138 
The Philippine Journal of Science 
1921 
on each, tree in August, 1917, at the beginning of the experi- 
ments, and in August, 1918, when the experiments were com- 
pleted, are shown in Table 5. 
Table 5. — Showing degree of canker affection of trees in untreated plat, 
Plat II, of the College of Agriculture citrus planting at Los Banos 
Species. 
Leaves affected. 
August, 1917. 
August, 1918. 
Per cent. 
20 
Number . 
Per cent. 
50 
Number. 
95 
( b ) 
( b ) 
8 
Do 
0 
0 
5 
2 
Do 
3 
1 
Do 
5 
1 
Do 
0 
0 
1 
Citrus mitis 
10 
10 
Do 
2 
5 
Citrus limonia 
1 
Do 
5 
5 
Do . 
6 
6 
Do 
2 
1 
Do 
1 
1 
Do 
2 
10 
Citrus hystrix 
0 
0 
0 
0 
1 
5 
Do 
2 
5 
Do 
1 
(*>) 
( b ) 
2 
10 
10 
5 
Do 
7 
4 
Do 
0 
0 
9 
Do 
7 
11 
Do 
i 
15 
66 
10 
60 
100 
0 
0 
0 
0 
6 
1 
6 
1 
m 
25 
1 
Do 
20 
1 
Do 
3 
50 
40 
5 
0 
0 
1 
Do . _ 
0 
0 
0 
0 
28 
9 
Do ___ _j> 
18 
5 
a The determination of the species mentioned in this and subsequent tables is taken 
from a chart of the college orchard at Los Banos made available through the kindness 
of Mr. Mariano G. Medalla, instructor in the College of Agriculture, University of the 
Philippines. The measurement of the amount of canker on the leaves at Los Banos in 
August, 1918, is also largely to be credited to Mr. Medalla. For this and for much other 
assistance the writer wishes to express his sincere thanks to Mr. Medalla. 
b Dead. 
