Confusing Tubers in the New World

I've been on a personal campaign over the past few years to better educate Americans about tubers. Not all tubers, mind you, but two in particular: the sweet potato and the yam.

Go into almost any American grocery store or produce stand and you will find a sign, next to a colorful vegetable that looks like an elongated potato, that announces that this item is a yam. Be forewarned, it is not. It's really a sweet potato!

But, I hear you protest, there is another sign next to a similar vegetable that indicates this one is a sweet potato. The truth is both of the vegetables labeled "sweet potato" and "yam" are sweet potatoes.

According to the Wikipedia, a yam

is the common name for some species in the genus Dioscorea (family Dioscoreaceae). They are cultivated for the consumption of their starchy tubers in Africa, Asia, Latin America and Oceania. They are used in a similar fashion to potatoes and sweet potatoes. There are hundreds of cultivars among the cultivated species.

Yams can be quite huge, some weighing at least 100 lbs. The skin of this vegetable is tough and gnarly. And you've got to cook it before you eat it, lest you make yourself sick.

Contrast this to the sweet potato:

The sweet potato (Ipomoea batatas) is a crop plant whose large, starchy, sweet tasting tuberous roots are an important root vegetable. The young leaves and shoots are sometimes eaten as greens. The sweet potato is only distantly related to the potato (Solanum tuberosum). Although sweet potatoes are sometimes called "yams" in the United States, they are even more distantly related to the true yam (Dioscorea species).

As you can easily see, the sweet potato and yam don't even originate from the same plant family. While the yam sports a tough exterior, the sweet potato's skin is thin and can be easily removed. Sweet Potatoes can be eaten raw and they won't make you sick.

So please help me out. Next time you visit your local market, help spread the word that yams and sweet potatoes are not one in the same. In fact, few American stores carry yams at all.

If we can better educate American companies, produce managers and consumers about this important difference, then maybe we can tackle our next project -- world peace.