- Arnold L. Nelson, Arvid John Johnson, Bradford Knapp, Charles Ellsworth Gage, Curtis Benton, Cyril Oliver Bratley, D. F. Fisher, E. H. Siegler, Edmund Lambert, Floyd Franklin Smith, Forrest Vern Owen, Frederick James Stevenson, George Arceneaux, George McMillan Darrow, Hazel Katherine Stiebeling, James Herbert Beattie, Loyd William Brannon, Robert Roland Farrar, Van E. Romney, Waldo Lee McAtee, Wayne Melville Bever, William Henry Burrows, William Ogilvie Fraser, William Taylor Miller, United States. Department of Agriculture, Arthur Steele Mason, Charles Frederick Clark, Don Juan Slater, Esther Funnell Phipard, Francis Munger, Harry Humfeld, Howard W. Johnson, I. E. Stokes, Jacob Martin Lutz, Joseph Patrick Quinn, Thomas Laffin Baggette, Victor Rickman Boswell, Wesley Pillsbury Flint, Woodrow Wilson Bailey, John McDowell McCown, Lloyd E. Smith, Talbott Elson Clarke
· 1939
- Albert Rudolf Leding, Alexander Campbell Martin, Arnon Lewis Mehring, Arthur Henry Senner, Arthur T. Sweet, Auton William Skuderna, Benjamin Ralph Stauber, C. C. Plummer, C. H. Hadley, Chalmers Jackson King, Curtis May, Curtis Paul Clausen, David A. Savage, David Griffiths, Ernest Victor Abbott, Floyd Franklin Smith, Frederick Charles Lincoln, George Arceneaux, Glenn Gardner Hahn, Harold F. Scholz, Harold Glenn Meginnis, Harold Hall McKinney, Harry Baker Humphrey, J. Clark Salyer, James Fitton Couch, James Herbert Beattie, Jenkin William Jones, John Morrison Cooper, John Robert Parker, Kurt Walter Franke, Lewis Alexander Hurst, Mayne Reid Coe, Orator Fuller Cook, Paul George Russell, Paul Mehl, Paul William Miller, R. A. Blanchard, R. T. Balch, Ralph P. Hotis, Robert J. Sim, Robert Max Merrill, Theodore Bergen Manny, United States. Division of Silvics, Walter Ernest Fleming, Wilbur Clifford Edmundson, Wilbur Magruder Hurst, Wilfred Wickes Ballard, William Middleton, United States. Department of Agriculture, Asa Young Willis, Avis Jenkin Peterson, Claude Hope, Frederick William Metzger, I. E. Stokes, Ira Myron Hawley, J. I. Lauritzen, James Robert McCalmont, John Adam Stoehr, John Walter Taylor, Ralph Brownson Bisland, Victor Rickman Boswell, Walter Raymond Humphries, Wayne Crocker Nason, William Ernest Stone, Charles Conrad Krumbhaar, E. E. Hall, Max Raymond Osburn, Roland McKee
· 1933
- Alan D'Yarmett Freas, Albert Wade Brant, Alice Louise Robert, Arthur Charles Dillman, Coit Alfred Suneson, George Arceneaux, Harold Morrison, Henry Thomas Converse, Moses Naphtali Levine, Philip Luginbill, R. E. Wagner, Richard J. Foote, Sidney J. Armore, Verz Rogers Goddard, William Walter Donnan, Alfred W. Otte, George B. Bradshaw, Harland Stevens, Henry Raymond Painter, Herbert G. Wiseman, John W. Klein, L. P. Hebert, Magnus Leonard Selbo, Mary Williams Marshall, William John Cherewick, Gilbert Chin, L. C. Mayeux, Malcolm Clough
· 1953