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THE CHINESE YAM. 
Its cultivation is easy, and it is very prolific, yielding 
not only underground tubers, but also small serial tubers 
in the axils of the leaf-stalks, which serve as sets for 
planting, to produce a crop of tubers, suitable for sets for 
the succeeding year’s crop. 
It thrives best in loamy or sandy soil of a deep and rich 
nature, but it succeeds well in any good soil, which, if 
deeply trenched and well manured, produces tubers of an 
astonishing size. 
The roots, or tubers, are fusiform, and in shape some- 
thing like a carrot or parsnip, but with this difference, that 
the large end grows downwards ; and they are of great 
length, being usually from eighteen inches to two feet long, 
and tapering from two inches in diameter to about half an 
inch, in tubers of the size which are most convenient for 
use. It is a peculiarity of the plant, however, that the 
produce is in proportion to the size of the set planted, and 
by using large sets, tubers of over a hundred pounds can, 
imder favourable circumstances of soil and climate, be pro- 
duced. The Chinese yam is a climber, and it does best when 
there is something for the runners to twine round, such as 
a few rods or a wire stretched along the row ; the reason 
being that the young shoots are very brittle and tender, 
and they are liable to be damaged by the wind blowing 
them about, and injuring the top buds of the runners. 
The best sets to plant are the small ends of the tubers, 
about six to nine inches long, with the small end uppermost, 
the bud coming from that part first, and most readily. As 
this portion of the tuber is too small for the table, it is 
usually saved for planting. Any fragment of the tuber 
will, however, form a plant, as there are dormant eyes all 
over its surface, from which buds will proceed. ^Vhen the 
ground is cleaned, manured, and prepared, the sets should 
be planted in ridges eighteen inches apart, in a sloping posi- 
