ORGANIZATION OF THE UNITED STATES tO a OF 
AGRICULTURE. 
secretary_of Agriculture. HENRY C. WALLACE. 
Assistant Secretary_.______ Rade Tita ene Bs De C. W. PUGSLEY. 
Director of Scientific Work___._________=. BH. DisB AEE: 
Director of Regulatory Work______-__--_- 
Weather Bureq2 a. 2 ea ee ee CHARLES W. Marvin, Chief. 
Bureau of Agricultural Economics_______- Henry C. Taytor, Chief. 
Bureau of Animal Industry_____________=. JOHN R. MOoHIER, Chief. 
BUTCOUAOfeRlLOnt INGQUStTY eee WILLIAM A. TAytor, Chief. 
OT CSE IS CHUL CE mee ee a eae Ns etd ee W. B. GREELEY, Chief. 
BUT COMTOL SC ILCIRUS UTA = eek are ie ee WALTER G. CAMPBELL, Acting Chief. 
BUreai Of SOUS a ee Pee ee MILTton WHITNEY, Chief. 
BUuredi-Of Entomology =. = ae L. O. HowaArp, Chief. 
Bureau of Biological Survey________--___. EK. W. NEtson, Chief. 
Bureau Of Puc ROCs] 2 ae ee THomAS H. MACDONALD, Chief. 
Fized-Nitrogen Research Laboratory_____- F. G. Cottretyi, Direcior. 
Division of Accounts and Disbursements__. A. ZAPPONE, Chief. 
Diision- of Publications_— = = JOHN L. Copgss, Jr., Chief. 
BH OY HO PU [ee SRE a ee oe cr ag On eee SIS CLARIBEL R. BARNETT, Librarian. 
States Relations Services {= ee A. C. Tru, Director. 
Federal Horticultural Board_____________ C. L. MARLATT, Chairman. 
Insecticide and Fungicide Board_________- J. K. HAywoop, Chairman. 
Packers and Stockyards ee eae Morrit1, Asistant to the 
Grain Future-Trading Act Administration_- Secretary. 
Office of the Solicitor R. W. WILLIAMS, Solicitor. 
This bulletin is a contribution from— 
BUC. Of Pelant TNQUSIY = eee Witiiam A. TaAytor, Chief. 
Office of Investigations in Forest Pa- HaveEN MetcauLr, Pathologist in 
thology. Charge. 
BY 
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OF THIS PUBLICATION MAY BE PROCURED FROM 
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GOVERNMENT PRINTING OFFICE 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.—PUB. RES. 57, APPROVED MAY 11, 1922 
