July 2, 1883.] 



THE TROPICAL AGRICULTURIST. 



33 



— -^ 



To the Editor of the '■'■Ceylon Observer r 

 MR. STORCK ON VEGETABLE PHYSIOLOGY. 

 Belmont, Rewa River, Fiji, April 10th, 1883. 



Dear Sir, — I have always with much interest fol- 

 lowed any publications in your paper which could 

 serve to give me an insight into the present physic- 

 al condition of the coffee-fields of Ceylon, which is 

 more or less intimately connected with the cure of 

 the fungus as practised and recommended by me ; 

 and nothing has ventilated that question so well as 

 the writings of your correspondent "W." and the 

 answers and controversial remarks thereupon elicited 

 from others of your readers, especially as to the im- 

 portance of foliage to plant life. 



The functions of plant-life are twofold : firstly 

 structural, and secondly progenitive, or repro- 

 ductive. Both these functions have by the cultivator 

 been taken advantage of for commercial purposes, and 

 the importance of the foliage remains the same, whether 

 the marketable portion of a plaut is gained from its 

 structural parts, roots, stem, or leaves, as roots, fibre 

 or the monstrosity called a cabbage, as when a coffee 

 berry, a peach, or even a favourite flower, is aimed 

 at by him. Keep persistently pulling off the 

 leaves of the commonest weed, it will die ; off a 

 growing carrot plant, it will make no root ; off a 

 cabbage plant, it will Viot make a "head"; off a 

 coffee bush or a peach ti-ee, it will not bear. And 

 whilst in all or any of these cases an always feeble 

 and often premature blossom or effort at seeds, that 

 means at reproduction of species, may take place, you 

 will as often find it die before making this im- 

 potent attempt. 



Through having been violently, continuously and un- 

 seasonably deprived of those most important structura 

 organs, the leaves, the conductors and elaborators of food 

 their breatliiug org»ns, and, iu the instance of coffee 

 and fruit trees, the natural shelter of young wood and 

 young crop, your coffoo-flelds have arrived at the stage 

 you now see them in. It is through the leaves that 

 plants draw their chief supply of carbon (an element 

 without which the formation of a plant is simply imposs- 

 ible, as the analysis of any vegetable matter shows) 

 and in turn exhale the superfluous nitrogen generated 

 within its tissues — surely ample reasons for their un- 

 imp.iired preservation. Hemihia vasiatrix and its effects 

 upon the foliage are quite suflioieut to account for all 

 that "ails your caffeo trees." What Dr. Hooker said in 

 his professional opinion on Hcmihia vastatric is certainly 

 very abstruse. UcmiUia vastatrb: is Jiot a disease, but the 

 cause of one, a most emphatically legitimate object for the 

 action of Government, as shown by precedents in other 

 countries with other epidemics. The features of the 

 matter dictate an oxaiuinatioa of its life-history in 

 a ecieatific sensi, with a view to curative measures 

 based upon the knowledge so gained and subsidii-ad 

 by Government. The disea-e iu your gum trees is 

 just as much the effect of a fungus and a leaf-disease 

 a iu your coffee trees : loss of foliage and dying 

 back of e.xtremities are the same, but the gumtree 

 very likely succumbs sooner because strictly speak- 

 ing it is not a tropical forest tree but with you 

 an exotic. [Dr. Triiuen could find no sign of fungus 

 on the gums. — -Ed.] 



I was rather surprized at "W." trying to prop up 

 his argument by putting the loss of foliage by prun- 

 ing on a par with that lost by tlie wholesale 

 ravages of leaf-disease. Pruning is a species of am- 

 putation by whicli you remove after proper selection 

 any structural irregularities of shape, and secondly 

 superfluous growth which presently or prospectively 

 interfere with the conditions of the highest roproductive- 

 5 



nesa for commercial purposes, i. e. "crop." Other 

 trees besides the coffee — the apricot, the peach, the 

 grape — are heavily handled iu full flush and for 

 the same reasons. The juices of the amputated 

 limb or cavity are diverted from waste to productive- 

 ness. But just i)uU off only the leaves of a tre , 

 leaving the bare wood to draw upon the physical 

 powers of it for a new coat of foliage, without which, 

 as shown above, the tree cannot live, you will, if 

 ^ you repeat the process often enough, constitute a 

 parallel to leaf-disease. Loss of foliage through in- 

 sects, wind, or cropping, as with tea, is a different 

 matter again. They seldom occur often and regularly 

 enough to do lasting harm, and, when they do, there 

 is generally enough of foliage, leaf stalks, ribs and 

 shreds of leaves— with tea, old leaves — left to ke?p up 

 a circulation until by renewal of foliage the balance 

 of supply and demand, the organic functions of the 

 foliage, is restored. 



With Hemileia vastatrix and its ravages it is 

 a different thing : they occur so repeatedly and 

 persistently, as to undermine, independently of 

 crops of berries produced in previous seasons, tho 

 physical stamina of your coffee trees and their 

 by this time indirectly deb'.litated progeny that 

 the plant becomes impotent to mora than in a restricted 

 manner perform its reproductive functions, and is com- 

 pelled from very poverty to coufiue itself to its struct- 

 ural duties, the ever and ever reimposed labor of 

 replacing its indispensable foliage, to enable it to live, 

 e.xist, vegetate. I have elsewhere compared leaf-dis- 

 ease and its effects to a sort of arithmetical progression, 

 which continues until the sum of its duplications and 

 reduplications is equal to the original physical power 

 of the coffee tree. This means, iu other words, that 

 the debilitating effects of one season will be doubled 

 the next, at first but slowly, but, as powers of resist- 

 ance decrease, ever more fatally and rapidly as season 

 follows season. This is only meant to apply to the 

 coffee tree as a commercial plant, without :akiug into 

 account the counteracting influence of more or less 

 intelligent and liberal treatment in working and man- 

 uring, about which so much ha' been ably said and 

 written, that I would find it diiScult to Siiy anything 

 new or suggest anything better thi'i has as yet 

 appeared. A plaut in its wild stat'j is oi course equally 

 subject to tho laws of nature, but less an object of 

 solicitude to man. 



Although I have not heard much lately about the 

 carbolic acid treatment against the fungus, I was glad 

 to notice that it is not abandoned and that'a party of 

 planters admit that they have ha I .results, whether by 

 my own system or another, and boldly declare that 

 carbolic acid does kill the fungus. I had told you so 

 and eminent chemists confirm id me in their opinion, 

 giving preference to the fluid indirect treatment to that 

 by tho powder; and time will prove them correct : bui 

 I do not. only profess to kill 90 per cent of the spores, but 

 all and utterly . I have done it aud will do so again. 

 Considering the vast importance to yon and all 

 iu the East, I would have expected greater inter- 

 est and hoped for better faith in my scheme. 

 In my own small plantation — I had to make an 

 entirely new start after having tho old fifid and 

 a large nursery destroyed by Government 3 years 

 ago and am besides cultivating a consider- 

 able area of caue, is perfectly free of leaf-disease, 

 Liberian aud all. A year ago I offered to arrange witli 

 other proprietors for trials on terms, but the only 

 response I had was tho magnificent offer of travelling a 

 hundred miles, bear all expenses, and treat one acre ! 

 What was the gentleman afraid of in making this 

 restriction ? He had probably never given tlie subject 

 a thought and suspected somethiug heroic. Others 

 seem to think : ' ' We have got it ( ll<:iiuleia ija.Htatrix) and 

 we must keep it. Allah is great !" I must confess to a. 



