UNITED STATES DEPARTMENT OF AGRICULTI 
DEPARTMENT BULLETIN No. 1225 
Washington, D. C. ▼ April 30, 1924 
THE CAMPHOR THRIPS. 
By W. W. Yothers. Entomologist, and Arthur C. Mason, Assistant Entomologist, 
Fruit Insect Investigations, 2 Bureau of Entomology. 
CONTENTS. 
Introduction 1 
History and distribution 3 
Origin! 4 
Comparison of bay thrips and camphor thrips 4 
Nature and extent of injury 5 
Page. Page. 
Seasonal history 18 
Host plants IS 
Natural enemies 21 
Control measures 21 
Summary 28 
Description 6 Literature cited 29 
Life history and habits 8 
TNTRODUCTION. 
Many years ago camphor trees, Cinnamomum camphora (L.) Nees 
& Eberm., were introduced into Florida for ornamental uses. The 
beauty and grace of the tree made it very popular for the beautifi- 
cation of grounds, roadways, and borders of groves. The ease with 
which this tree was propagated and the luxuriousness of its growth 
(fig. 1) led to the belief that it could be grown in large acreages to 
obtain a commercial supply of camphor. 
The first attempt to produce camphor gum under commercial 
conditions was made at Satsuma, Fla., in 1903. The total investment 
on this plantation amounted to nearly one million dollars and during 
the period of the existence of the plantation (1903-1921), 1,S00 
acres were set to camphor trees. Another plantation, consisting of 
2.200 acres of camphor trees, was located at Waller, Fla., midway 
between Stark and Green Cove Springs, and represented an invest- 
ment of over a million dollars. It was thought that by using machin- 
ery on an extensive scale camphor gum could be produced as econom- 
ically here as in the Oriental countries, where the cost of labor is low. 
Practically all of the work of planting the trees, cultivating, harvesting 
the branches for distillation, and producing the camphor gum itself 
was done by mechanical means. 
1 Cryptothrips flori(hnsi>< Watson; family Phloeothripidae, order Thysanoptera. 
2 The present investigations were begun by C. A. Weigel, of the Bureau of Entomology, assisted by 
C. A. Bennett, who conducted a large part of the field work during the first ;■■ ■ .ally all the 
biological work was done at Orlando, Fla., by the junior \\Titer, together with observations made at "the cam- 
phor farm at Satsuma, Fla. The control work was done mostly on the camphor plantation at Satsuma, 
and in addition pruning and spraying experiments were carried on at Orlando. Similar life-histor\ 
was carried on at Gainesville, Fla., by Prof. J. R. Watson, to whom credit is given for certain notes and 
valuable assistance. The writers desire also to express their appreciation to C. W. Loveland. manager of 
the camphor plantation at Satsuma throughout the period of the investigations, who extended to toeni 
many courtesies as well as material aid dming the progress of the work. 
6957S — 24 1 
