- Charles A. Fort, Charles Chase Hill, David Francis Costello, David Irving Blumenstock, Doys Andrew Shorb, Elmer R. Roth, Ethelbert Lee Langsford, Everett Elmer Wehr, Frank M. Eaton, Horace Preston Lanchester, Irvin Carl Feustel, Leander D. Howell, Lucy Maclay Alexander, Lyle Thomas Alexander, Mark Hughlin Haller, Milton Henry Fohrman, Robert Edgar Worthington, Roy Hyer Canfield, Stafford Coleman Happ, Thomas Randall Carson Wilson, United States. Bureau of Plant Industry, Vernon Webster Johnson, William Gustavus Wahlenberg, Bailey Sleeth, Ben Hur Thibodeaux, Gordon Rittenhouse, Horace Greeley Byers, John Stuart Pinckney, L. V. Wilcox, Nancy Griswold Clark, Nelson McKaig, Paul Lewis Harding, R. R. Graves, Raymond Price, Sidney Henderson, Smith Winford Greene, Edgar John Udine, Gilbert Colfax Dobson, Glen Edgington, Hiram Richard Reed, James Hayes Marshall
· 1940
- Arnold Kent Balls, Earl W. McComas, Erastus Newton Bates, Hamilton Paul Traub, Jacob Allen Clark, Mark Hughlin Haller, Ralph Corbin Hall, Walter Jay Hall, William Alvin Douglas, William Doyle Reed, Harold Edwin Stevens, James Edwin Comfort, Jesse Wilburn Ingram, John Paul Vinzant, Karl Spangler Quisenberry, Marian William Hazen, T. Ralph Robinson
· 1941
- F. W. Poos, Arthur Charles Dillman, Barry Cutler Park, Bion Tolman, C. A. Matthews, C. J. Babcock, Earl W. McComas, Ernst Artschwager, Francis Eugene Clark, Francis Raymond Lawson, Geoffrey Seddon Shepherd, Harley A. Daniel, Irvin Cecil Brown, James Ellsworth Kraus, Jay Laurence Lush, John Clifford Elmore, Kenneth Barbee McKinney, Kenneth Pickett Davis, Mark Hughlin Haller, R. A. Blanchard, R. S. Holmes, R. W. Leukel, William Henry Black, Harry M. Elwell, A. F. Howland, Arthur Eugene Molln, Besse B. Day, James Russell Douglas, James Thorp, John Holmes Martin, Nancy Harper Wheeler, R. L. Piemeisel, Ruth C. McGuire, Turner Harcourt Hopper, Walter Whittier Swett, Williamson Edward Hearn, Maurice B. Cox, Byron Lester Southwell, R. R. Graves
· 1944
- Edgar John Udine, Edmund Lambert, Edward Mackay Chace, Emil George Boerner, F. L. Duley, Franklin Arthur Coffman, George Emil Gaus, Gerard Dikmans, Harold Robert Hochmuth, John Stuart Pinckney, Joseph Benjamin Shepherd, M. A. Yothers, Mark Hughlin Haller, Robert Hale Nelson, Roland McKee, Russell Rutherford Whitten, United States. Department of Agriculture, Victor Leo Stedronsky, W. A. Douglas, W. G. Bradley, William John Reid, William Solomon Porte, Carroll Clayton Cassil, Charles Scott Shaw, Dean Humboldt Rose, Earl Raymond Franklin, Harry August Schoth, Harry Bruce Walker, Latimer Ludwig Kelly, Paul B. Allen, Rhea Emerson Stitt, Thomas Laffin Baggette, Thompson Elwyn Woodward, William Alexander Noel, Arvid John Johnson, Marion Clawson, Paul Lewis Harding, Vinnie Arah Pease, Waldo Harold Kliever
· 1941