18 
BULLETIN 3 4. PORTO EICO EXPERIMENT STATION 
tion of the 50 least productive palms was 106 nuts, that of the 50 
most productive was 494.2 nuts, which is a ratio of 1 to 4.7. The 
distribution of these low and high yielders among the plats is given 
in Table 3. When it is noted that the check plat No. 4 and the 
most heavily fertilized plat No. 6 differed only in the check having 
one additional highly productive palm, and that plat No. 5, a fer- 
tilized plat and adjacent to the check, had twice as many low-yielding 
palms as the latter, no 
correlation can be seen 
between fertilization 
and the number of low 
or high yielding palms 
in a plat. 
Huts 
110 
100 ■ 
DRAINAGE 
As this field is only 
very slightly above sea 
level and in" places is 
inclined to be swampy 
in 
season, a 
the rainy 
survey was made to 
learn whether or not a 
correlation existed be- 
tween production and 
elevation, in this case 
the equivalent of 
drainage. The elevation 
above sea level 2 was 
measured to one-tenth 
inch of a point within 
several feet of, and ap- 
proximately on a level 
with, the base of each 
palm. The elevations 
were found to range 
from 4.2 to 9.2 feet 
above sea level. Figure 
12 shows the elevations 
diagrammatically. 
If the palms in each 
plat are grouped accord- 
ing to the elevation 
of each palm and the plats are compared, it is seen that the two 
plats which had the greatest number of palms at elevations of 7 feet 
and over, and also the fewest at elevations below 6 feet, were the 
most productive, whereas the least productive plat had the greatest 
number of palms at elevations below 6 feet. The average elevation 
Figure 11. — Average nut production per palm, by 
periods of eight harvests each, of the 50 most pro- 
ductive and of the 50 least productive palms, Bo- 
quillas plantation ; the former in solid, the latter 
in shaded blocks 
2 Sea level was determined May 15, 1926, at 10 a. m. Tide at this hour at Fajardo was 
0.85 foot above the datum of mean low water. High tides at 11.15 a. m. and at midnight 
were 0.95 foot and 1.8 feet, respectively, above mean low water. These data were fur- 
nished by R. J. Auld, executive officer, Steamer Ranger, U. S. Coast and Geodetic Survey, 
who stated also that comparisons had shown that the difference in tidal action between 
Fajardo and San Juan was negligible. Presumably, the tidal action on the west coast 
would not be greatly different. 
