- S1991-1992 #29: United States Forest Service/James L. Boyton (May 21, 1992–August 2, 1995)195 objects
- S1997-1998 #8: California State University, Chico/Nette Martinez (March 23, 1998–May 29, 2008)5 objects
- S2005-2006 #6: Integrative Biology Department (UC Berkeley)/Timothy D. White (October 12, 2005–November 20, 2020)4 objects
- S1984-1985 #18: Sonoma State University (November 1, 1984–March 1986)3 objects
- S1975-1976 #10: Smithsonian Institution (September 2, 1975–November 10, 1975)2 objects
- S2002-2003 #14: Pacific Legacy, Inc./Thomas L. Jackson (February 21, 2003–February 21, 2004)2 objects
- S1982-1983 #39: University of California, Davis (April 11, 1983–July 21, 1986)1 objects
- S1987-1988 #41: University of North Carolina/Geirge R. Holcomb (March 29, 1988–July 6, 1990)1 objects
- S1991-1992 #16: University of Utah/James F. O'Connell (November 25, 1991–July 30, 1992)1 objects
- S1993-1994 #21: California State University, Chico/Turhon Murad (July 12, 1994–May 4, 1998)1 objects
- S2001-2002 #10: Integrative Biology Department (UC Berkeley)/Timothy D. White (November 30, 2001–November 30, 2002)1 objects
- S2009-2010 #8: Seed Lab, Plant Pest Diagnostics Center (CA Dept. of Food and Agriculture)/Deborah Meyer (February 12, 2010–July 30, 2010)1 objects