Hu Aishan, also known as Yam, is the name of the finished product of Yam. It is the root tuber of Dioscorea zingiberensis, a perennial herb of Dioscoreaceae, which is excavated in winter. It grows at an altitude of 350 meters to 1 100 meters, mostly on hillsides, under valleys, roadside bushes, streams and weeds.

Cassava, erect shrub, cylindrical root. Leaves papery, nearly round in outline, palmately parted almost to the base, oblanceolate to narrowly elliptic, tapering at the top; Stipules triangular-lanceolate, entire or with 1 to 2 bristles. Panicle terminal or axillary, bracts strip-lanceolate; Calyx purple-red, with white cream; The seed is about 1 cm long, slightly trigonous, with hard shell, stripes and smoothness.

So yam is different from cassava.