IMPROVING DUCK MARSHES 



■•^WEED CONTROL 



By ALEX C. AAARTIN, RAY C. ERICKSON, 

 and JOHN H. STEENIS, V/ildlife Biologists 

 Bureau of Sport Fisheries and Wildlife 



CIRCULAR 19 -REVISED 



FISH AND WILDLIFE SERVICE, Arnie J. Suomela, Commissioner 



UNITED STATES DEPARTMENT OF THE INTERIOR 



Fred A. Seaton, Secretary 



UNITED STATES GOVERNMENT PRINTING OFFICE • WASHINGTON : 1957 



For sale by the Superintendent of Documents, United States Government Printing Office 

 Washington 25, D. C. : Price 25 cents 



