Distribution, Utilization and Management of Prunus africana (Hook. f) in Gichugu Division, Kirinyaga District, Central Kenya

ABSTRACT

Prunus africana (Hook. f) Kalkman happens to be among the very important tree species. Its bark is used to treat prostate gland hypertrophy (PGH) and benign prostatic hyperplasia (BPH). The increased demand for its medicinal value, together with other uses, has led to the over exploitation of this species in its natural habitat. Its cultivation by small-scale farmers appears to be the only long-term solution for meeting future products needs and its conservation. There is however limited information on its current distribution, use and management on farmers‟ fields as not much research has been carried out. This study was conducted in Gichugu Division of Kirinyaga District in central Kenya to investigate the spread, utilization, management and constraints associated with Prunus africana, with a view to providing guidance for its introduction and domestication in agroforestry practices/systems. Three agro-ecological zones: lower highlands 1, upper midlands 1 and upper midlands 2, with 132 households as the units of investigation were randomly selected. In addition, a case study of 15 households was also randomly selected according to wealth status. Tree diameter at breast height or root color diameter (DBH/RCD) and total height of all trees of these households were measured. The results showed that, 53% of households sampled had Prunus africana, and its distribution was associated with agro-ecological zone (χ2 = 52.1, p = 0.001). There was a significant relationship between the number of Prunus africana trees and land size (r = 0.307, p = 0.01), land under trees (r = 0.361, p = 0.01), and significantly negatively correlated to land under tea (r= -0.312, p = 0.01). Prunus africana was also associated with the agroforestry practices/systems. It is concluded that; that spread of Prunus africana varied according to agro-ecological zone and its distribution was determined by age of household head, land size, land use, tree planting preferences and agroforestry practices. The number of Prunus africana on farms was influenced by socio-economic factors and most of the trees were found planted on the farm boundaries. Farmers used Prunus africana differently, and that the use for fuel wood (57.1%) and medicine (52.9%) are the most important uses. Pruning was found to be the most prevalent management technique and was mainly done to reduce shading of planted food crops. Farmers lacked knowledge in bark harvesting, which was being done unsustainably. Planting of Prunus africana was from wildings that had been natured during crop weeding, and grew from remnants left behind during land clearing for agriculture and settlement. Shading to crops (45.7%), lack of sufficient water for saplings (17.4%) and slow growth (13%) were rated as greatest constraints. On the basis of this study, it is recommended that increased cultivation and domestication of Prunus africana be promoted as this would benefit the welfare of local people, and improve the environment. Suitable niches for Prunus africana domestication exist on farm boundaries, steep slopes, soil conservation structures, and in home compounds. A policy should be enacted to streamline the harvesting and marketing of Prunus africana products to enable farmers‟ realize full benefits. Farmers should also be sensitized with information on best methods for regenerating Prunus africana, sustainable bark harvesting and marketing strategies. Further research is required on growth rates of different provenances and distribution of Prunus africana in the Mt. Kenya forest and also to determine the relation of the surrounding community with the forest resource.