A grain of rice, like a grain of sand, sifts through your hands with a mysterious and lovely sameness. Mostly white or tan, hundreds or thousands of grains pour smoothly out of buckets, out of burlap, into bowls, with a sound like small waterfalls. Rice seems so simple, really. And yet, because it plays a central role in world cuisines, these modest grains can carry the weight of history. Sometimes that history is deeply surprising.

Trinidadian ethnobotanist Francis Morean is living that surprise. The 56-year-old grew up in Trinidad's Palo Seco hamlet, helping his mother and grandmother plant "hill rice" in the garden once the late-spring rainy season had begun. They would punch checkerboard-style holes in the ground with stakes fashioned from tree branches, and drop the rice seeds in. After harvesting, they would dry the rice plants on large cloths sewn together and laid in the sun. The dried rice plants were shredded by dancing and stomping on them barefoot, the hulls removed in homemade mortars and pestles. The rice stored well for years and was, says Morean, a cherished dish at the dinner table.

"In Sierra Leone and many West African nations, rice was an essential part of every meal," Morean says. "So being able to produce one's rice was a major plus for persons of the African diaspora."

And this particular rice, in the words of David Shields, author of Southern Provisions: The Creation and Revival of a Cuisine, was "the most historically significant African diaspora grain in the Western Hemisphere." Last month, Morean joined Shields and assorted rice geneticists, scholars, growers and chefs in Charleston, S.C., to attend a day-long tasting and presentation on the history of this unusual African rice that is, nowadays, causing a bit of a stir.

It's a rice that traveled from Africa to low country — the sea islands and coastal plains of the American Southeast – and was grown widely in Georgia, Alabama, Mississippi and Kentucky. While it was not a major commercial crop on plantations, for the enslaved Africans who worked them, it was a vital, edible link to the homes they and their ancestors had been wrenched from. It was then brought to Trinidad by formerly enslaved people called Merikins — a variant of "Americans" — where it thrived even as it vanished from U.S. fields. It is a seed that followed the slave trade, and its repatriation now may help fill in a critical missing link in Southern, African and Trinidadian foodways.

The rice belongs to the African genus called Oryza glaberrima, of which there may be 10,000 known varieties, according to molecular biologist Isaac Bimpong Kofi of AfricaRice Center. In contrast, there are more than 40,000 varieties of the Asian Oryza sativa, which most of the world knows and eats.

Originally called "red bearded upland rice" — and now dubbed Merikin Moruga Hill Rice — this strain gets its name from a reddish husk festooned with a "beard" of spiky plant hairs that protect it from pests and birds.

What makes this rice so special is how and where it grows. Rice loves water and thrives in coastal plains and marshes. But this strain can happily thrive upland, on higher, drier land — requiring, as the Pennsylvania Mercury put it in 1786, "no other watering but what they receive from the clouds."

Upland varieties of rice piqued the interest of many Americans in the late 1700s because it was thought they might compete with "swamp" rice and counter the mosquito-borne malaria infections that swelled in the coastal plains and swamps there every summer.

The red bearded variety came to America on a ship from West Africa. One of its biggest champions was President Thomas Jefferson, who sent the seeds to Charleston and Georgia. Shields unearthed a letter Jefferson wrote in 1808 in which he expressed hope that, if the upland rice "answered as well as the swamp Rice, it might rid them of that source of their summer disease."

In South Carolina, plantation owners who had already made fortunes growing Asian rice were indifferent to the new strain, according to Shields. But for enslaved Africans, it was a different story.

It "is probable that Africans recognized the seed, familiar from the markets of Guinea and Sierra Leone," Shields writes. On plantations of the Southeast, enslaved Africans grew the rice in their own backyard gardens, where they raised crops to supplement their often-meager provisions.

In exchange for their freedom, some enslaved Africans on the sea islands of Georgia volunteered to fight for the British and against their owners during the War of 1812. In 1816 the British settled these newly freed people in southern Trinidad, where they brought their favorite cultivars and called themselves Merikins.

