ORGANIZATION OF THE 
UNITED STATES DEPARTMENT OF AGRICULTURE. 
Sea * tary of Agriculture Henry G. "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 0. 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 af 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. 
Fired Nitrog< n Research Laboratory F. G. Cottrell, Director. 
Division of Accounts and Disbursements A. Zappone, Chief. 
Division of Publications Edwin C. Powell, Acting Chief. 
Library Claribel R . Barnett, Librarian. 
States Relations Service A. C. True, Director. 
Fedt rat Horticultural Board C. L. Marlatt, Chairman. 
iicide and Fungicidi Board .... J. K. Haywood. Chairman* 
s and Stockyards Administration [Chester Morrill, Assistant to the 
Grain Future Trading Ad Administration j Secretary. 
Office of the Solicitor R. W. Williams, Solicitor. 
This bulletin is a contribution from — 
Bureau of Plant Industry William A. Taylor. Chief. 
Office of All-ali and Drought Resistant Thomas II. Kearney, Physiologist 
Plant Investigations. in Charge. 
53 
' 
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OF THIS PUBLICATION MAY BE PROCURED FROM 
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GOVERNMENT FIUXTING OFFICE 
WASHINGTON, D. C. 
AT 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 
