Baku  (Tieghemella heckelii)

Classified as Endangered (EN) on the IUCN Red List 2007 (1).

This beautiful, tall forest tree is also a commercially valuable timber species (3). The trunk of the baku is straight, cylindrical and covered in thick, grey bark with smooth ridges (3) (4). The simple leaves, around 15 centimetres long, are arranged alternately along the stem (3), and are often dry and dark (4). Baku trees bear white flowers and fruit that measures about ten centimetres long and eight centimetres wide. One to three large, oily seeds are imbedded within the yellow pulp of the fruit (3). The inner part of the trunk, or heartwood, ranges in colour from pinkish-red to a darker brownish-red (2), while the outer part, the sapwood, is lighter in colour (3).

Occurs in West Africa, where it has been recorded from Cameroon, Côte d’Ivoire, Gabon, Ghana, Liberia, Nigeria and Sierra Leone (2).

The baku grows in evergreen, moist, semi-deciduous forest (4)

The fruit of the baku are a favourite food for both small animals, particularly rodents, and forest elephants (Loxodonta cyclotis) (5) (6). This results in the large, oil-rich seeds being carried away from the parent tree to a new location where the seeds can germinate and grow. Forest elephants were believed to be the principal or sole animal to disperse the seeds (7), but the baku has been found to also reproduce in areas where forest elephants are not present (5). Baku seedlings are tolerant of shady areas, and grow rapidly when exposed to light, but are rare due to the high levels of predation by rodents, which feed on the large, oily seeds after germination (8). Locally, the oil from the baku’s seeds is eaten by people and the fruit is used to make soap (2).

The beautiful baku is threatened by over-exploitation for its attractive wood (8), which is used as timber and in the production of musical instruments (2). The forests of West Africa have been reduced to fragments due to harvesting, and primary rainforests in Côte d’Ivoire, Guinea, Nigeria and Sierra Leone now cover less than ten percent of their original extent (2). Ghana and Liberia both have a higher percentage of their natural forests remaining, but even in these countries, populations of baku have experienced significant declines and the extinction of this important species is a possibility (2). Illegal and poorly controlled logging pose the greatest threat to the baku’s continued existence (2), but it has also been reported that the reduction of forest elephant numbers in certain areas may limit the natural regeneration of baku (2) (8).

Baku trees are protected by law in Côte d'Ivoire, and due to the problem of overexploitation of timbers, Ghana and Liberia have imposed bans on the exporting of baku in log form (8) (9). Despite these measures, improved regulation of the timber trade is still urgently required (2). It has been recommended that re-planting in Liberia is necessary to prevent this species’ extinction (8), and in all areas in which it is harvested, certified sustainable forest management to Forest Stewardship Council (FSC) standards are required (2). The Global Trees Campaign was set up with the aim of saving the world’s most threatened tree species, of which baku is one of, and as a result, Flora and Fauna International is currently working in Liberia, with local and international partners, to improve the basis for the conservation and sustainable management of forests (2). Hopefully, through the provision of information, and the encouragement and support of sustainable-use operations (2), valuable and beautiful trees such as the baku can be conserved.

To support the Global Trees Campaign see:

Global Trees Campaign:
www.globaltrees.org

For information on Forest Stewardship Council standards see:

Forest Stewardship Council:
www.fsc.org