ORGANIZATION OF THE INITED STATES DEPARTMENT OF 

 AGRICULTURE. 



Secretary of Agriculture Henry C. Wallace. 



Assistant Seo'etary C W. Pugsley. 



Director of Scientific Woric E. D. Ball. 



Director of Regulatory Work 



Weather Bureau Charles F. Marvin, Chief. 



Bureau of Agricultural Economics Henby 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. 



„ ^ '^, . _. f Walter G. Campbell, 



Bureau of Chemistry ^ ^. ^, . ^ 



[ 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 Puhlic 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. 



Liirary Claribel It. Barnett, Librarian, 



States^ Relations Service A. C. Trve, Director. 



Federal Horticultural Board C. L. Marlatt, Chairman. 



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



Packers and Stockyards Administration ] Chester Morrill, 



Grain Future Trading Act Administration j A.ssistant to the Secretary. 



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



This bulletin is a contribution from 



Bureau of Plant Industry William A. Taylor, Chief. 



Dry-land Agriculture Investigations E. C. Chilcott, 



Agriculturist in Charge. 



28 



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