STANDISH — Some things were missing from the dining hall when students returned to Saint Joseph's College this month.

The trays had disappeared. And so had a good deal of the food waste that accompanied them.

In the past, about 16 tons of uneaten food scraped off plates each year went into the waste stream and ultimately was incinerated. Stuart Leckie, general manager of Bon Apptit, the company that runs the dining service, hopes removing the trays will help cut waste in half and save water and electricity used for washing.

The idea: Diners will make their choices more carefully when they can't just load up a tray with everything that catches their fancy. There's still no limit on how much students are allowed to eat, but they'll have to make additional trips if they want more food than they can carry.

"They used to come in, grab a tray, grab something from the grill, grab something from the hot line, get a couple of drinks, put a couple of cookies on their tray. Then they'd sit down," Leckie said. "We noticed huge amounts of things coming back. Half a wrap, half a burger."

The move is just one way college dining services in Maine are trying to make their operations more environmentally friendly. In addition to purchasing food locally, they have adopted practices such as sending food waste to pig farms, composting scraps, buying in bulk and limiting seafood to species that are not vulnerable to overfishing.

The push for such practices is coming from a number of directions -- students, the school and the food service companies themselves, said Keith Brady, director of dining for the University of Southern Maine, which sends waste to a pig farm.

"If it's part of their goals, it's part of our goals," said Brady, who works for the company Aramark.

The decision to go trayless at Saint Joseph's came after an experiment found that waste dropped on trayless days. Since the change, Leckie said, he has noticed less plate scraping and that desserts aren't going as fast. He thinks diners tend to get one course at a time and that they feel satisfied before they get to dessert.

"A lot of times you'd tend to take more food than you need," said sophomore Nico Tarquinio. "I used to take way too much food and probably eat too much."

Jeremy Gervais, a sophomore, said removal of trays was a good health choice. He didn't mind having to make a couple of trips to get all the components of a recent lunch. Beef barley soup, shrimp carbonara pasta and red potato from three stations went onto one plate in one trip and silverware and a drink went on the second.

"If I wanted to get something else, I'd just go up again," he said, while noting that it wasn't worth the wait for some items during the busiest times. "If you want something at the grill, forget it on the second pass."

Chris Leger, a junior, was among the students who noticed that less food went into the trash.

"Nobody wastes as much food," he said.

Freshman John Swasey approves of the trayless approach for another reason.

"It's more like being at home. It's more comfortable," he said.

But Steve Gorson, a junior, thought the change made meals less convenient. His trays would normally carry two or three glasses and a couple of plates of food -- not because he was getting large quantities, he said, but because they were items such as pasta and a sandwich that shouldn't run together.

"It's a lot more difficult to get more than one plate and one drink," he said. "You still get all you need. It just takes longer."

At Colby College, there is one-third less waste on trayless Thursdays, said Varun Avasthi, director of dining services at the college and Maine district manager for Sodexho, which also handles dining at Maine Maritime Academy and the University of New England. Waste is composted rather than run through garbage disposals, a practice he said would lead to 80 tons of food going into...