Back in the 1980s and early 1990s, it was an informal tradition for fans to roll oranges on the football field to celebrate a Big Eight championship win and entry into the Orange Bowl.

Now, University of Colorado officials say to leave those oranges at home. They are among items considered contraband in the stadium because they can be injected with vodka or become a dangerous projectile, said campus spokesman Bronson Hilliard.

CU officials Wednesday released the game-day rules for fans attending Sunday's rivalry game between CU and Colorado State University. Banned materials include alcoholic beverages, cans, glass bottles, ice chests and liquid containers that are a gallon or more in size.

In addition to the ban on alcohol in the stadium, whole fruit, marshmallows and other items that could potentially injure people if thrown also are banned.

"We want a safe experience for fans," Hilliard said.

University officials say fans in the past have stuck batteries, quarters or other hard items in marshmallows and thrown them on the field.

"Some throw the marshmallows to be cute, but other fans have placed objects inside them and hurled them at officials for bad calls," Hilliard said.

Police and security personnel working at Folsom Field will check for alcohol and other banned articles at all entry gates. An "amnesty" arrangement will allow people entering the stadium to throw out the banned items before heading into the game.

"If you're caught once you've come inside, you're subject to ejection," said CU Police Cmdr. Brad Wiesley.

Safety officials are hoping the marshmallow tossing was a fad that has died out. Last year, there were few marshmallow incidents.

"I don't think we remember seeing any big marshmallow fights," he said.

Visibly intoxicated people will be denied admission to the stadium or ejected. Underage people caught with alcohol also will be ejected and issued "minor in possession" tickets.

CU students who are cited for alcohol offenses also face judicial action by the university.

Fans ejected from a game may be denied access to future games and their tickets may be confiscated, depending on the severity of the infraction.

A hotline will be available to fans again this year to report unruly behavior, at 303-735-BUFF (2833).

Contact Camera Staff Writer Brittany Anas at 303- 473-1132 or anasb@dailycamera.com.