10 
BULLETIN 31, PORTO EICO EXPERIMENT STATION 
such as are typical of land usually set with coffee. As has been 
pointed out, this type of land is not well suited for making compara- 
tive plantings. In 1912 the Erecta planting contained 199 trees in 
25 rows running with the slope. These rows were grouped into 5 
plats, each containing trees on both the upper and the lower slope. 
During the period covered, a number of the trees died and had to be 
replaced by others which were not included for yield averages until 
they were 5 years old. In 1924, 187 trees remained in the planting. 
The two Padang plats contained 115 trees in 1912 and 105 trees 
in 1924. Though approximately uniform as to area, the advantage 
PO/NTS DETERMINED 8/ TREES /N 
D/VS./-2 2-3 3-4 4-S 
Rs4TE Of FERT/UZER PER TREE PER S?PPL/C/?T/ON 
'A -'/2 POUND '/s-/ POUND P2 POUNDS 2-4 POUNDS 
KEVTO SSAPH SH0W/N6 F£er/UZ£BS APPLIED 
SYMBOLS /JSE COMB/NED TO /HD/CATE 
EEBT/UZEe COMBJNAT/ONS 
CHECK- - 
J SUl 
I SOI 
UME 
PHOSPHO£/C AC/O 
POTASH 1- + + + + + + + + + 
[4/fMOMUM 
N/T20GEW s^e*™ 
m 30000 
jzaeooo 
% 
\26000 
\24000 
^22000 
**£0000 
\#000 
, /6O0O 
W4000 
§/2000 
^/OOOO 
§8000 
§S000 
4000 
2000 
Fig. 5. — Average production per tree for the 8-year period 1917-1924. South Field plats 
of location lay with the check, which contained fewer trees on the 
less fertile upper slope. 
All plats were set with young seedlings in 1909. Beginning with 
1910 and continuing to date, the trees have been fertilized semi- 
annually, usually in December and in May or June. The plats were 
treated with a 7 : 10% : 14 fertilizer combination, the initial applica- 
tion being made at the rate of one-half pound per tree, and subsequent 
applications at the rate of 1 pound each. Individual terraces were 
