ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 
AGRICULTURE. 
Secretary of Agriculture Henry C. Wallace. 
Assistant Secretary r C. W. Pugsley. 
Director of Scientific Work E. D. Ball. 
Director of lUegulatory Work 
Weather Bureau Charles F. 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 PuUic Roads Thomas H. MacDonald, Chief. 
Fixed Nitrogen Research Laboratory F. G. Cottrell, Director. 
Division of Accounts and Dislmrsements A. Zappone, Chief. 
DitHsion of Publications John L, Cobbs, Jr., Chief. 
Library 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, Chairm^an. 
Packers and Stockyards Administration 1 Chester 'Mo^mjA., Assistant to the 
Grain Future Trading Act Administration J Secretary. 
Office of the Solicitor R. W. Williams, Solicitor. 
This bulletin is a contribution from the — j 
Bureau of Plant Industry William A. Taylor, Chief. \ 
Office of Dry-Land Agriculture InvestiA e. C. Chilcott, Agriculturist in \ 
gations. J charge. \ 
34 \ 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 
