POTATO DISEASES IN HAWAII AND THEIR 
CONTROL. 
CONTENTS. 
Page. 
Introduction 3 
Prevention and control of potato 
pests 4 
Potato diseases known to occur in 
Hawaii 15 
Page. 
Potato diseases not known to occur 
in Hawaii 36 
Conclusion 41 
INTRODUCTION. 
The growing of Irish or white potatoes in Hawaii was at one time 
a relatively important industry. According to Sedgwick, 1 in the 
middle of the last century potatoes stood at the head of the list of 
exports and in 1849 the number of barrels exported was 51,957. 
Since that time production has dwindled and consumption increased 
until, in the year 1916, 189,212 bushels were imported from the coast 
States, an amount approximately equal to former exports. Various 
factors, not the least of which is the introduction of diseases, have 
tended to make the growing of this crop difficult, while repeated crop 
failures and discouraging marketing features are potent elements in 
lessening production. The largely increased consumption has re- 
sulted from the proportionate increase in the number of people using 
this crop. 
A considerable quantity of potatoes is still raised in the islands in 
spite of the frequent crop failures. The greater part is grown in the 
Kula and Makawao sections of Maui and near TVaimea and Hama- 
kua, Hawaii. Small patches of from one-quarter to 5 acres are the 
rule, and a considerable quantity is grown for home use. An ap- 
proximation as to the present annual production is hard to reach, 
though it is probably not in excess of 30,000 bushels. 
As a sound agricultural policy it is desirable that this languishing 
industry be fostered, and that so far as possible the Territory be 
self-supporting with respect to this commodity. It is believed that 
by the application of improved cultural practices, fertilization, and 
pest-control methods present production can be doubled or trebled 
without any increase in acreage. The present rate of import of 
this staple furnishes an indication of the available market. 
Since the writer came to this station in 1916, attention has been 
largely devoted to a study of the potato crop and the reasons for 
1 Sedgwick. T. F. Potatoes. Hawaii Sta. Rpt. 1901, p. 374. 
