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goes as low as 45 degrees, but a temperature above 50 degrees is 
preferred. As to rainfall, Ceara does best where there is 50 to 
120 inches of rain per annum. The best Ceara I saw was in a 
district where the rainfall is only sixty inches per annum. The 
trees will grow in rainier districts, however, but tapping is not so 
successful as in drier districts. Photo No. 24 shows some Ceara 
trees growing in the Botanical Gardens at Buitenzorg in Java, 
where experiments in Hevea rubber tapping are being carried on 
very carefully. The rainfall at the garden is 180 inches per an- 
num. The Ceara trees shown in the picture are 8 years old and 
though they grow tall, the largest is only 24 inches in circum- 
ference three feet from the ground, while the others are much 
smaller. 
On arriving in Ceylon, I found that there was only one estate 
on which there were Ceara trees being tapped to any extent and 
the output on this estate amounted to only 4,000 pounds of rubber 
per year. 
The main planting on the estate was Cacao, Cocoanut and 
Ceara Rubber trees being planted for shade. No new Ceara rub- 
ber trees are being planted out, but from the young trees that 
spring up the best only are allowed to grow while the poorer ones 
are cut out. As a rule these trees are 20 inches in circumference 
three feet from the ground when they are three years old and are 
then old enough to be tapped profitably. The manager thinks that 
the yield is greater when the trees shed their leaves. The growth 
of these young trees varies a great deal and trees that get a start 
when the weather is showery in the morning and sunny in the 
afternoon grow quicker than those that sprout when the weather 
is too rainy and is cold at night. An ordinary curved pruning 
knife is used in tapping on this plantation. The bark is cut 
through the cambian to the wood, removing a piece of bark an 
eighth of an inch wide. ''V" cuts are made one above the other 
a span apart but no vertical cut is made, the latex being allowed 
to flow over the bark. The manager claims that they get less 
scrap rubber in this way. The tree is tapped until an inch of wood 
is exposed. Photos Nos. 26 and 27 illustrate this method of 
tapping. The other side of the tree is tapped in the same way 
and then the tree left until the bark grows over. There is not 
the "wound response" in the Ceara that there is in the bark of 
the Hevea tree so that in tapping by this method an eighth of an 
inch of bark is removed each time the wound is reopened in order 
to get a good flow. With the Hevea it is only necessary to reopen 
the wound and the thinner the shaving the better. On account 
of the "wound response" the flow of latex increases as the tap- 
pings proceed up to a certain point. This is not the case with 
the Ceara which is more apt to be the other way. 
