Thirty years ago, long before LEED, Energy Star, or any other official green building guidelines existed, Stanley Selengut leased 14 acres of land along the two smile-shaped coves of Maho Bay on the U.S. Virgin Island of St. John. Over the next few years, he built 114 one-room wood-and-vinyl tents behind the turpentine and kapok trees, perched along wooden walkways that hovered over the soil so visitors wouldn’t damage the ground cover as they walked down to the beach or up to the restaurant pavilion, which was tucked back on a cliff overlooking the ocean. Water and electricity lines were laid beneath the walkways, precluding the need for trenches. “When I finished building the place, it looked like it had grown there,” Selengut says. The Maho Bay Campground is one of the country’s oldest—and perhaps crudest—eco-resorts.

Selengut, who turned 78 in April, is an accidental ambassador of eco-tourism—the word wasn’t even in vogue back at Maho’s beginning—and indeed had no intention of becoming a green developer, or wielding environmentalism as a marketing tool. He started as a U.S. importer of Latin American crafts in the 1950s, helped set up craft cooperatives, and consulted for the Kennedy administration. In 1976, he was working as a housing consultant for the Rockefellers, who introduced him to the Virgin Islands when the land along Maho Bay was up for rent. “I never dreamed of turning it into a big business,” he says. “When I got there and looked at the land and fell in love, I took a long lease.”

Five years later, he started buying land along the southeastern side of the island for what eventually would become Maho’s spiffier, greener sister resort, Concordia. The resorts became popular destinations for environmentally conscious travelers, and today, business is booming. Concordia’s restaurant opened this spring, and eventually a performing arts center, yoga pavilion, crafts center, and residential component—along with what Selengut says will be affordable housing for both residents and guests—will follow. But as Concordia expands and its future brightens, Maho’s star may be dimming. Selengut owns Concordia’s land, but Maho’s lease will finally be up in 2012, and it looks like the owners won’t let Selengut extend it. It’s a bittersweet time for Selengut as he, and Maho’s many faithful visitors, face what could be the end of an era.

I imagined that St. John would be overly touristy, but when I showed up in late January—in the lull between Christmas and spring break—I was surprised at how exotic and peaceful it seemed, and by how much its 28 square miles of terrain varied. The west and north sides are lush and busy with tourists, but the east side is nearly empty, with vast fields of fuzzy, red nipple cacti on promontories stretching out to the sea. Dramatic volcanic mountains are everywhere you look. Two thirds of the island is designated as a national park, and there are only two traditional resorts there—the Rockefeller’s Caneel Bay and the Westin. Of course, that’s likely to change when Maho’s lease expires. You can feel the tension in the air, the pressure to seize what little land is both undeveloped and free from park protection—which is precisely what makes Maho so precious.