Invasive Species Compendium

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Abstract

Bamiléké hedges and agriculture: an example from the Bafou district (W. Cameroon).

Abstract

A description is given of an area on the high plateaux of western Cameroon, which concentrates on the creation, utilization and use of hedges, a major feature of this wooded, bocage landscape. Hedges typically contain a mixture of tree and shrub species, have multipurpose functions, and are protected from browsing or trampling damage by horizontal bamboo fences. Hedge structure usually comprises: (1) timber or fruit trees >10 m in height (e.g. Cordia platythyrsa, Croton machrostachys, Dracaena arborea, Harungana madagascariensis, Markhamia lutea, Schefflera barteri, Ficus spp.) which are pruned or pollarded to reduce shading; (2) trees or shrubs 3 to 10 m in height, coppiced or cut to about 1.7 m height (e.g. Bridelia speciosa, Canthium spp., Datura stramonium, Hymenodyction floribundum [Hymenodictyon floribundum], Maesa lanceolata) the products are used for fuelwood or a source of cuttings; and (3) shrubs <3 m high, either planted (Dracaena deisteliana) or spontaneous (Allophylus hamatus, Clausena anisata, Erythrococca sp., Psorospermum spp.). The hedges may serve either as property boundaries, or as field boundaries - in the case of the former, the planting of fast-growing tree species is usually denser (about 0.8 to 1.5 m apart), and the hedge thus more impenetrable. Landscape modifications due to recent changes in agricultural practices in the area are briefly outlined. An important factor in these developments has been the introduction of a cash economy, principally coffee plantations, with Leucaena glauca [L. leucocephala] planted as a shade tree. This species has to some extent been replaced by others considered more useful, such as fruit- or oil-producing trees (avocado [Persea americana], mango [Mangifera indica], or butter tree [Dacryodes edulis]), or timber species. Various agroforestry systems have developed based on fruit production and timber/tree products. Commercial market gardening has been introduced, particularly in the N. of the area or in more pioneer agricultural areas - this system is incompatible with the traditional hedges containing mature trees, and monospecific hedges of Dracaena deisteliana, cut to about 1.6-m in height, are planted. Other economic factors noted are the decline in small-scale livestock (sheep/goats and pigs) raising, an increase in land pressure, and labour shortages. The hedge systems are considered to be good indicators of the dynamics of the agrarian economy.