BOULDER, Colo. -- University of Colorado at Boulder officials are hoping the stench of fish fertilizer will keep the air clear over campus by discouraging people from showing up for the "4/20" smokeout.
Crews were out early Friday spraying grassy areas with the stinky stuff as a deterrent.
April 20th, referred to as "4/20," is typically a big day for marijuana smoke-outs.
Earlier, a district court judge upheld the school's decision to only allow students on campus Friday.
Chancellor Phil Distefano says, "Because of the disruption (last year), we took this bold move."
Six non-CU students had filed a last-minute, emergency injunction to keep the campus open. After close to four hours of testimony, a judge ruled in favor of the school.
"It clearly does not speak to constitutional free speech," says Timothy Tipton, one of the six to file the suit.
Friday, students may be asked to show identification. All other visitors will most likely be asked to stay away.
In 2011, more than 10,000 people descended on the Boulder campus to partake in the event.
CU says it cost more than $50,000 for cleanup and security.
A CU spokesperson told the Boulder City Council it is not a statement for or against marijuana, but the event has grown too large and causes too much disruption for students and staff.
Students FOX31 Denver spoke to say they support the ban.