Patti Wright, associate professor of anthropology at UMSL, studies the past interrelationships between people and plants or what is called “paleoethnobotany.” (Photo by August Jennewein)

For many families, a dish of candied yams is a staple on the Thanksgiving table.

But it turns out many people aren’t eating what they think they’re eating. Most candied yam dishes are in fact made with sweet potatoes. Many people have likely never eaten yams at all.

“A lot of people use the term sweet potato interchangeably when referring to yams, but they are not the same,” said Patti Wright, associate professor of anthropology at the University of Missouri–St. Louis, whose research focuses on past interrelationships between people and plants or what is called “paleoethnobotany.”

Wright doesn’t know how or when the mix-up began but said it’s pretty pervasive.

“I remember my mother and my aunt would make candied yams for Christmas,” she said. “They were actually candied sweet potatoes, but they called them yams.”

In fact, sweet potatoes and yams come from completely different plant families. They also differ in taste, starchiness and appearance. Sweet potatoes are short, blocky and smooth with thick skin, while yams are long, cylindrical with rough and scaly skin. Sweet potatoes taste sweet and yams taste starchy.

Poisonous past of the tomato

Tour a summer garden and inevitably there will be tomato plants. But the tomato wasn’t always a garden go-to. At one point in history it was shunned and considered poisonous.

Tomatoes are indigenous to Central and South America. After encountering them in those areas, the Spanish introduced the tomato to Europe. It became popular across Europe and in European colonies in the Caribbean, but not in England nor its colonies.

The tomato acquired its sinister reputation from John Gerard, an English barber who wrote a botany book in 1597, stating the tomato was poisonous. Its popularity finally took off in North America in the early 1700s when it was introduced into South Carolina from the Caribbean.

Today, the tomato is the No. 1 garden crop in the U.S. followed by zucchini. Tomatoes are also fruits, not vegetables as many people mistakenly believe. That’s because tomatoes have seeds.

Most of the world’s supply of tomatoes come from China, followed by India then the U.S.  And 90 percent of tomatoes in the U.S. come from California.