Make no mistake: Penguin costumes are not recyclable.

In a sample conducted Thursday morning of University of Wisconsin students' recycling, an old penguin costume was one of many nonrecyclable items found within the green bins.

"Don't confuse the fact that since there are recycling symbols on every piece of plastic that it can be recycled," said recycling coordinator George Dreckmann, who conducted the sample. "If somebody isn't making something out of it, it can't be recycled."

According to Dreckmann, 15 percent of the materials they collected from students' recycling bins was actually trash. That is almost twice as much as the average amount for the city as a whole, which is around 8.3 percent.

"One of the things that helps account for that was there were six bags of garbage in the recycling," Dreckmann said. "The first lesson is you have to put things in the right bin."

Dreckmann said that even bags half-filled with trash would render the whole bag non-recyclable.

One of the most common non-recyclable items he found in students' recycling carts was plastic film, such as grocery bags and food wrappers. Fast food containers, pizza boxes and Styrofoam were other popular mistakes.

"The only thing from fast food restaurants that you can recycle is the bag; the rest is all garbage," Dreckmann said.

He also clarified the top of a pizza box is usually the only salvageable part, and even then only if it has been ripped off and doesn't show signs of food.

Bottles and jars may also be recycled, but only if thoroughly rinsed out.

"If they're not rinsed out right away, throw them out," Dreckmann said.

Despite the sample's results, however, senior Danny Wedel said he is careful in sorting his recycling. Wedel has lived in a house near campus for the past three years.

"We try to keep it as separated as possible," Wedel said. "Most people probably aren't as picky as I am, but I try to filter through it."

However, even Weber, a careful recycler on campus, said he didn't know only the tops of pizza boxes are recyclable, and has previously folded up the entire box for recycling.

Senior Jamie Shah also said she made an effort to recycle carefully when she lived in a house her junior year. She and her roommates went as far as posting a chart over their garbage that spelled out what could be recycled and what was trash.

"We even separated the number of recycling," Shah said, explaining that she would sort the items by the number on the label. "It really didn't feel like we were doing any extra work."

When students are not meticulous in choosing what to recycle, however, Dreckmann said the city has to spend more money to sort the garbage from the recyclables.

"The things put in recycling that can't be recycled have to get sorted before they go to the landfill," Dreckmann said.

Dreckmann also advised students to make sure that when they put their recycling carts out for pick-up, the openings are facing the street.