- 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
- Charles Adolph Weigel, Charles John Stauber, D. C. Parman, D. W. Jones, David Griffiths, Don Inskeep Skidmore, Elmer Ottis Wooton, Erastus Newton Bates, Ernst H. Wiecking, James A. Holden, John Chambers McDowell, John Clay Overpeck, Kelsey Beeler Gardner, Lloyd Stanley Tenny, Lucia McCulloch, Madge Janet Reese, Ora Stanley Fisher, Orator Fuller Cook, Raphael Zon, United States. Department of Agriculture, Ward Shepard, William Alfred Schoenfeld, William Edward Wintermeyer, D. J. Caffrey, Duncan Stuart, George P. Bodnar, William Norwood Sparhawk, R. R. Graves
· 1927
- Thomas S. Buchanan, Constantin Constantinovich Nikiforoff, Dwight McBryde Simpson, Dwight Moore DeLong, Frank M. Eaton, G. J. Haeussler, G. R. Free, George Wright Hoffman, Gustav A. Wiebe, Harold Andrus Jaynes, Harry Ardell Allard, Henry Hopp, J. I. Lauritzen, James Robert Dawson, Joseph Stuart Caldwell, Kenneth Thurman Williams, Lawrence Zeleny, Loyd L. Stitt, Marshall Weddell Stone, Raymond Peter Christensen, Robert Merton Walsh, Ruth Elmquist Rogers, Theodore Roosevelt Gardner, Thomas Charles Chadwick, Wilbur Tibbils Pentzer, Caroline L. Adams, Charles A. Fort, David Victor Kopland, E. K. Bynum, George Henry Englerth, Helen Garrison Wheeler, James Stewart Wiant, Lawrence Bemis Parker, Morris Harvey Neustadt, Philip Russell Cowan, R. R. Whetstone, Ronald Lester Mighell, Roy Drummond McCallum, Samuel Palkin, Wightman Wells Garner, G. M. Stone, Harry Humfeld, John Henry MacGillivray, Lucille Reinbach-Welch, Miles Stratford Mayhugh, R. R. Graves, R. T. Balch
· 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
- Ralph U. Cotter, C. A. Magoon, Charles Brooks, Charles Faye Sarle, Charles Otis Johnston, Curtis Paul Clausen, Elmer Ottis Wooton, Floyd Franklin Smith, Fred W. Miller, Harvey Leroy Westover, Howard E. Middleton, Irvin Cecil Brown, Irvine Theodore Haig, James Thorp, Lester Henry Reineke, Lyle Thomas Alexander, Millard Peck, Orator Fuller Cook, Ronald Floyd Luxford, Samuel Augustus Jones, V. L. Wildermuth, Walter Chapin Holmes, William Hobson Rowe, William John Nolan, Willis James Nolan, Bernard Frank, Charles W. Culpepper, Clarence Sheldon Slater, Donald Bruce, Edwin Butterworth Mains, Elmer Valentine Walter, Horace Greeley Byers, John Thomas Scanlan, Johnson Thatcher Sarvis, Lorraine Joseph Markwardt, Paul A. Berry, R. R. Graves, Theodore Roosevelt Gardner, Anis Rae Peterson, Kaku Sato, Leroy Moomaw, Paul Axel Clarence Eke, George W. Morgan, John Carl Thysell, M. A. Bell
· 1932
- Alice Linna Allen Bailey Nightingale, Charles Abel Bennett, Charles Brooks, Charles William Mann, Claude Hope, Dean Humboldt Rose, Dow Dewey Porter, Eloise Blaine Cram, Francis Leo Gerdes, Frederick William Metzger, George W. Barber, Harry Nelson Vinall, Henry Miner Eakin, Irvin Cecil Brown, Katherine Melvina Downey, Norman Julian Wall, Paul Lewis Harding, R. W. Leukel, Robert H. Weidman, Stephen Harold Hastings, Thompson Elwyn Woodward, Verne Lester Harper, William Jeter Phillips, Chalmers Jackson King, Charles Lincoln Powell, Cyril Oliver Bratley, E. A. Gorman, Glen Blaine Ramsey, Horace Greeley Byers, J. C. Stephens, Lenthall Wyman, Ralph P. Hotis, Warren W. Maines, William Cecil Cooper, John Holmes Martin, Lacy Porter McColloch, Orlan Parker, R. R. Graves
· 1936