CULTIVATION OF THE TRUE YAMS. 15 
which the name yam has been erroneously applied. The plants of 
the yams are climbing, twining vines. Nearly all of them bear their 
main crop of tubers in the ground, but some produce aerial tubers 
in the axils of the leaves, and a few bear aerial tubers almost ex- 
clusively. 
Yams are much like the potato in composition and food value, and 
many of them when prepared for the table are equal or superior to 
it in appearance and taste. They are baked, boiled, fried, and 
cooked in the various other ways in which potatoes are used. Yams 
mature in the late fall or early winter and should be grown widely 
for home use and local markets in the South Atlantic and Gulf 
regions to supplement the fall potato crop. 
Of the several important edible species the greater yam (Dios- 
corea alata L.) is one of the most valuable and most widely dis- 
tributed, and several varieties of it are now cultivated for home use 
or for market by a considerable number of people in Florida and 
near-by States. A market for home-grown yams has existed in New 
York among the West Indian population since 1918, when, in order 
to avord the danger of introducing certain injurious insects, the fur- 
ther commercial importation of yams from the West Indies and else- 
where was prohibited. 
A season of at least 8 to 10 mdnths is required for the successful 
cultivation of yams as a crop, but the vines are ornamental and may 
be grown for porch decoration and similar uses even where the season 
is materially shorter. 
The labor involved in properly preparing the land for planting 
yams and for the proper handling of the crop when grown makes 
the cost of production higher than that for other tuber crops, but on 
the other hand this vegetable commands a considerably higher price 
on the market. The great excellence of the best yams as food gives 
reason to believe that the crop will become the basis of an agricul- 
tural industry of importance in the South. 
