HAWAII AGRICULTURAL EXPERIMENT STATION 
HONOLULU, HAWAII 
Under the supervision of the 
UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 52 
Washington, D. C. V July, 1924 
MANGANESE CHLOROSIS OF PINEAPPLES: ITS 
CAUSE AND CONTROL. 
Bv M. O. Johnson, 1 Chemist. 
CONTENTS. 
Page. Page. 
Yellowing of pineapples on manganese soils I 
Previous investigations en manganese. .. 2 
Investigations on lime-induced chlorosis.. 5 
Status of manganese problem when the present 
investigations were undertaken 6 
The manganiferous soils and their effect on 
pineapple and other plants 7 
An explanation of the physiological effects of 
manganese on plants.. 24 
A successful treatment 27 
Practical tests of the method of spraying 30 
Practical advice regarding the treatment 34 
Genera] summary and conclusions 35 
Literature cited ■ 36 
YELLOWING OF PINEAPPLES ON MANGANESE SOILS. 
The yellowing of pineapples grown on the manganese soils of the 
Hawaiian Islands was a serious problem to pineapple growers for 
many years. Large areas of these black or dark manganese soils 
are found in the chief pineapple-growing district lying on the sloping 
plateau between the Koolau and Waianae Mountain ranges on the 
island of Oahu. Such soils also occur in the very large potential 
pineapple areas on the islands of Molokai and Lanai, and to some 
extent on the islands of Kauai and Maui. None of these areas could 
be profitably utilized until a solution of the manganese problem was 
found. 
When pineapple plantings were first being extensively made in 
1902, prospective growers eagerly sought the dark soils, being influ- 
enced by the color which was thought to be indicative of great fer- 
tility. It was soon discovered that the pineapples on these soils 
suffered serious injury, a trouble which locally became known as 
i4 pineapple yellows/' or "manganese yellows." 
The most pronounced characteristic by which these pineapple 
plants were differentiated from normal plants was a gradual fading 
of the leaves until the whole plant assumed a yellowish-white appear- 
ance. Blanching of the leaves occurred at any period of growth, 
but usually started in three to six months after the time of planting. 
i The writer wishes to thank J. M. Westgate, agronomist in charge of the Hawaii Agricultural Experiment 
Station, for heartiest support and encouragement in this investigation, and J. T. Whitmore, S. T. Hoyt, 
and H. Blomfield Brown, of the Hawaiian Pineapple Co., for their generous cooperation and help. 
