Sept, i, 1897 .] 
THE TROPICAL AGRICULTURIST. 
2or 
ance have not been suokerecl, and (those for my 
“ idea ’’) I would not wish to see better. 
I should be much obliged if you would kindly 
let me have your opinion on my views. And you 
can make what use you like of this letter if it will 
be of assistance.- -Yours, Ac., 
(Signed) GEOBGE A. GHEIG. 
[Mr. Green’s h : ter in renhj.) 
Et< a, Pnndaluoya, July 2nd. 
Geoiige a. Gkeig E Suduganga, Matale. 
Dear Sir, — Please excuse delay in replying to yours 
of 2Sth ult., but I have been very busy the last few 
days, and could not hud time to give your letter the 
attention it deserved. 
I will commence by repeating part of a circular 
which, in conjunction with fvlr. Willis, I have drawn 
up for di.stribution through the cacao districts, It 
runs as follows ; — “From personal examination (on the 
spot) of a large number of diseased trees, we are led 
to the conclusion that the canker is the outcome of 
some obscure constitutional disease or weakness, the 
cause of which is still undetermined (whether due to 
fungus, to over-cutting, insufficient shade, or old age) ; 
but that it cannot be directly attributed to the work 
of any insect. The diseased patches on the bark were 
frequently found to originate quite independently of 
any insect attack; though any wounds, unclosed 
knot holes, or insect borings were found to aggravate 
the disease by permitting the water to enter and 
permeate the inner layers of bark. On the older and 
weakened trees, a very large number of the cankered 
patches were distinctly traceable to open knot holes 
where suckers or branches had been torn o/f— affording 
lodgment for water and small insects. On yoirng and 
vigorous trees all such wounds were repaired by a 
renewal of the bark. We should be glad to know how 
far these observations agree with your own.” 
Now returning to your letter, — -brieily stated, your 
theory seems to be that canher is niainli/ due to the 
practice of sucherinQ the trees. And you base your 
argument on the supposition that cacao trees in good 
soil are weakened htf over-hearing, and are not allowed to 
recoup themselves hg the free growth of fresh wood. 
I think there is a great deal to be said 
for your theory — and on more extended 
grounds even than you give. As you will note 
by my earlier quotation I am of opinion that 
the disease is the outcome of weakness, and though 
I was not in a position to nrake the assertion, I 
personally suspected the weakness to be largely due 
to over-cropping which sapped the vitality of the tree 
and besides predisposing it to disease, prevented the 
healthy repair of wounds. 
ft is a very general rule, whicli is lieing constantly 
corroborated, that the more vigorous tlie growth of a 
plant, the less liable it is to attack from insects or 
other pests. It is when the flow of the sap is retarded 
or its nature altered by weakness or cih -r causes, 
that the plant falls an easy prey to blights of all 
kinds. It is evident therefore that a system of 
reducing or concentrating the cropping area, v.H Ji 
n 'Cessarily exhausts the plant, woiill piredispose it to 
the disease. 
Not being myself a cacao planter, I am not able 
to speak with any authority upon the actual methods 
of cultivation of that particular pjroduct ; but from 
an outside point of view and from observations made 
during the examinations of this disease, I should 
think it would be more profitable to encourage the 
growth of several stems or limbs than to confine the 
ti ea to one main stem. I noticed durii g my recent 
visit to Matale that though these old stems continued 
to produce flowers, very little of this blossom ac- 
tnilly pro duced fruit in snob situation, the bulk of 
the^ crop being borne on the more vigorous limbs 
and brandies. My inve.stigalions also plainly sh.iwod 
that tile canker w.rs pni.ctically confined to the old 
weakened stem. Young trees and the more vigorous- 
growing Eorestero variety were almost entirely free 
from the disease. fla\ ,) you ever tiier! stumping 
the yonng plant to induce it to start several stems 
from the base '? With regard to your suggestion to 
entirely step the practice of “auckeriug.” I should think 
there must be a limit to the number that could be left 
with advantage, but you on the spot must be in a better 
position to decide that question. But wherever suckers 
have to be removed, the work should certainly be done 
carefully and the wound stopipeci with some water- 
prroof mixture. 
