ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 
AGRICULTURE. 
Secretary of Agriculture Henry C. Wallace. 
Assistant Secretary C. W. Ptjgsley. 
Director of Scientific Work E. D. Ball. 
Birector of Regulatory Work . 
Weather Bureau Charles F. Marvin, Chief. 
Bureau of Agricultural Economics Henry O. Taybor, Chief. 
Bureau of Animal Industry John R. Mohlhr, 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 Melton 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, Librarian. 
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 1 Chester Morrill, Assistant to t he 
Grain Future Trading Act Administration— J Secretary. 
Office of the Solicitor— R. W. Williams, solicitor. 
This Bulletin is a contribution from the — 
Forest Service William B. Greeley, Forester. 
Branch of Research Eaele H. Clapp, Asst. Forester. 
Forest Products Laboratory Carlile P. Winslow, Director. 
Section of Timber Physics Rolf Thelen, in charge. 
