The Wagbags (WAG stands for Waste Alleviation and Gelling) are manufactured by Phillips Environmental Products in Montana and have been adopted by agencies including the Pentagon and the Federal Emergency Management Agency, said the company’s president, Bill Phillips.

Their appearance in places like the John Muir Wilderness or the Grand Canyon is one more indication that park stewards want visitors to take responsibility for themselves. For several years, the National Park Service has required visitors who need helicopter rescues to help pay for the cost of sending in the copter.

Hikers on the Mount Whitney trail, in most cases, willingly shoulder the burden of the new sanitation regimen.

“If I’ve got to do it, I’ve got to do it,” said Scott Whitten of Danville, Calif., about halfway up the trail. “I’m not a big fan of it.”

So far this year, more than 4,500 pounds of waste in Wagbags has been deposited in receptacles at the Whitney Portal trail head, all of it headed for landfills, where the bags are designed to biodegrade over six to nine months.

“I don’t mind it,” said Marilyn Nelson, 64, who had just finished her first hike to Trail Camp, at 12,000 feet the highest camp below the summit of Mount Whitney on the eastern approach. “There are so many indignities on the trail anyway. And people do that all the time with their dogs in the city.”

But while her son, Brendan Nelson, 43, who works in television promotion in Los Angeles, accepted the need for the change, he was still nostalgic for the Trail Camp outhouse that was dismantled this year.