- Charles Fletcher Rogers, Charles Richardson Jones, Colorado Agricultural Experiment Station, Don J. Tripp, Erwin Louis LeClerg, Ferris Milton Green, George Milton List, George Shealy Langford, Gunnar Sigesmund Klemmedson, Herbert Christian Hanson, Nellie Esther Goldthwaite, Raymond Terry Burdick, Whitney Coombs, William E. Code, William Parker Headden, Carl C. Gentry, Hazen Bascom Pingrey, Martin Reinholt
· 1929
- Benson H. Paul, C. A. Plaskett, Charles Nicholas Ainslie, Clarence Elbert Clement, Dorothy Nickerson, Edward Mackay Chace, Emilio Pepe Meinecke, Franklin Thomas Cowan, George G. Ainslie, James Johnson, James Stanley Mathewson, John A. Newlin, Joseph Hubert Priestley, Laurence Victor Teesdale, Lewis Bertie Olmstead, Lorraine Joseph Markwardt, Louis Guy Michael, Oliver I. Snapp, Ralph Wylie Frey, Raphael Zon, Ruric Creegan Roark, Samuel Trask Dana, Whitney Coombs, William Gustavus Wahlenberg, William White, C. S. Trimble, H. S. Swingle, Calvin Grant Church, Charles F. Swingle, Ira Doup Clarke, John Martin Gahagan, Lyle Thomas Alexander, R. D. Garver, R. T. Cotton, Harry Lawrence Wilson, Howard E. Middleton
· 1930