UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1201 
Washington, D. C. ▼ March 19, 1924 
PLANTS TESTED FOR OR REPORTED TO POSSESS INSECT1CIDAL 
PROPERTIES. 1 
By N. E. McIndoo, Insect Physiologist, Fruit Insect Investigations, Bureau 
of Entomology, and A. F. Sievers, Chemical Biologist, Office of Drug, Poison- 
ous, and Oil Plant Investigations, Bureau of Plant Industry. 
CONTENTS. 
Page. 
Economic aspects of plant insecticides 1 
Methods used by the writers in preparing plants for insecticides 2 
Insects employed and methods of testing preparations against them 3 
Results obtained by the writers 5 
Discussion of the more important results obtained 5 
Comparative results discussed 10 
Discussion of the less important results obtained 21 
Catalogue of plants tested for or reported to possess insecticidal properties 24 
General summary 55'. 
Conclusions 54 
Literature cited 54 
Index of botanical and common names of plants catalogued 59 
ECONOMIC ASPECTS OF PLANT INSECTICIDES. 
The search for commercially valuable insecticides in the plant 
kingdom has two phases. The testing of the material to determine 
its effectiveness constitutes the first phase. After extensive labora- 
tory and field tests have proved it to have sufficient merit, it then be- 
comes necessary to determine the practicability of obtaining com- 
mercial quantities of the material and to make it available in 
proper form for insecticidal purposes. This constitutes the second 
phase. 
Several factors must be considered in determining the practical 
availability of a plant insecticide. Among these may be mentioned 
(1) habitat, whether foreign or domestic, and whether wild or culti- 
ir rhe Bureaus of Entomology and Plant Industry in 1915 began a cooperative project 
which included a careful study of the physiological effects of the plant insecticides and a 
search for new insecticides in the plant kingdom. At the outset a search was bei:un for 
plants which would furnish materials for efficient insecticides. This bulletin embodies 
most of the unpublished results of this study and also includes as complete a <a:alo£:ue 
as possible of all plants that have been tested for or reported to possess insecticidal prop- 
erties. Some of the plant material used in this work has come from foreign countries, but 
the majority of the samples are from the United States and its possessions. Man;. 
sons, chiefly employees of the United States Department of Agriculture, who are widely 
scattered over the world, have sent much of this material. The scientific and common 
names, families, and habitats of the plants discussed have been verified by Drs. ^. F. 
Blake, Frederick V. Coville, and W. E. Safford, all of the Bureau of Plant Industry. 
60635 °-24 1 1 
