June 1, 1903.] THE TROPICAL 
AGRICULTURIST. 
84^ 
CASTILLO A RUBBER. 
We camior, well understand what Mr. G. C. 
Pearson writing in Modem Mexico as quoted 
below means, when lie condemns Ceylon .as 
unfit to grow Castilloa rubber, proifitablyi 
We cannot see tlaat the figures quoted for 
yield by him in respect of Mexico .and 
Central America are so much more favourable 
than those of the late Dr. Trimen on which 
the condemnation is apparently based. Mr. 
Weber got 2 oz. rubber from 6-year old 
trees and reckoned he could have doubled 
this per annum or 4 oz. Dr. Trimen reported 
over 7 oz. hard rubber from his trees of same 
age. Prom 12 year old, Mr. Weber got 8 6 oz ; 
Dr. Trimen from 11 -year old 25 Vounces— so that 
how Mr. Pearson can say the Ceylon figures 
are unfavourable, is very puzzling. But there 
is some confusion ; elsewhere, we are told 
Mr. Weber's result equalled 11-^ oz rubber 
from a 6 year old tree, and Mr. Pearbon him- 
self reports 3J oz, from a tree 4J-year old, and 
rather more from other trees of same age. 
That the yield depends on climate and soil 
as Mr. Pearson tells us, is fairly well- 
known, but it depends also on the methods 
of tapping, the most suitable varying ac- 
cording to climate. It is tliought by those 
best able to judge that a series of " V " cuts, 
made spirally round the tree, will be the 
best suited to the trees grown in the Ceylon 
climate. 
Referring again to the subject of figures, 
the more businesslike are those given in 
a report in the India Rubber World of the 
experimental tapping on a regular plantation. 
The details will be found on page 844,atid the 
result is 112 lb. rubber per acre of 200 trees, 7 
years' yield ; 174 lb. at S years; 240 Ib.at 9 
years; and 314 lb. at 12 years— or lib. 9 12 
oz. per tree, against 1 lb. 9 7 oz. got by Dr. 
Trimen from 11 year old trees. So that Ceylon 
again scores. 
The great fact, remains, namely, that there 
is a ready, profitable m.irket for all the 
rubber likely to be available for a long time 
to come, 
THE YIELD OF THE CASTILLOA TREE 
( Vt riltcn for " Modern Mexico " by George Cullen 
Pearson.) 
Well may an English writer in a recent article 
say that ' the question of the amount of rubber 
yielded by the easlilloa is ciiaracterised by a degree 
of discrepancy perfeclly appalling.' To instance 
this: According to Cross, the well-known Kew 
botanist, a castilloa of from 18 to 24 inches in 
diameter produces 13 pounds of rubber annually, 
and that exceptionally large trees may give as much 
as UO pounds ! 
Collins observed ' that a 6 year old castilloa pos 
sessing a diameter of 19 inches ' (where can supli a 
development be found ?) 'on being tapped in April 
in the dry se;iPon, turnishcd 20 gallons of latex from 
which -19 pounds of rubber were obtained,' and 
he further declares that this is the average yield ot 
all trees, the trunk of which before branching out 
reaches a height of from 18 to 27 feet above the soil. 
Dr. Morriy, one of the foremost liotanista, now, I 
believe, director of the Botanical Department in 
the >Vest Indies, states that a catilloa when first 
tapped should yield 16 pounds of rubber. If ruy 
memory is not at fault, Dr Morris has stated that 
the first tapping should take place at 6 years. 
In Nicaragua it is found (in consular reports) that 
a castilloa tree yields from four to .six pounds of 
rubber annually. In the U. S. Consular lepoit for 
October, 1896, I find that 'if the trees have matured 
properly' iu the sixth or seventh year from eight to 
twelve pounds of rubber can be taken from each 
tree biennially ! 
The Bureau de Informations Agricoles de Mexique 
is more conservative, giving the yield oi castilloa 
trees when 4 to 5 years old at 2 pounds 6 ounces 
of rubber. 
Certainly the range is wide enough according to 
these statements, selected from many similar, 
showing that the yield of rubber, even of trees not 
exceeding 6 years' growth, may be anything from 
2 pounds 6 ounces to 49 pounds annually. 
Now, I am not in a position to prove that these 
statements, coming as they do frc m official and 
authoritative sources, are not co rtct. I can only 
say that having given considerable attention to all 
points connected with rubber cultuie, my own ex- 
perience does not bear them out AtkI i prefer, in 
common with all who have seriously taken up the 
cultivation of rubber, to base my calculations of the 
probable return.s on facta as asceitained by actual 
experiment. The following aie the results as 
obtained myself of the yield of the castilloa :— The 
greatest amount of rubber I have secured from one 
tree was 125 pounds, which I obtained from .30 lb. 
of milk— about 46 per cent of solid rubber. This 
was the result of tapping a tree growing on my 
property which measured two meters nine inches in 
circumierence— 87 inches — at six inelies from the 
ground. I niay heie .state tha^ an old hulevo 
(native rubber collector) who has worked much with 
me and in whose statements I have learned to place 
exceptional belief, a man of long experience, who 
has collected rubljer in all parts of the Kepublic, 
told nie that the most he ever found a tree to yield 
was 20 pounds of solid rubber, which he obtained 
from an exceptionally large tree measuring three 
meters in circumference — 117 inches— growing in a 
wild part of the State of Oaxaca. Ke believed the 
tree to be from 40 to 50 years old. On Novemler 
24th last I tapped six trees, aver.iging 40J inches in 
girth with a net result of 7 pounds 15^ ounces of 
rubber. These trees were con)paratively lightly 
tapped. If they had been operated on in the whole- 
sale fashion of the native colle.?tor at least half as 
much agiin would have been obtained. On Nov. 
ember 30th I tapped two trees of the respective 
circumference of 63 and 60 inches, obtaining there- 
from 6 pounds 2J ounces of rubber. As to the aa;e 
of these trees I can say nothing, as they are wild 
trees growing on the property. On December 3rd 
I tapped a rubber tree planted by myself, age 4 
years 4 months, girth 26 inche.*, height 27 feet, the 
result being 2^ ounces of rubber. Eight days after 
ward I again tapped the tree and obtaine<l f of an 
oance of rubber, making total product 3| ounces. A 
few days later I tapped ten tree=, age 4 years and 
4 months, average girth 23 inches, obtaiuir.g there- 
from 22 ounces of rubber. These trees could all hare 
been bled again, the second operation in no way 
affecting the tree, as I proved by the first-named 
experiment. In both cases the quality'of the rubber 
after preparation was excellent, (^n Decen)l>er 7th 
I tapped a tree of the age of 3 years and 4 moDth.«: 
result i ounce of rubber of poor qualitj-, 
sticky and littU life in it. It need hardly be r«. 
