ilesired efTect 

 of enriching the soil, as well as furnish fine crops 

 of grain. We have an ii.iiircssion, however, and 

 some experiments would seem to justify the opin- 

 ion, that where an immediate effect is required, 

 it can be more speedily produced by buckwheat 

 than by any other green crop. Jf a piece of land 

 is to be sown with wheat in the fall, there is no 



