Environmental Engineering Reference
In-Depth Information
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Bush yam
Water yam
White yam
Yellow yam
Bitter yam
Bulbil yam
Chinese yam
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8
6
4
2
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Land-use systems
Figure 7.1 Diversity of yams in different land-use systems.
Indigenous cultural practices adopted for the different
types of yam
Bush yams (D. praehensilis) or wild rotundata
Ecology
Bush yams are grown in the home garden agroforestry systems, agroforestry non-
home gardens, orchards and plantations, and in annual cropping systems, but their
cultivation is mostly associated with orchards and plantations.
Time of planting
New bush yam plantings are normally made between December and February but
they may be planted in March. During the minor season, yam heads obtained
from tubers, which are milked for consumption in July, may also be replanted.
Such planting materials remain dormant in the planting holes until about
February when dormancy is broken. Subsequently they sprout at the same time as
the major-season plantings.
Land preparation
On fallows or new farmlands, the bushy undergrowths are slashed at the time of
planting.
