YAM CULTURE IX PORTO RICO. 21 
and more even-grained than the water yams and not less so than 
the roots of the White Guinea, Potato yam, or Congo varieties. It 
is rich yellow and of good texture when cooked. The flavor is pleas- 
ant and compares favorably in richness with the best yams. The 
vines of this variety are round, small, and very strong, and make a 
moderately vigorous growth. Unlike most varieties, this variety 
makes a slow growth throughout the year, and it is apparently un- 
affected by the long dry winter. The leaves and vines are pointed, 
tough, glossy, very dark green, and average about 5 inches in length 
and 3 inches in width. 
MAPUEY MORADO. 
The Mapuey moraclo is a variety well known throughout Porto 
Rico, where it is considered superior in flavor to any other yam. Its 
production per hill, however, is so low, unless the plant is grown 
under the most favorable conditions, that only a small area of land 
is devoted to it. It succeeds best on a very fertile, well-drained, and 
thoroughly prepared upland. In such places it yields sufficiently well 
to be profitable, because it always sells at a considerably higher price 
than other kinds. The club-shaped roots of this variety develop in 
hills near the surface of the soil much the same as sweet potatoes, 
groups of four to eight roots growing in a hill. The roots are 3 to 
8 inches long, 1J to 3 inches in their greatest diameter, and for more 
than half their length taper toward the slender rootstock. The 
skins are rough and corky over the rootstock and basal portion, but 
thin and tender over the remainder. The interior is solid, brittle, 
a rich purple in color, and contains 23.17 per cent starch in the fresh 
material. When cooked these roots are of first-class texture, and 
rich, pleasing flavor. The roots of this variety, being small, keep 
well. Since they develop near the surface of the ground they can be 
dug without injuring them. 
CONCLUSIONS. 
The yam. which is nonresistant to frost, thrives well in Porto Eico, 
where the climatic conditions favor its growth. It is one of the most 
important root crops of the island and one of the lowest-priced foods. 
It is grown in family gardens in all parts of Porto Rico because it is 
well adapted to many soil types. Practically the entire crop is grown 
for home consumption. 
Ridges of well-stirred soil and vegetable matter should be made 
sufficiently large when planting to enable the roots to make a normal 
growth above the water level in the soil and above the firm subsoil. 
The plants should be placed from 1 to 2 feet apart in these ridges, 
according to conditions peculiar to the root growth of each variety. 
