After the winter that never seemed to end in our region, warm days signal spring’s arrival. Finally, barren stems and limbs show signs of green. But green also arrives as a state of mind. A story in the News-Press this week pointed to a trend toward reusable grocery bags, a movement of environmental concern. While hardly sweeping in itself, and probably not to everyone’s taste, this seems noteworthy as a changing American frame of mind, a recognition that small acts performed repeatedly might make some difference for our planet.

For anyone who has stood in a grocery checkout lane, the numbers hardly appear surprising. The Environmental Protection Agency estimates that the United States consumes 380 billion plastic bags a year. The EPA also estimated that less than 1 percent of the bags are recycled.

The plastic bags are, of course, used for a variety of things once they leave the retailers, everything from storage to trash can liners. Many end up in landfills, where the high-density polyethylene materials break down at a rate much slower than, say, a paper sack. Other of the bags find a place in what environmentalists refer to as “the litter stream.” A tree branch might break and fall in a high wind, but a plastic bag stuck in a tree branch tends to hang on forever.

While excessive consumerism might be seen only as an American affliction, the litter problem has a worldwide reach. In South Africa, the plastic bag has the mocking title of “national flower” because so many find a home along highways and in bushes.

Solutions arise. As our story pointed out, some people are now taking their own canvas bags to haul home their groceries. Supermarkets and retail stores in this area are supporting the practice, offering the reusable shopping bags for sale and providing a small refund to those who use them. (To be sure, the stores have a stake in this. By one estimate, the plastic-bag cost to retailers is $4 billion a year, and, as the point of origin, the stores suffer a greater litter problem than most locales.)

As solutions go, the canvas-bag movement shows environmental thinking at its best. One, it’s simple. Two, it comes not from governmental mandate but from concerned individuals and businesses; those cities enacting plastic-bag bans will have only added bureaucracy, enforcement issues and irked citizens to show for the effort.

The market decides. Given an idea, time and encouragement, people do the smart thing because it’s the smart thing.