Common Name: Yams
Description
Yam is the common name for some plant species in the genus Dioscorea (family Dioscoreaceae) that form edible tubers.
These are perennial herbaceous vines cultivated for the consumption of their starchy tubers in Africa, Asia, Latin America, the Caribbean and Oceania. There are many cultivars of yam. Although some varieties of sweet potato (Ipomoea batatas) are also called yam in parts of the United States and Canada, sweet potato is not part of the family Dioscoreaceae but belongs in the unrelated morning glory family Convolvulaceae. . . . .Read more

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Common Name: African Medlars
Description
Vangueria infausta is a deciduous tree 3-8 m in height with a short trunk and hanging branchlets. Bark pale grey-brown, peeling in untidy flakes; branches usually opposite with reddish tomentose young branchlets.
Leaves dull green, opposite, rusty tomentose, medium to large, 5-24 x 3.8-15 cm, shape varying from ovate or obovate to lanceolate or rounded; net-veining, conspicuous below. Leaf apices either obtuse or sub-acuminate; base tapering; margin entire; petiole 3-10 mm long. Leaf stalks short, 5-10 mm long; stipules long, between young leaves. . . . .Read more 
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Common Name: Sour plum
Description
Ximenia caffra is a sparsely branched shrub or small tree to 6 m tall with a shapeless, untidy crown. Branches and twigs are armed with stout axillary spines and are glabrous or dense tomentose. Bark is grayish-brown to black, longitudinally fissured bark, red slash and rough on older, larger species.
Leaves simple, alternate, elliptic to lanceolate, 2.5-9 cm long by 1.2-5 cm wide, leathery, blue-green, often fascicled on dwarf, lateral shoots, margin entire, apex rounded or notched, base broadly tapering to rounded, often hairy when young and turning to shiny green when getting older and petiole about 8 mm long. . . . .Read more
References
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