CONTRIBUTORS TO VOLUME I11
a. W. BURTON,Principal
Geneticist, U . S. Department of Agriculture, Georgia Coastal Plain Experiment Station, Tifton, Georgia.
H. J. HARPER, Professor of Soils, Oklahoma Agricultural and Mechanical College, Stillwater, Oklahoma.
J. A. MCMILLAN, Ministry of Agriculture and Fisheries, London, England. R. Q. PARKS,Assistmt Head, Division of Soil Management and Irm'gation, U . S. Department of Agriculture, Beltsville, Maryland.
R. F. REITEMEIER, Senior Soil Scientist, Division of Soil Management and Irrigation, U . 5.Department of Agriculture, Beltsville, Maryland.
R. W. SIMONSON, Assistant Chief, Division of Soil Survey, U . S. Department of Agriculture, Beltsville, Maryland. A. L. TAYLOR, Nematologist, U . 8.Department of Agrkulture, Beltsville, Mary land.
c!. J. WILLARD, Professor of Agronomy, T h e O h w State University, Columbus, Ohio. E. WINTERS, Head, Department of Agronomy, University of Tennessee, Knoxville, Tennessee.
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