Federally grown marijuana

Research chemist Zlatko Mehmedic, an official with the federal government’s Medical Research Project at the University of Mississippi, prepares to open a vault containing thousands of pot samples. (Brandon Dill / For the Los Angeles Times)

May 28, 2014 12 AM PT

What makes the cannabis here on the campus of the University of Mississippi unique is that it is grown, processed and sold by the federal government. The stockpile represents the only source of pot allowed for researchers who want to conduct FDA-approved tests on using marijuana for medical purposes.

Research chemist Zlatko Mehmedic shows a sample of marijuana confiscated by law enforcement now stored inside a vault at the University of Mississippi. The research lab is the only such facility in the United States under contract with the federal government. (Brandon Dill / For the Los Angeles Times )

Lanny Benjamin, supervisor of the Maynard W. Quimby Medicinal Plant Garden at the University of Mississippi, prepares peat pots for transplanting marijuana plants under the U.S. government’s Marijuana Research Project. (Brandon Dill / For the Los Angeles Times )

Dr. Mahmoud ElSohly has run the federal government’s Marijuana Research Project at the University of Mississippi since 1980. (Brandon Dill / For the Los Angeles Times )

Marijuana plant material fills a storage drum in a vault at the University of Mississippi. (Brandon Dill / For the Los Angeles Times )

Marijuana plants fill the grow room at University of Mississippi lab. (Brandon Dill / For the Los Angeles Times )