Baobab Monograph.pdf - Crops for the Future

3.2 Regional diversity and distribution
As would be expected with such a wide distribution, botanists have recorded
certain plant characteristics that appear to represent morphological types. For
instance, Oliver (1868) noted that Mozambiquan trees had narrower leaves
than other types and Worsfold (1899) and Chevalier (1906) noted diverse
fruit types in West Africa and North Mozambique, respectively. Much more
scientifically-based work is needed to consider patterns of genetic diversity
in relation to distribution.
It appears that the extant distribution is probably determined by minimum
requirement for a certain annual precipitation - hence its occurrence, at
times, in upland areas coupled with the need for a dry season. Its relatively
wide ecological tolerance (see Chapter 7), and its amenity to artificial
propagation (see Chapter 8) suggests that some wider provenance testing
should repay dividends. Trials initiated in the 1970s used exceedingly
narrow variation.
3.2.1 West and Central Africa
Baobab is typically a scattered tree in the savannah, and also along tracks
and associated with habitation. Its frequent association with similar habitats
of Tamarindus indica (tamarind) (plates 28 and 29), Butyrospermum
paradoxum (shea), Parkia spp. (locust bean), Balanites aegyptiaca (desert
date) or Acacia albida (Wickens, 1982) places it into a category of incipient
domesticate and a likely tolerance beyond its natural home into ecotones.
It is also found on coastal areas e.g. estuarine areas of Senegal, coastal plains
of Ghana, Benin and Togo, also coastal regions of Zaire, suggesting
secondary colonisation after introduction.
3.2.2 Northeastern Africa
A northern limit is in semi-desert scrub and it becomes more common as
annual rainfall increases. In Eritrea and Somalia it is typically lowland, but
in Sudan it thrives in the Nuba mountains.
3.2.3 Eastern Africa
In Kenya, southwards to Mozambique, populations are coastal as well as
scattered in lowland bush and scrub, although in Tanzania it is a relict on
upland plateaux cleared for cultivation.
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