Mountains of paper are dumped every day into recycling bins in homes, offices, factories and schools. Use that to make toilet paper, activists suggest.

Time to roll off the big number: If each American family would buy one recycled roll just one time, it would save 400,000 trees, allegedly.

Greenpeace, the Natural Resources Defense Council and other environmental groups have pushed manufacturers such as Kimberly-Clark (Cottonelle) and Procter & Gamble (Charmin) to stop using wood from virgin forests to make tissue products, asking: Why should Americans use luxurious toilet paper made from old-growth trees when much of the world gets by with a far more basic and often recycled product?

The problem, though, is that each time paper is shredded during the recycling process, its fibers get shorter. The shorter the fiber, the less soft the tissue. And Americans, though saying in surveys that they embrace green initiatives, also say they don't want to sacrifice comfort.

"The truth is that other parts of the world are further along in using recycled content," said Kay Jackson, spokeswoman for Kimberly-Clark. "The American consumer still wants softness, and they are speaking with their pocketbooks."

Pulling back in a competitive market is asking a lot, manufacturers say. They also point out that only 5 percent of forest-industry production goes toward toilet paper.

Darby Hoover, a senior resource specialist with the Natural Resources Defense Council, understands the pressure of customer demand but wonders: Do we really need toilet paper to be as soft as it can be or do we need it just soft enough?

Environmentalists say that other countries — particularly in South America, Africa and Asia — seem to be OK with "soft enough."

Greenpeace has come up with a "toilet paper guide" for consumers on which brands are environmentally friendly. The criteria are recycled content and the use of chlorine bleaches, chlorine having been identified with its own ecological ills.

"When you're doing your grocery shopping or just stopping by the corner store to grab a roll of toilet paper, make an informed decision as both a consumer and someone concerned about the world's ancient forests," the guide says.

Probably no surprise that brands with names such as Green Forest, 365, Earth Friendly, Natural Value and Seventh Generation scored the highest on the Greenpeace scale.

Bringing up the rear: Charmin, Cottonelle, Angel Soft, and, of course, Quilted Northern, which sounds thick enough to keep someone warm on a cold night in Minnesota.

Some manufacturers say they are taking steps to become more environmentally friendly. More wood is from sustainable forests, and they are trying to up their recycled content.

Critics, though, such as NRDC senior scientist Allen Hershkowitz, point out that many of the reforms apply only to the professional market — schools, business, theaters, stadiums and restaurants.

Home is another tissue. There, many Americans still insist on the pillowy soft of virgin fibers.

Lisa Jester at P&G said the company is committed to the environment and takes seriously its responsibility to help ensure sustainability of the world's forest resources.

"All the fiber we use comes from sources that practice sustainable forestry," she said. "That means that the trees are regrown or replanted and the soil, water and biodiversity are protected."

But environmentalists say old trees are still being cut down when recycling alternatives exist. And it's not just about trees, they say. It's about carbon dioxide and ecosystems necessary to wildlife.

"The large old trees are the ones that do the most good," said Bill Grotts, program for the Heartland Tree Alliance, which is part of Bridging the Gap, a civic environmental partnership in Kansas City, Mo.

"They absorb the most water because they have more leaf area and provide the most cooling effect."

To him and others, that's the bottom line.