XIV, 5 Yates: Growth of Hevea Brasilie'nsis 521 
dicate that the rate of growth in that country, while rather 
variable, is in general considerably less rapid than in Malaya. 
Johnson “ gives girth measurements of trees in the^Tarkwa 
Botanic Station, Gold Coast. Data from his table are presented 
in Table XVI. The rate of growth does not appear to differ 
greatly from that of trees of the same ages in the Philippines. 
Table XVI . — Growth of Para rubber at the Tarkwa Botanic Station, Gold 
Coast. 
Plot 
No. 
Date of planting. 
Distance planted. 
Girth at 3 feet from ground. 
December, 1905. 
December, 1906. 
1904. 
Feet. 
Meters, 
cm. 
in. 
cm. 
in. 
I 
June 
15 by 15 
4. 5 by 4. 5 
17.78 
7 
30.48 
12 
11 
do - 
12 by 12 
3. 6 by 3.6 
15. 24 
6 
25. 40 
10 1 
III 
July - 
15 by 15 
4. 5 by 4. 5 
15.24 
6 
25. 40 
10 
IV 
do - 
20 by 20 
6. 0 by 6. 0 
15. 24 
6 
27. 94 
11 
V 
do - 
30 by 30 
9.0 by 9.0 
10. 16 
4 
22. 86 
9 
VI 
- -- do 
40 by 40 
12.0 by 12.0 
10. 16 
4 
22.86 
9 
VII 
do 
12 by 12 
3.6 by 3.6 
10.16 
4 
22.86 
9 
VIII 
August and September 
12 by 12 
3. 6 by 3.6 
10.16 
4 
25. 40 
10 
While much additional information in regard to the growth 
of Hevea is available, it is believed that sufficient material has 
been presented to indicate that the rate of growth of Para rub- 
ber in the Philippines compares favorably with that recorded 
elsewhere. 
YIELDS OF HEVEA BRASILIENSIS 
The yield obtained from Para rubber trees now being tapped 
in the Philippines is very satisfactory and seems to compare 
well with that obtained in other countries from trees of the 
same ages. The rubber obtained in 1916 from 20,510 trees in 
tapping by the end of the year was 14,991 kilograms (32,982 
pounds), or an average of 0.73 kilograms (1.6 pounds) per 
tree. Almost 6,000 of these trees came into tapping during 
1916 and 11,000 in 1915. The oldest trees were between 8 and 
9 years of age at that time. Unfortunately no separate record 
has been kept of the yield from trees of different ages, and 
this renders difficult a comparison with the yields obtained in 
other countries. 
” Johnson, The Cultivation and Preparation of Para Rubber, 2d ed. 
(1909) 25. 