In the Caribbean, the Merikins went on growing the rice, and it was adopted into the local cuisine. In the United States, however, the red bearded rice was displaced by more prolific Asian varieties and slowly went extinct — so thoroughly extinct that excavation and surveying over the last 40 years has not turned up a single seed or grain.

"An entire canon of lost Southern foodways vanished for 200 years," muses Glenn Roberts, founder of the heirloom grain purveyor Anson Mills, and president of the Carolina Gold Rice Foundation, which is aggressively pursuing research on upland strains of glaberrima. "And I don't understand why it vanished. The best of the glaberrimas practically grow themselves." He says they grow well upland, like wheat, they're slightly drought tolerant but also comfortable growing in flood culture. They even do well "floating where roots do not contact soil."

In 2015, Morean decided to take a trip to American libraries to research hill rice. "Articles in our archives on the island mention the connection of our rice to the Carolinas," he says.

But the libraries of Charleston, Atlanta and New Orleans, where he conducted research, contained no mention of the hill rice at all. "Nobody knew it was there," Morean says. "Nobody was writing about it, not even Judith Carney or Edda Fields-Black."

Carney is widely known for a luminous masterwork called Black Rice: The African Origins of Rice Cultivation in The Americas that explores the critical role Africans played in the rice production that led to such enormous wealth in antebellum South Carolina. Fields-Black, in turn, wrote Deep Roots: Rice Farmers in West Africa and the African Diaspora.

"I decided to hold a rice symposium on Trinidad, and invite everybody I could think of," says Morean, who was concerned that production was steadily declining on the islands. "I'd say there are only about 40 people still planting it, and most of them are over the age of 50. It's hard labor. The young people don't want to do it."

The symposium took place in December 2016 and drew, among many others, David Shields and members of the Gullah/Geechee community — the descendants of formerly enslaved Africans in rural low country, who keep many linguistic and cultural ties to Africa to this day. That included Marquetta L. Goodwine, who is chieftess of the Gullah/Geechee Nation (she's also known as Queen Quet) and renowned Gullah chef Benjamin "B.J." Dennis of Charleston.

"It was fascinating to see the rice cooked Merikin-style," says Chef Dennis, "in coconut milk, very starchy, almost murky. In contrast, Gullah cuisine prepares rice so that every grain is separate, like individual blossoms." Dennis says it's an easy-growing garden rice that he is certain will come back to the Gullah/Geechee community in the next few years. "Southern food in the U.S. is so similar to Afro-Trinidadian cuisine."

Roberts is determined to bring the rice back, and says that once it makes it through quarantine into the U.S., it will be genotyped to be certain that it is indeed the bearded upland rice of the late 1700s and 1800s.

The Carolina Gold Rice Foundation and Clemson University are now collaborating, spearheaded by Shields' research and documentation, as well as the skills of horticultural scientist Brian Ward of Clemson University Extension in Charleston.

Last year they obtained and test-planted 13 varieties of upland glaberrima obtained from the USDA's National Small Grains Collection in Aberdeen, Idaho. One of the upland bearded varieties is now growing in experimental plots in Texas, South Carolina and Martha's Vineyard in Massachusetts. "We intend to donate seed free of charge to communities across the South and Northeast," says Roberts of Anson Mills and the Carolina Gold Rice Foundation.

Interest in Orzya glaberrima is growing. In Africa, several organizations, including AfricaRice, are crossing upland varieties of African rice with Asian rice to produce hardier strains.

Roberts and Shields envision a time when red bearded rice and perhaps other upland strains can be grown by any gardener in their backyard, or even in a planter. That will be welcome news to Gullah/Geechee descendants and farmers, who might then grow their own ancestral rice once again.

Michael Twitty, a chef and culinary historian who explores African-American foodways and is the author of the forthcoming book The Cooking Gene, says there's always a risk that rediscovered cultivars will be subject to "cultural gentrification, where others repurpose the shell of our heritage. We have to know the value of our own African heritage. For us, these ingredients are part of a mosaic that comes with the blood."

Dennis agrees, and says, "It's up to us to tell our own story correctly. I feel our ancestors actually guide us and ask us to tell the story. And it makes my heart happy, chasing my ancestral roots through food."

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