Simon Kosgei Choge 153THE RESOURCE BASEBrachylaena huillensis
Arabuko Sokoke Forest Reserve is the main source of Brachylaena huillensis to
woodcarvers within the study area and beyond. It is the last remaining tract
of lowland forests in Kenya (MENR 1994). Within Arabuko Sokoke Forest Reserve,
Brachylaena huillensis occurs on deep and well developed red volcanic clay
loam soils and is closely associated with Cynometra vegetation types, of which
two discrete populations in the forest are found. From the forest formations
where Brachylaena huillensis are found, wood volumes are estimated at 2.7
m^3 /ha in trees of size above 30 cm diameter at breast height, 50% of which is
assumed to be suitable for carving (KIFCON 1991). In addition, the recruitment
potential in these areas was also found to be healthy with over 2,500 seedlings
per hectare (KIFCON 1991). However, a rapid decline in numbers of mature
Brachylaena huillensis trees through overexploitation for carving is the most
serious conservation threat. Although the recommended sustainable annual
extractable volume of the species from the forest was estimated at 47 m^3 in
the late 1980s and early 1990s, licensed extraction of over 400 m^3 and illegal
harvests of over 2,100 m^3 were observed, at which rate the species could be
exterminated from the forest in about 17 to 25 years (KIFCON 1991). Better
enforcement of policing and protection of the forest in the late 1990s led to
controlled harvesting. For example in 1998 to 2000, about 340 m^3 Brachylaena
huillensis round wood was extracted annually from the forest (Choge 2002).
Brachylaena huillensis is a dioecious tree pollinated by insects. The flowering
period tends to follow the rainy seasons and rainfall quantity determines whether
the tree will flower or abort the young developed flower buds (Albrecht 1993).
Seed viability is extremely low (2%–10%) and is completely lost after six months
of storage at room temperature (Kigomo 1989; Albrecht 1993). In naturalPhoto 1. The raw material (Photo by S.K. Choge)09woodcarving.p65 153 22/12/2004, 11:05