30 
BULLETIN 31, PORTO EICO EXPERIMENT STATION 
Table 14. — Development of young coffee trees as affected by the nitrogen car- 
rier, frequency of application, and, sulphur 1 
Kind of 
soil 
Clay. 
Loam 
Treatment 
f Ammonium sulphate, semiannually applied. 
Sodium nitrate, semiannually applied, plus sulphur. 
Sodium nitrate, semiannually applied 
Sodium nitrate, applied monthly, plus sulphur 
Sodium nitrate, applied monthly 
Sulphur — 
.Nothing (check) 
Ammonium sulphate, semiannually applied 
Sodium nitrate, semiannually applied, plus sulphur. 
Sodium nitrate, semiannually applied 
Sodium nitrate, applied monthly, plus sulphur 
Sodium nitrate, applied montlhy ' 
Sulphur.. 
.Nothing (check). 
Average 
number 
Average 
weight 
Average 
height 
per tree 
of leaves 
per tree 
of leaves 
per tree 
Grams 
Inches 
107.8 
67.6 
45.8 
99.2 
70.6 
45.8 
81.3 
54.8 
40.0 
116.6 
81.4 
45.4- 
98.8 
65.3 
43.4 
42.1 
27.8 
35.2 
58.8 
36.6 
38.2 
56.9 
32.9 
35.4 
53.3 
31.2 
32.1 
39.6 
23.4 
30.9 
114.9 
67.1 
39.1 
78.6 
52.5 
39.4 
19.3 
8.9 
25.1 
19.6 
7.1 
23.9 
Average 
weight 
of trunk 
and 
branches 
per tree 
Grams 
118.4 
118.6 
80.7 
127.7 
103.0 
54.8 
69.6 
86.7 
61.8 
48.0 
106.9 
105.1 
20.3 
18.9 
1 Data taken at close of the test, July, 1925. 
Thirteen of the 80 trees in loam were dead at the close of the test, 
whereas of those grown in clay 1 was dead, 1 destroyed, and 1 was 
excluded because of its poor condition unrelated to fertilization. 
Counts of the leaves per tree were made at quarterly intervals. 
is 
8! 
it! 
VI 
! 
1 
/eo 
//o 
/oo 
90 
60 
70 
60 
SO 
40 
30 
20 
/O 
5 
I 
1 
I 
58 
xer TO iMJWH showing rttriLiites Amao 
SYMBOLS ABE COMB/A/SO TO /MHCAT£ 
F£em.i2£e comb/kations 
CH£CK ' ~T£iiSSJM\ 
LIME --'--'--■! 
PHOSPHOBtC AC/O 
POTASH h+ + + + + + + + + 
SULPHU8 OOO OOOOOOO 
J&L 
7%T^ 
I 
5 
<2J 
*> -^ 
-77 
Fl0 17 — Development of leaves on young coffee trees as affected by the nitrogen earner, 
frequency of application, and addition of sulphur. M indicates monthly applications of 
nitrogen. Otherwise, applications were made semiannually 
Figure 17 graphically shows the average number of leaves per tree 
produced in clay soil. The trees showed differences due to fertilizer 
during the first year, but to a much less pronounced degree than a 
little later. The curves show that ammonium sulphate and sodium 
nitrate plus sulphur were very effective in increasing the number of 
