ORGANIZATION OF THE 
UNITED STATES DEPARTMENT OF AGRICULTURE. 
Seen tary of Agriculture Henry C. Wallace . 
Assistant Secretary C. W. Pugsle y. 
Director of Scientific Work E. D. Ball. 
Director of Regulatory Work 
Weather Bureau Charles F. Marvin, Chief. 
Bureau of Agricultural Economics Henry C. Taylor, Chief. 
Bureau of Animal Indust // John R. Mohler, Chief. 
Bureau of Plant Industry William A. Taylor, Chief. 
Fort st Sen ice W. B. Greeley, Chief. 
Bureau of Chemistry Walter G. Campbell, Acting Chiefs 
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 Edwin C. Powell, Acting Chief. 
Library Claribel R. Barnett, Librarian. 
Steites Relations Service A. C. True, Director. 
Federal Horticultural Board C. L. Marlatt, CJiairman. 
Insecticide and Fungicide Board J. K. Haywood, Chairman. 
PacJcers and Stockyards Administration 1 Chester Morrill, Assistant to the 
On, in Future Trading Act Administration J 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 Pathology . Haven Metcalf, Pathologist in\ 
Charge. 
20 
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PURCHASES AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 
