Brittle corn stalks border a backyard garden in Flagstaff, Ariz., on a windswept mesa surrounded by ponderosa pine trees. They look dried-up and ordinary, but the garden's owner, Carol Fritzinger, says opening up the husks to see what's inside is like Christmas morning.

"Oooh, this one's a pink and purple variety," she says, laughing as she peels back a husk to show a translucent, rainbow-colored corn cob inside. "You just never know!"

"Glass Gem" is like no other corn in the world. It's a throwback to ancient varieties and bred specifically for its beauty. A photo of one stunning rainbow-colored corn cob went viral in 2012. Since then, it's inspired thousands of people to get involved with seed saving.

"I want everyone to grow it," Fritzinger says, showing off a cob patterned with red-and-white swirls like peppermint candy. "So I give as much seed away as people will take."

"Glass Gem" has its own Facebook page with more than 19,000 followers, but its journey from an Oklahoma cornfield to Internet fame started with a man named Carl Barnes. Barnes wanted to explore his Cherokee roots, so he began collecting and planting ancient varieties of corn. A mix of Cherokee, Osage, and Pawnee varieties produced two tiny, multicolored cobs, which he showcased at a native plant gathering. The colors enthralled a grower named Greg Schoen.

Barnes didn't have much of the unusual corn, but he gave a handful of kernels to Schoen. That was in the spring of 1995, around the time the Alfred P. Murrah Federal Building was bombed. Schoen, living in Oklahoma at the time, was carrying the kernels around in his pocket when the news of the bombing reached him. He pulled them out and looked at them.

"It was like I got this strong impression," he remembers, "a voice was saying: this seed is going to change things."

Schoen moved to New Mexico a few years later, planted the corn, and crossed it with Pueblo popcorn. Ears appeared with not only brilliant colors but a shiny, glasslike hue. Schoen felt it was more than a pretty plant. It was a piece of the past that had nearly been lost. He says corn is woven with human culture, but diverse traits bred by generations of farmers began to vanish when agriculture became big business. For Schoen, saving that heritage wasn't just about genetic variety: "it also has cultural memory, and that's a powerful force."

Schoen gave away seeds to anyone who wanted them, including Belle Starr and Bill McDorman, a couple who had just started a seed saving school in, of all places, Cornville, Arizona. Starr and McDorman didn't know what to expect from their first crop of corn. But they took a group of students out to the garden to shuck off the husks at harvest time.

The colorful cobs that emerged were "beyond belief," McDorman says. Starr adds, "People were crying in our class, they were literally crying, it was so beautiful."

A year later, McDorman and Starr took over directorship of the nonprofit Native Seeds/SEARCH in Tucson. They put a photo of the multicolored corn on the Website with Greg Schoen's original caption: "Glass Gem." Thousands of orders for seeds poured in. Other seed-saving groups took up the challenge of increasing the small stock of Glass Gem. So many people tried to order it from a company called Seeds Trust, their Website crashed.

"One ear of corn is that famous picture of Glass Gem," McDorman says. "One little ear that's now changing the world... and has, in the end, been called the poster child for the whole return to heirloom seeds."

Starr and McDorman are now the directors of the Rocky Mountain Seed Alliance, a group that saves seeds by giving them away through a network of "seed stewards." Its mission is to protect locally adapted seeds that produce hardier, tastier — and prettier — crops, part of a larger vision for a more sustainable food system. "When you start saving seeds from something you've grown," McDorman says, "and then plant it again, you're rejoining a ritual — a 10,000-year-old ritual — that created all the foods we eat out of wild plants." For him, the story of Glass Gem corn isn't just about food or beauty. It's about protecting stories and a sense of place.

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