﻿ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 

 AGRICULTURE. 



Secretary of Agriculture Henry C. Waixace. 



Assistant Secretary C. W. Pugsley. 



Director of Scientific Work i. E. D. Ball. 



Direotor of Regulatory Work 



Weather Bureau Chaeles W. Marvin, Chief. 



Bureau of Agricultural Economics Henry C. Taylor, Chief. 



Bureau of Animal Industry John R. Mohler, Chief. 



Bureau of Plant Industry William A. Taylor, Chief. 



Forest Service W. B. Greeley, Chief. 



Bureau of Chemistry Walter G. Campbell, Acting Chief. 



Bureau of Soils Milton Whitney, Chief. 



Bureau of Entomology L. O. Howard, Chief. 



Bureau of Biological Survey E. W. Nelson, Chief. 



Bureau of Public Roads Thomas H. MacDonald, Chief. 



Fixed-Nitrogen Research Laboratory F. G. Cottrell, Director. 



Division of Accounts and Disbursements A. Zappone, Chief. 



Division of Publications John L. Cobbs, Jr., Chief. 



IAbrary , Claribel R. Barnett, Librarian. 



States Relations Service A. C. True, Director. 



Federal Horticultural Board C. L. Marlatt, Chairman. 



Insecticide and Fungicide Board J. K. Haywood, Chairman. 



Packers and Stockyards Administration "I Chester Morrill, Asistant to the 



Grain Future-Trading Act Adm in istration—l Secretary. 



Office of the Solicitor R- W. Williams, Solicitor. 



This bulletin is a contribution from — 



Bureau of Plant Industry William A. Taylor, Chief. 



Office of Investigations in Forest Pa- Haven Metcalf, Pathologist in 

 thology. Charge. 



52 



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