ORGANIZATION OF THE UNITED STATES DEPARTMENT OF AGRICULTURE 

 WHEN THIS PUBLICATION WAS LAST PRINTED 



Secretary of Agriculture Henry A.Wallace. 



Under Secretary Rexford G. Tug well. 



Assistant Secretary M. L. Wilson. 



Director of Extension Work C. W. Warburton. 



Director of Finance W. A. Jump. 



Director of Information M. S.Eisenhower. 



Director of Personnel W. W. Stockberger. 



Director of Research James T. Jardine. 



Solicitor Mastin G. White: 



Agricultural Adjustment Administration H. R. Tolley, Administrator. 



Bureau of Agricultural Economics A. G. Black, Chief. 



Bureau of Agricultural Engineering S. H. McCrory, Chief. 



Bureau of Animal Industry John R. Mohler, Chief. 



Bureau of Biological Survey Ira N. Gabrielson, Chief. 



Bureau of Chemistry and Soils Henry G. Knight, Chief. 



Commodity Exchange Administration J. W. T. Duvel, Chief. 



Bureau of Dairy Industry O. E. Reed, Chief. 



Bureau of Entomology and Plant Quarantine. Lee A. Strong, Chief. 



Office of Experiment Stations James T. Jardine, Chief. 



Food and Drug Administration Walter G. Campbell, Chief. 



Forest Service Ferdinand A. Silcox, Chief. 



Bureau of Home Economics Louise Stanley, Chief. 



Library Claribel R. Barnett, Librarian. 



Bureau of Plant Industry Frederick D. Richey, Chief. 



Bureau of Public Roads Thomas H. MacDonald, Chief. 



Soil Conservation Service H. H. Bennett, Chief. 



Weather Bureau Willis R. Gregg, Chief. 



This circular is a contribution from 



Bureau of Plant Industry Frederick D. Richey, Chief. 



Division of Dry Land Agriculture C. E. L>elghty, Principal Agronomist, 



in Charge. 

 48 



U. S. GOVERNMENT PRINTING OFFICE: 1937 



