Analysis of phenophases that control in-situ establishment of Ocotea usambarensis Engl. in the southern slopes of Mt. Kenya Forest

The existence of Ocotea usambarensis in Mt. Kenya Forest is threatened by extensive exploitation of both wood and
non-wood products and therefore requires urgent conservation measures to prevent further degradation. Assessing
phenological phases and their sequence determine the species establishment. This study therefore investigated the
phenology and establishment of O. usambarensis and its association with other plant species in Mt. Kenya Forest.
Three plots that were at least 5 km apart measuring 100 m x 100 m within the natural forest with mature O.
usambarensis species were purposely sampled on the southern slopes. Point centered quarter (PCQ) method was
applied in determining species association. Flowering, fruiting, leaf fall and leaf flush were determined as the main
aspects for phenological assessment. Data on environmental factors were monitored through the aid of automatic
weather station while phenophases were observed and recorded through classes of intensities. Shannon Wiener
diversity index was used to determine species diversity and importance while regression and correlation analysis
were used to determine the relationships among environmental factors. There was significant variation (P<0.05) in
flowering, litter fall and leaf flush. Mean flowering was 2.67 (42%) while no fruiting was observed during the study
period. Monthly variations in humidity, rainfall and radiation were significant (P< 0.05) while for temperature and
wind speed were insignificant. It was observed that Diospyros abyssinica was growing in close association with O.
usambarensis playing the role of nurse species. With the absence of seedlings in most of the sites and the limiting
environmental factors, promotion of vegetative propagation and enrichment planting would enhance conservation
and restoration of the species in Mt. Kenya forest