Population structure and phenological patterns of milicia excelsa in moist evergreen afromontane forests of Southwestern Ethiopia

Abstract

Knowledge of population structure and phenological patterns is basic to understanding the biological process, impact of disturbance, and forest successional trend. The main objective of this paper is to investigate the population structure and phenology of Milicia excelsa for seed production area. This study was conducted in Yayu and Bebeka natural forests, South West Ethiopia. Systematic sampling method was used to collect the data. Ten line transects were laid down along the gradient at each 100 m interval. Sample plots of 20 × 20 m for trees and saplings and 5 × 5 m for seedlings were laid down along transects at 50 m interval. Within the main plots, sub-plots for seedlings were laid out at the four corners and centre. A total of 60 quadrats were sampled at the Kebereta (Bebeka) and Dawe (Yayu) sites. DBH and height of trees were measured from each main plot. Data on phenology study was collected from both primary and secondary sources. The results of the distribution of the population of M. excelsa exhibited almost irregular pattern across the selected natural forests. The regeneration status of M. excelsa is ‘fair’ at the Bebeka site and ‘none’ at the Yayu site. M. excelsa has the highest proportion of individuals in natural forest at the Kebereta site than at the Dawe site; thus, it is more favourable to establish a seed production area there.