This study investigates the impact of selected agroforestry tree species on soil carbon content and pH levels in the Eastern Highlands of Kenya. The increasing demand for sustainable agricultural practices necessitates an understanding of how tree integration affects soil health. Field experiments were conducted on farms with varying densities of common agroforestry species, including Grevillea robusta, Ficus sycomorus, and Morus alba. Soil samples were collected from different depths and analyzed for total carbon content and pH. The results indicated a significant increase in soil carbon levels in plots with tree species compared to control plots without trees. Additionally, notable changes in soil pH were observed, with some species leading to acidification while others enhanced alkalinity. These findings highlight the crucial role of agroforestry in improving soil quality and suggest that the strategic selection of tree species can optimize soil carbon storage and pH levels, contributing to sustainable land management practices in the region.

Soil Carbon, Soil pH, Agroforestry

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