Assessment of indigenous tree species conservation in subsistence agricultural production systems: A case study of Lari Sub-county, Kiambu County, Kenya

Abstract

Abstract. Wawira KM, Thenya T. 2017. Assessment of indigenous tree species conservation in subsistence agricultural production systems: A case study of Lari Sub-county, Kiambu County, Kenya. Asian J For 1: 55-63. Conservation of indigenous trees is important because they regulate nutrients, build organic matter of topsoil, fix nitrogen and create habitat for beneficial soil micro-organisms. Subsistence agriculture is a typical land-use system in Kenya, especially in the humid and sub-humid regions. This research aimed to assess the types of indigenous trees, where they are grown, and why they are retained in agricultural production systems in Lari Sub-county, Kiambu County, Kenya. The results showed that various indigenous tree species were retained on-farm including Acacia abyssinica, Olea europaea, Ficus thonningii, Brachylaena hutchinsii, Allophylus abyssinicus, Vitex keniensis, and Prunus africana. The remnants of indigenous trees were scattered on farm with 57.4% along the boundary, 38.9% around the homestead, 2.6% inside the farm and 1.1% on riverine areas. Soil conservation, and timber and fuelwood provision were given as the main reasons for conserving indigenous tree species on the farm. While the main reason for planting exotic trees on-farm include economic purposes like income, fuelwood, and decreased land sizes, according to 60% of respondents. Overall, the findings indicate significant decrease in indigenous trees conservation on-farm due to longer maturity span compared to exotic trees. There is a need to promote alternative uses of indigenous trees as well as reinforce the 10% tree cover to include that 2% of the latter should be indigenous in nature.