Not to beat a dead horse, just clarification for the interested:
According to _Funk & Wagnalls Cook's & Diner's Dictionary_, copyright 1968,
page 271---- Yam, noun, 1) The very large (sometimes weighing as much as 100
pounds), fleshy edible root of a climbing tropical plant (genus Dioscorea),
native to southeast Asia, Africa, etc. These, the true yams, are rarely if
at all seen in American markets. 2) In the U.S., a variety of the sweet
potato, snip3) In Scotland, the potato.
_The Healing Foods_ by Hausman & Hurley, copyright 1989, page 387--- Is it
a yam or a sweet potato? Here's the lowdown on how to distinguish the two.
A yam is a huge tuber that grows in very hot areas such as Central America
and parts of Africa. It does not grow in the continental United States, but
it is occcasionally imported and sold in big chunks in Latin markets and
Sweet potatoes are any of the almost 50 variety of tuber that find their way
to our holiday tables each year. snip
_Vegetarian Cooking for Everyone_, by Deborah Madison, copyright 1997, page
427---- Sweet Potatoes---We have long been in the habit of calling sweet
potatoes yams, although the true yam, a tropical vegetable, is seldom seen
outside of Latin markets. Regardless of what we call them, what we mean are
delectable sweet-fleshed tubers.
Types of sweet potatoes: Garnet or Jewel, Louisiana, and Jersey.
Mashed Sweet Potatoes, (adapted from Vegetarian Cooking for Everyone)
Leaving their skins on or not as you wish, mash 2 pounds baked, boiled, or
steamed sweet potatoes with 1 teaspoon grated orange or tangerine zest, and
the juice of an orange or tangerine.
Season well with salt and pepper and serve. Or try using any of these
traditional seasonings: bits of pineapple, candied ginger, bourbon, a few
pinches of nutmeg or cinnamon, allspice, and cloves. Serves 4 - 6