Although with careful treatment, such as you suggest 
it may be possible to keepr the red cacao free from 
canker, still there seems to be no doubt that the 
Eorestero is a much hardier plant and more capable 
of resisting disease of all kinds. Attention cannot 
be too strongly drawn to the advisability of selecting 
ha.idy disease-resisting varieties in any cultivation. 
It is a most fortunate circumstance that there are 
such disease-resisting ,-tocks in so many cultivated 
plants. In the low-country of Ceylon the immunity of 
the Assam indigenous tea from Helopeltis is most 
marked and convincing. Particular varieties of potatoe 
were long ago found to be more or less proof against 
the potatoe disease; and rust-resisting varieties of 
wheat have been most successfully cultivated in 
Europe. In the case of Phylloxera the scourge of 
the continental vineyards, prarticnlar stock was found 
that resisted this insect pest, and tliough the fruit 
of this variety was not so prrofii.able as that of the 
more delicate vines the difficulty was overcome by 
grafting the more valuable variety on to the hardier 
stock. This last hint might prerhaps priove valuable 
to cacao planters. It would be interesting to ti-y the 
effect of grafting the more delicate Red cacao' to a 
hardier Eorestero stock — Yours &c. (Signed) 
E. ERNEST GREEN, 
CACAO DISEASE. 
Crystal Hill, July 2lst. 
Sir, — Mr. G. A. Greig of Suduganga, Matale, 
whose coirespondence with Mr. E. E. Green, on the 
cacao disease now prevailing appeared in your paper, 
will be siu'prised to hear that his next door neigh- 
bour so long ago as the year 1890, discovered that 
it was a mistake to remove the suckers aud gor- 
mandizers from the cacao tree as it not only tended 
to weaken the tree by depriving it of its “breath- 
ing lungs;” but also helped the old wood to har- 
bour insects which eventually destroyed the trees. 
Put the tiien piroprietor of this property, uie late 
Mr. A. G K. Borron, like nrany other i Id j i n. 
ters, did not believe in it. Two years after, givat 
mortality ensued among the cacao in ihe dis- 
trict, aud it was attributed to a deficiency in the 
rainfall and want of more shade to the trees. Every- 
one then resorted to planting dadap trees as shade. 
The year fo lowing was no better both w’ith regard 
to tliG rainfall and tlie disease ; but just then 
this property became my own, and enabled me to 
1 lit my theory into practice at once. The result 
may now be seen by any one who wishes to do so, and 
liie visitor will be well repaid for his trouble 
wlieii seeing that while the mortality is still con- 
tinuing among my neighbours, I am enjoying a perfect 
immunity from it.* 
Mr. .1. H Jdarber paid me a friendly visit two years 
ago, and surprised me not a little when be observed 
that I was doing just what he had also been doing 
on his property, “ The Grove ” Ukuwala, i. e. he 
allowed the cacao tree to grow aocoidiiig to its 
natural habits. He had been to the West Indies, the 
home of the cacao plant, and iiad seen for himself 
tliat tills was the latv there. 
It would be presumptuous on my piart, though a 
pilanter of 20 years’ standing, to express any opinion 
bearing on the scientific notions of Mr. Green; but 
Slice tliat gentleman has liinl the modesty to acknow- 
1 dge that he himself was not a cacao pi .uter, I make 
bold to remark that if by grafiing (as he suggests) 
the delicate C e I'lo or Car v'ca-! over stoc'i.s of the 
hardier Forester ), we succeed in projiioing a disease- 
resisting variety of cacao, still I doubt that the pro- 
* We should like to know if Mr. Vanstarrex means 
that diseased Bed Cacao trees after allowing suckers 
to grow, fully recovered '.‘—En. T.A. 
