- Carl S. Scofield, Archibald Dixon Shamel, David A. Savage, David Leroy Yarnell, E. C. Tullis, Earl Dewey Mallison, Frederic Gordon Renner, Frederick Lovejoy Wellman, Hazel Edith Munsell, Horace Greeley Byers, Howard Barrett Richardson, Irvin Carl Feustel, Johnson Thatcher Sarvis, Joseph Heilman Shollenberger, Mason August Hein, Maxon Young Pillow, Myron Sallee Anderson, Norman Julian Wall, Percy Hoke Royster, T. D. Jarrell, Theodore Comstock Scheffer, Thornton Taft Munger, Walter Huber Meyer, William Henry Black, Alonzo Charles Cook, Carl Stone Pomeroy, Charles Lloyd Moon, E. A. Gorman, Grace Margaret DeVaney, James McKenzie Hankins, James Richard Quesenberry, John Carl Thysell, Ronald Floyd Luxford, Thomas L. W. Bailey, Alfred Leroy Baker, Carl Marcus Conrad, Elmer W. Knight, Fletcher Pearre Veitch, Mary Hanford Kennedy, Ralph Emerson Caryl, William Virgil Hukill
· 1937
- A. J. Pieters, Archibald Dixon Shamel, Benjamin Ralph Stauber, Chalmers Jackson King, Charles Sidney Leete, Charles Walter Collins, F. M. Grant, Fred Earl Keating, Frederick John Pritchard, Frederick Wulling Herbert, George McMillan Darrow, George Wright Hoffman, Harry Eugene Burke, Harvey John MacAloney, Hazel Katherine Stiebeling, Herman Meserve Johnson, Mary E. Sweeny, Neil E. Stevens, Orville Edward May, Oscar Roland Mathews, Perley Spaulding, Robert Claude Wright, Thomas Moore Whiteman, United States. Department of Agriculture, Walter Cochran Davis, Carl Stone Pomeroy, Charlotte Chatfield, Clarence Elbert Clement, George Fordyce Waldo, Harold Frederick Loomis, Horace Terhune Herrick, James Warren Hubbard, John Raymond Hansbrough, John Valentine Schaffner, Louis Henry Burgwald, Ruth Leah Morgan, Verner Ivan Clark, William Solomon Porte, Frank Nelson Harmon
· 1931
- William Kinsey Williams, Altus Lacy Quaintance, Archibald Dixon Shamel, Arthur Henry Senner, Arthur Maxwell Brunson, G. A. Collier, George Charles Husmann, Harold Glenn Meginnis, Harold Pearl Sheldon, Harvey Leroy Westover, Helmut Charles Diehl, John Robert Parker, Justus Watson Folsom, Kenneth Hayes Myers, Leonard Lee Harter, Orator Fuller Cook, Perkins Coville, Ralph Leroy Parshall, Raymond R. Pailthorp, Thomas William Heitz, Waldo Lee McAtee, Wallace Ashby, Archie Hubbard Glaves, Charles Ranger Enlow, Erval Jackson Newcomer, Frank G. Grimes, Harry August Schoth, Jacob Martin Lutz, James William Park, William John Zaumeyer, William Randolph Walton, Albert Lloyd Ryall, Arthur Truman Semple, Bennet Allen Porter
· 1931