UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 902 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
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Washington, D. C. 
PROFESSIONAL PAPER 
October 22, 1920 
THE WESTERN CABBAGE FLEA-BEETLE. 1 
By F. H. Chittenden and H. 0. Marsh, 
Truck-Crop Insect Investigations. 
CONTENTS. 
Page. 
Nature of injury 1 
Description , 2 
Distribution 3 
Reports of injury 4 
Food plants 7 
Seasonal history 8 
Life history and habits 9 
Page, 
History and literature 13 
Natural enemies . - 13 
Control 14 
Recommendations 17 
Summary 20 
Literature cited 21 
NATURE OF INJURY. 
An insect enemy of cabbage, turnip, and other cruciferous crops, 
known as the western cabbage flea-beetle, ranks as a most trouble- 
some pest in the region which it inhabits. 2 
It is primarily an enemy of gardens, but quite too frequently 
becomes a pest in large commercial plantings. The chief injury is 
done by the overwintered beetles attacking turnip, radish, and other 
cruciferous vegetables just as they are coming through the ground, 
and by the beetles of the first generation, which are usually at the 
maximum of their destructiveness during June and July. The beetles 
appear suddenly, and frequently in incalculable numbers, and large 
areas are completely devastated before the grower becomes aware of 
their presence. 
Although the larvae feed on the roots of cruciferous vegetables, 
they cause little appreciable damage. 
The beetles are by no means confined in their injurious attacks to 
cabbage and other cole crops, since when they occur in unusual 
abundance they attack most forms of vegetable crops, including 
beans, peas, table and sugar beets, mustard, kale, and rape. As with 
1 PJiyUotreta pusilla Horn; family Chrysomelidae, order Coleoptera. 
2 This insect was under observation by the junior author (deceased) from 1909 until 1917, at Rocky Ford, 
Colo. 
1832°— 20- 1 
