Candied yams or Candied Sweet Potatoes? « Inside Adams

From the Library of Congress no less:
Candied yams or Candied Sweet Potatoes? « Inside Adams:

"What we call a yam in the United States (e.g., garnet yam or jewel yam) is in fact a softer variety of sweet potatoes. True yams, native to African and Asia, are drier and starchier than sweet potatoes.

To supplement this culinary history, I needed to understand the botanical relationships between the two. Botanically, a sweet potato and a yam are both flowering plants, but that is where the similarity ends. Yams are closely related to lilies and grasses, while sweet potatoes are part of the morning glory family."