﻿ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 

 AGRICULTURE. 



Secretary of Agriculture Henry C. Wallace. 



Assistant Secretary C. W. Pugsley. 



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 Industry John R v Mohler, Chief. 



Bureau of riant 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. 



Library Claribel R. Barnett, Libra- 

 rian. 



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 "(Chester Morrill, Assistant 



Grain Future Trading Act Administration J to the Secretary. 



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



This bulletin is a contribution from the — 



Bureau of Plant Industry William A. Taylor, Chief. 



Office of Dry-Land Agriculture Investigations- E. C Chilcott, Agriculturist 



in Charge. 

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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 

 COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 



