EXPERIMENTS WITH COCONUT PALMS 
13 
only 287 palms remained in the last period. The plats thus varied 
slightly from period to period in number of palms included, ranging 
in the first period from 41 to 47 oalms each and in the last period 
from 40 to 42 palms each. 
The plats were treated at the rate of 5 pounds per palm with a fer- 
tilizer combination having as its basal formula 6 per cent nitrogen, 
8 per cent phosphoric acid, and 12 per cent potash. Applications 
were made twice annually from June, 1912, to June, 1916. The fer- 
tilizer was broadcast as far as the guard rows. The guard rows 
received at each side, respectively, the same kind and amount of fer- 
tilizer as was given to the adjacent test plat, in order to obviate rob- 
bing by the trees in the guard rows. Three plats were given incom- 
plete fertilizer, three were given complete fertilizer, and one received 
, nothing. Of the three plats receiving complete fertilizer, plat No. 
6 received double quantity, and in plat No. 7 the nitrogen was carried 
in dried blood. For all plats except the latter the nitrogen was sup- 
plied in ammonium sulphate. The other elements were supplied in 
superphosphate and in potassium sulphate. After a 5-year interval 
following the fertilizer applications, salt (sodium chloride) was 
applied semiannually from July, 1921, to January, 1924, to four 
plats. Two plats were given 2y 2 pounds and two were given 5 
pounds per palm per application. As was the case in the earlier 
applications, the salt was broadcast to the guard rows, for which salt 
was provided at the same rate for the area treated. Table 3 shows 
the fertilizer treatments. 
Table 3. — Fertilizer treatments, yield of coconuts, and distribution among the 
plats of the 50 least and of the 50 most productive palms, at Boquillas 
Fertilizer applied per 
palm from June, 1912, 
to June, 1916 
Amount of NaCl per appli- 
cation from July, 1921, to 
January, 1924 
Average yield of nuts per 
palm during — 
2 
*£» 
o 
Distribution 
among the plats 
of the — 
Plat No. 
i 
ft 
as 
*-> a 
gl 
gp. 
a 
fc 
■O 
C 
O 
\4 
First period, July, 
1913, to May, 
1915 
Second period, 
August, 1915, to 
June, 1917 
Third period, Sep- 
tember, 1917, to 
July, 1919 
Fourth period, 
October, 1919, 
to June, 1921 
Fifth period, Oc- 
tober, 1921, to 
January, 1924 
6 
2 J 
P. 03 
^> P. 
© > 
"C zn 
O 3 
,H ,3 
Ml c3 
— — 
o © 
a£ 
o 
"3 
1 
Lbs. 
5 
5 
5 

5 
10 
5 
P.ct. 
6 
6 


6 
6 
6 
P.ct. 

8 
8 

8 
8 
8 
P.ct. 
12 

12 

12 
12 
12 
Lbs. 
2H 

5 


5 
2H 
No. 
68.7 
60.9 
65.5 
71.6 
76.3 
77.7 
69.8 
No. 
54.7 
45.3 
51.6 
61.8 
75.9 
80.5 
73.1 
No. 
158.7 
60.9 
68.3 
70.7 
71.1 
68.8 
65.5 
No. 
44.7 
36.7 
42.5 
46.3 
37.9 
33.3 
47.3 
No. 
33.8 
31.7 
32.8 
40.9 
36.8 
33.6 
50.5 
No. 
i 260. 6 
235.5 
260.7 
291.3 
298.0 
293.9 
306.2 
No. 
9 
7 
7 
5 
10 
5 
7 
No. 
3 
2 
9 
5 
3. 
4 
8 
5- 
11 
6 
7 
7 
10 
1 In the twenty-fourth harvest the record from 5 palms in plat No. 1 was not obtained, the nuts having 
been removed previous to entry. This fact was disregarded both in these and other calculations. Here it 
presumably reduced the average by approximately 1 integer. 
NUT PRODUCTION 
The production of each palm was recorded separately as in the 
other experiments. The intervals between harvests were not uni- 
form but averaged approximately three months. The first recorded 
harvest was in February, 1913, and the last in September, 1924. 
Through accidents the record was unobtainable for certain harvests. 
