Earth Notes - Wild Potatoes

Flagstaff, AZ – Earth Notes: Wild Potatoes

Like wheat and rice, potatoes are among the world's most important food crops. The tubers were domesticated millennia ago in Peru, where thousands of varieties occur.

But edible potatoes also grow in the Southwest. Archaeological evidence shows that potatoes have been used here for centuries. The Hopi and Navajo, for example, ate potatoes made in special clay dishes that neutralized the plants' bitter taste. Ancient members of the Zuni and Pueblo tribes also collected and cooked the vegetables.

A team led by geneticist James Bamberg found two species similar to common potatoes growing wild in Arizona and New Mexico. Archaeologists have found remains of such plants in area ruins. At some sites, potatoes still grow nearby.

It's presumed early farmers brought the first potato plants from Mexico, just as corn, tomatoes, and chiles moved north. Exactly when and how this happened is unclear. Also unknown is why plants at various locations are genetically different. But those differences may provide clues to how the crops were cultivated and distributed.

Wild crop populations aren't just a curiosity; they can help ensure the long-term health of domesticated food plants. Such plants continue to evolve defenses against pests, drought, and disease.

That genetic diversity provides insurance against events like the Irish potato famine of the 19th century, caused by a blight that affected a single type of plant. By studying and saving wild strains, we stand a better chance of having plenty of potatoes to eat for generations to come.

-Richard Mahler