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UNITED STATES DEPARTMENT OF AGRICULTURE 
In Cooperation with the University 
of Wisconsin and the Wisconsin Department of Agriculture 
DEPARTMENT BULLETIN No. 1316 
Washington, D. C. 
April 1925 
SOME EFFECTS OF. SODIUM ARSENITE WHEN USED TO KILL THE 
COMMON BARBERRY 
By E. R. Schulz, Agent, and Noel F. Thompson, Associate Pathologist, Office 
of Cereal Investigations, Bureau of Plant Industry 1 
CONTENTS 
Page 
Introduction 1 
Historical review 2 
Arsenic as a weed killer, 2 
Toxic and stimulating effects on 
plants 3 
Toxic effects on animals 5 
Method used in arsenic analysis 6 
Description of apparatus 6 
Preparation of sample 6 
Procedure of analysis 7 
Page 
Experimental results 7 
Killing concentrations of arseni- 
cal solutions 7 
Absorption of arsenic by plant 
tissues 10 
Rate of leaching of sodium ar- 
senite from soils 12 
Sodium arsenite and farm ani- 
mals 15 
Discussion 14 
Summary 15 
Literature cited 16 
INTRODUCTION 
For six years the United States Department of Agriculture, with 
the assistance of State and other agencies, has been waging a war 
on the common barberry in 13 of the Xorth-Central States of the 
Union. Millions of bushes have been located, and their extermina- 
tion has followed as rapidly as possible. The common barberry 
was not native in this area but had been extensively planted, and 
many escaped barberries had developed from seeds produced on the 
planted bushes and spread by birds and cattle. 
Extermination of the plants by digging was soon found to be not 
only difficult but very expensive. This was especially true of those 
escaped bushes that had become established in stony ground or with 
their roots intertwined with those of large trees. When such 
bushes were dug, even small fragments of the roots left in the ground 
would usually sprout, necessitating not only a second or third visit 
to the place but often much additional work. An economical and 
effective method of killing these bushes therefore was sought, and 
many different chemicals were tried on small bushes, first in the 
1 The writers wish to acknowledge their indebtedness to Dr. W. E. Tottingham for 
suggestions and criticisms and to H. B. Parmele for assistance in analytical work, 
15691°— 2o 1 
