On a drizzly spring morning in a small town in rural Ontario, an event hall fills up with farmers who dominate production of one of the world's most valuable crops: ginseng.
In a sea of baseball caps, camouflage-print jackets and jeans, more than 100 growers have come for their annual association meeting. The gathering in Delhi, a town of 4,000, is the biggest turnout in a long time, because, after years of stellar growth, a mystery has enveloped the industry-their biggest customer has disappeared.
Farmers talk in low voices at the back of the room about what has happened to Hang Fat, the company in Hong Kong that had become the biggest buyer of the crop over the past few years before suddenly stopping payments.
"There's tension and there's scepticism, and there's obviously some worry in the farming community," said Larry Sitko, who's been growing ginseng since starting with one acre in 1991.
"The ginseng industry isn't going anywhere, but it might hurt a number of growers who haven't had their money."
How did a rural county in Canada became the centre of a trade worth half a billion dollars a year, linking the fate of hundreds of family farms to a gnarled root prized in China as a medicine and health food?
It begins more than three centuries ago, with Canada's first inhabitants, an 18th-century Jesuit priest and some of the earliest trade between Canada and China.
The aboriginal Iroquois people of eastern Canada were the first known users of ginseng in North America, harvesting the wild root for use in ceremonies and as medicine to relieve fever, ease sinus problems and reduce swelling. In the United States, the Cherokee thought ginseng could "make itself invisible to those unworthy to gather it."
It was invisible to everyone else until Jesuit priest Joseph-Francois Lafitau started hunting for the root around 1715. Aware of its value to the Chinese, he flagged its presence to traders who soon made it one of Canada's earliest and largest exports to Asia. It didn't last long. By the 1750s, trade collapsed due to overharvesting and the traders' failure to dry the root properly, yielding a lower-quality product.
By the late 1800s, ginseng was being cultivated in Ontario in small quantities, but Ontario farmers were much more interested in another crop that was rising in demand the world over: tobacco. It wasn't until the 1980s, when government restrictions on tobacco companies and more health-conscious consumers reduced demand, that growers began looking for an alternative that would thrive here and provide the same high returns.
From then on, ginseng boomed. Ontario farmers are set to grow a record 8,277 acres (3,350 hectares) of ginseng this year, according to the industry association, almost double the land devoted to the root in 2001. The root contributes more than C$600 million ($472 million) annually to the economy, the industry association said at its meeting.
On the back roads off Highway 403 leading to Delhi, two hours from Toronto, you pass between rows of hay-covered mounds that contain the growing yellow root. Between them are meter-high poles holding rolled up black tarp that will be spread to provide shade in the summer, when the mounds erupt with green foliage and red berries.
It's the region's lifeblood and the farmers here are cautious about revealing too much that could give clues as to last year's crop or their finances. At the annual meeting, few attendees ask questions openly. Instead they huddle in groups during the break, hoping to gain a better understanding of what has happened to the buyer from Hong Kong, what will happen to prices, who will buy their crop.
"There's a lot of confusion," said Henry Kukielka from his tractor on his farm in the nearby town of Vanessa. He's been farming for more than three decades and grows ginseng, vegetables, and corn. "You have to weather the storm. We're survivors here."