Diversity and ethnobotany of ferns in Mabira Central Forest Reserve, Uganda

Abstract

Ferns are the most diverse seedless vascular plants with a cosmopolitan distribution. In Uganda, 259 species are known. Their composition in many forests and use values to the surrounding communities remain understudied. This study explored the diversity of ferns in Mabira Central Forest Reserve, the association between epiphytic ferns and their host trees, and their utilization in adjacent communities. Diversity of ferns and their association with host trees were studied in 10m × 30m plots established along 1km long transects in each forest management zone. The number of transects varied with size of the zone. Utilization of ferns was studied in seven enclaves within Mabira CFR. Data were collected from 73 respondents identified by snowball sampling and interviewed using a semi structured questionnaire. Forty-five species of ferns belonging to 22 genera and 11 families were recorded, with Asplenium angolense being a new record for Uganda. Pteridaceae (5 genera, 13 species) and Aspleniaceae (1 genus, 11 species) were the most diverse families and the most speciose genera were Pteris (11 species) and Asplenium (7 species). A moderate association between epiphytic ferns and their host tree species was recorded (χ^2 (165) = 286.7, p<0.05: Cramer’s V = 0.504). Ferns were mostly utilized as medicines and in traditional divinities. Platycerium elephantotis (RFC = 0.71) and Thelypteris dentata and T. parasitica (RFC = 0.53) were the most useful ferns. Use of herbicides (36.5%) and forest destruction (30.6%) were the major threats to ferns. The study concluded that Mabira CFR had a moderately high diversity of ferns but their utilization in the surrounding communities was low. None of the epiphytic ferns was host specific. Strict protection of the forest should be intensified to conserve the ferns. Further surveys on ferns and their use within other forests is recommended to enrich the known pteridoflora of Uganda and reveal more traditional knowledge on their use.