Called "Turn Over A New Leaf," kicking off April 20 and running through April 27, the campaign is "designed to support, educate and inspire sustainability and eco-friendly practices in everyday life," says the retailer.

While it gets harder and harder for such marketing efforts to break through the clutter of green claims, experts say that Macy's effort may go over well with consumers for two reasons. The first is its link with an independent organization, especially one as well-known as the National Parks Foundation.

"We are really at the point of eco-saturation," says Raphael Bemporad, a principal at BBMG, a branding agency in New York. "Green buzzwords have become ubiquitous, and they just don't mean anything. And that's created a backlash of skepticism among consumers." So while many consumers will no doubt think Macy's (along with many other companies) is just blowing green smoke, the link to a reputable nonprofit carries considerably more heft.

And second, relatively few department stores have staked much of a claim in the environmentally correct space, "leaving lots of room for companies that want to be pioneers there," he says.

For retailers, most environmental claims have focused on food--including the debate over organics or the use of energy, whether that's Wal-Mart pushing CFL light bulbs or Safeway touting its solar initiatives.

But apparel is something of a void, primarily due to the fact that so little clothing can make genuine eco-friendly claims--only a fraction of the world's fabrics are grown organically, and much of the clothing Americans wear is stitched in places with less-than-progressive labor and trade policies, and consumers don't complain much about it.

But that may be changing. "People's ideas of corporate responsibility are moving beyond what's green and what's sustainable," he says. "It's starting to include a greater sense of social impact and fair trade. It's evolving into something more holistic than just plain green."

BBMG, for example, found in a survey it conducted late last year that nine out of 10 people think of themselves as "conscious consumers." About 90% say they are more likely to buy from companies that promote efficient energy practices, and 87% say they are more likely to buy from companies committed to environmentally sound practices, all things being equal. But only 65% of respondents say that the term "green" describes them well.

During Earth Week, Macy's says it will highlight eco-friendly clothes and products from leading vendors like Origins, Hush Puppies, DKNY and Macy's brands, including Style & Co. Sport and Haven by Hotel Collection.

The chain says it will donate all ticket proceeds from One Good Turn, on its national charity days, to the NPF. (Customers purchase $5 tickets to One Good Turn, which provides them with 20% off most apparel, and 10% off select home furnishings.) The two-day pass is good for both April 26 and 27.

That makes the NPF the "first charity in Macy's history to be the sole beneficiary of a national charity-shopping event," says a spokesperson. Typically, Macy's uses charity-shopping days to benefit local groups, in conjunction with new store openings. Its national event, usually held in the fall, has benefited many local and national charities, including the American Heart Association's Go Red for Women effort. Last fall, Macy's raised $9.5 million.

The promotion also includes the sale of a natural cotton reusable tote bag for $3.95, with $1 from each purchase going to the NPF. For the celebration of the actual Earth Day (Sunday, April 22) the company is handing out saplings to the first 100 shoppers at each store.

Macy's will support the effort with print, radio, and TV advertising, highlighting the One Good Turn event.

Online, the company is promoting two sweepstakes to support the effort, with prizes including a hybrid SUV as well as trips to the Florida Everglades and other national parks.

Of course, whether Macy's promotion will actually convince shoppers its heart is in the right place is hard to say. Certainly, consumers are much harder to convince than they have been in the past. "Marketing is only one part of what a company does, and if shoppers don't believe that doing the right thing is truly in a company's DNA, they won't buy it. They want to see evidence of a deeper commitment."

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