Blogger's Note: With the holidays right around the corner, let's investigate one of the South's favorite tubers, the sweet potato and what sets it apart from the traditional yam. (Above): A true yam (left) compared to an orange-fleshed sweet potato (right).is the difference between sweet potatoes and yams? Althoughyams and sweet potatoes are both angiosperms, flowering plants,they are not related botanically. Yams are a monocot, a plant havingone embryonic seed leaf, and from the Dioscoreaceae or Yam family. Sweet Potatoes, often called ‘yams’, are a dicot, aplant having two embryonic seed leaves, and are from the Convolvulaceaor morning glory family. (Above): An example of African yams. Yams are closely related to lilies and grasses. Native to Africaand Asia, yams vary in size from that of a small potato to arecord 130 pounds (as of 1999). There are over 600 varietiesof yams and 95% of these crops are grown in Africa. Comparedto sweet potatoes, yams are starchier and drier. (Above): These are Louisiana Sweet Potatoes. The many varieties of sweet potatoes, Ipomoea batatas, are membersof the morning glory family, Convolvulacea. The skin color canrange from white to yellow, red, purple or brown. The flesh alsoranges in color from white to yellow, orange, or orange-red. Sweet potato varieties are classified as either ‘firm’ or ‘soft’. When cooked, those in the ‘firm’ category remainfirm, while ‘soft’ varieties become soft and moist. It is the ‘soft’ varieties that are often labeledas yams in the United States. Why the confusion? In the United States, firm varieties of sweet potatoes were producedbefore soft varieties. When soft varieties were first grown commercially,there was a need to differentiate between the two. African slaveshad already been calling the ‘soft’ sweet potatoes ‘yams’ becausethey resembled the yams in Africa. Thus, ‘soft’ sweetpotatoes were referred to as ‘yams’ to distinguishthem from the ‘firm’ varieties. Today the U.S. Department of Agriculture requires labels withthe term ‘yam’ to be accompanied by the term ‘sweetpotato.’ Unless you specifically search for yams, which areusually found in an international market, you are probably eating