PORTO RICO AGRICULTURAL EXPERIMENT STATION 
MAYAGUEZ, P. R. 
UNITED 
Under the supervision of the 
STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 34 
Washington, D. C. 
June, 
1931 
EXPERIMENTS WITH FERTILIZERS 
ON COCONUT PALMS AND VARIATION 
IN PALM PRODUCTIVITY 
By T. B. McClelland, Director 1 
Page 
Fertilizer experiments 1 
San Jose plantation 2 
Corsica plantation 8 
CONTENTS 
Page 
Fertilizer experiments — Continued. 
Boquillas plantation 12 
Summary and conclusions . 20 
Coconuts valued at approximately $700,000 were annually ex- 
ported from Porto Rico before the hurricane of September 13, 1928. 
The storm destroyed many palms, but their loss is expected to con- 
stitute only a temporary drawback to the local development of the 
coconut industry. Most of the coast of Porto Rico is fringed with 
coconut palms. The area in this crop varies greatly in width but is 
generally rather narrow. The soils range from beach sand to sandy 
loam and are probably more uniform in texture than are those 
planted with most of the other kinds of crops. 
FERTILIZER EXPERIMENTS 
Cooperative fertilizer experiments on coconut palms were begun in 
1912 in Porto Rico by C. F. Kinman, former horticulturist of the 
station, and were continued by him until his transfer to the mainland 
in 1918. Since then they have been conducted under the direction of 
the writer. All field work was terminated by the hurricane of Sep- 
tember, 1928, which destroyed nearly two-thirds of the palms in the 
two groups then under test. 
The experiments were made on three plantations in different local- 
ities. The palms in each locality were in a different stage of devel- 
opment, and each group represented a distinct period in the life of 
1 The author gratefully acknowledges his indebtedness to A. J. Harvey, the Guanica Cen- 
trale, the German Kali Works, Cesar de Chudens, Jos6 Gonzalez, S. V. L. Lippitt, and 
William Whittemore, whose kindly cooperation made the experiments possible. 
52849°— 31 1 1 
