xxvIII.-~S
E X P E R I M E N T S M'I1.H
~EK?.II,IZE:RS L'I'OS
AT CaIArrhii,r P T A ~ T A T II~OASY, o UY
SL'GAR-CANE,
~T. ~ C I I I..\. E?
Prtol.. C'. .I (. ;oEssMhNS
It has been niy pleasure, iii a previoiis coinniuiiicatiori, t o report through the PROCEEDISGS O B 'THK A X E I ~ I ~C~t IA n rSr c , t I . SOCIETY, Vol. II., No. 2, p. 5 2 , the results of a series of experiments with varioiis fertilizers upon sugar-cane, a t ('aluniet Plantation, Bayou Tbche, La. T h e importance of the local agricultural, :is well as the general industrial, interests involved in a certain solution of the object in view, have induced the progressive and puhlict-spirited proprietor of that plaiitation, Daniel I'horiiprori, Eq.,Pattcrsoiiville, Parish St. Mary, La., t o continue his investigations. The original plan for the tic~lti work, which was carried out for t w o successive years, 112s bcwi a1);inclonect. A new course of tixperimerits, proposed /I!/ the writer, at the special request of Mr. 'I'hornpsoii, has taken its place since the spi~ingof 1878. 7'he c.hange c ~ ) ~ i c e r n s teinatical applicatiori of the varioiis the details, and a h i s a t :i fertilizing materials, for tliv ~ W ~ J O W of imparting to tlie eventual results a better defined niennirig. 1 Iiacl ocmaion t o s t u d y , in 1)revioiis years, the general topographical and geologicd features of tlie locality where the experiments art. cmductetl, when visiting tlie Ihyori 'I'Gvkie, f o r several rnonths, as expert in ronriection wit tion, to inqiiiie iiito its industrial and coinnic physical contlitioii of the soil on trial. as well as the natiirv of its constitueiits arid latent natural r c ~ s o i i r w s of l,laiit-footl, I iiatl, reipeatedly, a g o d cliancr t o ascertain ~ J Y c*lic~niic:iltests. LI*the general character of the soil and the tcniporary supply of pl:tnt food, as f a r as the kind and the amount of each article is concc~riied,are known t o exert, in most instances, for some time, a controlling influence on the quantity and quality of the resulting crops, uiickr circumstances like those under consideration, I recoinrneiitled ;L time honored and well endorsed niode of operation, which, iiitelligeiitly c.arric?tl oilt, canriot fail to secure to the (*awfulobserver, i n a pr:irtic:d \vas, niiicli valuable information--a mode which every intelligerit farnier may turn to account, to smne degree at, least, for personal instruction in his own industry. I n the rn>rking rip of tlie cornpound riiauures, the refiise materials from Southern branches of :tgric.riltural iridustry, have been, for obvious reason*, in sevcral instances, selected. T w o points which the history of field experiments wit11 fertilizers, in an uiiqualified ni-anner, endorses, were beforehand c ~ n c ~ d enamely ~l, :
.
thrJ results ohtnhed f r o , n experiwpitts extending over u certain m m he/* of ymrs, (ire tcloue etititled t o serious coitsitZeratioiL ; ccnd even taell extnblishetl w s d t s r i w , i n most instames, e a s e d o l l y qf‘ l o c d wtrlrw. T h e general interest which a well devised series of field experiments with fertilizer.: may cltim, consists chiefly in its educational ititluence, serving as a lesson for similar investigations in other localities. W i t h these qualifications, the snbsequent detailed report of Mr. Thonipson’s first year’s work, upon the new plan, is not without some interest t o those engaged in agricultiiral field experiments in general. 1 he lands engaged in the trial consist of sixteen acres in one level body. All parts of the area are equally well drained. T h e soil is so far as general appearance may tell, of ail uniform mechanical and chctnival condition ; a fine dark brown, clayish loam, rich in rooty fibres. T h e entire ground has been treated alike since 1863 ; it was left uncultivated from that year until 1851, on account of the war, and berved sabqequently, alternately, for t h e production of corn and sugar-cane. Pea-vines were raised a t certain intervals for greennianurittg, with the exception of 1876, when 500 pounds of cottonseed meal, per acre, was used as a fertilizer. T h e entire tield has been divided into sixteen plat*, each one acre in size. Individual plats are separated by three r,ows of cane, of six feet each, making eighteen feet of unfertilized space between two adjoining plats. T h e canes have been harvested in the same order as the plats are numbered. T h e griiiding began on the 9th of December, and closed on the 16th of December. One day passed by, on an average, between the cutting and the grinding of each lot of cane. T h e latter Rere thus from twenty-four to thirty-six hours cut, before the test of the juice by the polariscope, etc., could be attended to. ‘J’he beason was very favorable for the cultivation of sugar-cane. In cww,eqiience of the absence of Mr. Thompson during the beginning of the grinding Reason, the crops of the first four plats failed t o be recorded and tested, much to his displeasure. T h e entire experiment, I am advised, is to be repeated, in all its details, during the present season (see accompanying table). r ,
1 'Muriate of Potash. 2 Sulphate of Potash
S Cotton Hull A s h . , 1 AirSlaked Lime.. 5 G y m m
. . . , ....
