y 
UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 1040 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
Washington, D. C. 
PROFESSIONAL PAPER 
April 12, 1922 
CONTROL OF THE CITROPHILUS MEALYBUG. 1 
By R. S. Woglum, 2 Entomologist, and A. D. Borden, 3 Assistant Entomologist, 
Fruit Insect Investigations. 
CONTENTS. 
Introduction 
History and distribution 
Economic importance 
Host plants 
Description and life history. 
Seasonal history 
Page. 
l 
o 
3 
4 
4 
6 
Page. 
Relation to Argentine ant S 
Comprehensive demonstrations of 
control 8 
Natural enemies 19 
Summary 20 
INTRODUCTION. 
In the fall of 1913 a mealybug infestation was noted on citrus at 
Upland, Calif., over an area of approximately 3 acres. At first it 
was assumed to be the common mealybug (Pseudococcus citri Risso), 
a species highly damaging in some citrus localities but never before 
reported in the Upland district. Growers were considerably alarmed 
over the discovery, knowing the severity of this pest and the inef- 
fectiveness of control in other localities. Considerable damage was 
done to the infested groves in a hasty attempt at eradication by 
fumigation. At a convention held at Ontario, Calif., on January 
30, 1914, the seriousness of the problem was discussed, although no 
real solution was evolved. A specific determination was made at 
this time hj Essig 4 as Baker's mealybug {Pseudococcus maritimus 
Ehrh.), a species then considered as of minor importance to citrus. 
In September, 1915, Clausen, 5 after a brief investigation of the insect, 
1 Pseudococcus gahani Green ; order Hemiptera, suborder Homoptera, family Coccida?. 
2 Resigned September 11, 1920. 
3 Resigned December 5, 1921. 
4 Essig, E. O. The mealy bugs of California. In Calif. Mo. Bui., v. 3, no. 3, 
p. 110-111. 1914. 
6 Clausen, Curtis P. Mealy bugs of citrus trees. Univ. of Calif., Bui. 258, p. 
30-35. 1815. 
78472—22 1 