1 I 6 Acid Pho. Lime
,,
.
7 Sulphate Ammonia
Cotton S. Hull Ash Acid Pho. Lime. Air Slaked Lime.. Cotton S. Hull Ash Cotton S. Hull Ash IGypsum.. . . . . , . . . . , [Cotton S. Hull Ash /Cotton S. Meal. . , .
16 1Nothing.
..........
~
.I
Ammonia
47 111
. . . . . . . . . . . . . . . . .I ~. . . . ,$7.3
I 22393i9.50115 0 19.012Mi~
T h e results, although in s e w r a l instances quite remarkable, are, on the whole, b: no means unusual. Without any intention to enter, a t this early stage of the inves tigation, upon a detailed discussion of the various experiments, it seems quite Aafe tc assume, first, that the richness of the soil still largely controls the results ; sild sec
E'XI'ERIMENTS WITH FE1WILIZB:RS VPON S U G A R C A N E .
419
ond, that a cliferev?t degree qf maturity of the cane, from the various plats, exerts a serious influence on the total amount of available caibe Mugar, as stated above. T h e last named circumstance is plainly shown by t h e remarkable differences noticeable in t h e percentage yield of t h e juice from the different lots of cane, varying from 52.2 t o 66.2 per cent.; and also, by the not less striking differences in the composition of the juice, indicated b y the results of the specific gravity test, b y means of the saccharometer, which represents the relative total amount of solid matter in solution in the juice, atid the tests by the polariscope, which expresses only the relative amount of cane sugar present in t h e latter. T h e actual differences in these testa are due t o t h e presence of more or less foreign nitrogenous and non-nitrogenous substances.
As the above described experinients are instituted mainly for the purpose of finding a fertilizer which will assist in producing, iipon a given area, the largest amount of cane sugar possible, and, a t the same time, a cane which coiitains, in its juice, the highest possible percentage of cane sugar under favorable circurnstances for separation, the subject of inquiry is of more than ordinary intricacy. A brief reference t o experiments Nos. 5 and 13 in.Ly not be without interest in this connection. Vpon these two plats the total amount of available sugar and of canes, differ in quite different proportions: for the excess of sugar exceeds that of the cane nearly three to one in favor of plat No. 5 . This plat had received as fertilizer only gypsum (sulphate of lime), at a money value of $2.50 per a c r e ; whilst No. 13 had received, what ordinarily would be designated, a complete fertilizer, containing besides a liberal amount of potassa, phosphoric acid and nitrogen, a considerable share of sulphate of lime or gypsum, the whole at a money value of $14.45 per acre. To ascribe, judging merely b y the yield of sugar and cane, to the gypsum alone a higher power for aiding in the production of vegetable matter-cane sugar included-than to the combincd effect of a liberal additional supply of all t h e essential mineral constitiients of plants, as in the case of No. 13, would be in contradiction to t h e teachings of the best established experimental observations in agriculture. A continuation of these experiments, i t may be confidently expected, will find a more satisfactory explanation iri a favorable reaction of the gypsum, on either t h e physical condition or the chemical composition of a rich soil, or in some unsusperted comhination of oircunistances favorable to an early maturing of the caries.
