Regeneration Ecology of Erica arborea L.

Erica arborea is the dominant tree of the uppermost forest zone of the Simen Mountains National Park, Ethiopia. Only six other woody species are found between 3.100 m and 3.600 m elevation at the investigated sites. Many E. arborea stands of the Simen Mountains are considered endangered due to insufficient regeneration attributed to changes in land use. In this study the influence of disturbances on the stand structure, species composition, density of mature tree, saplings and seedlings, as well as on the soil seed bank were examined and the causes of seedling mortality, micro site condition, seed germination requirement and survival of E. arborea were investigated at three sites. The overall vertical distribution of the seeds in the soil was similar in all stands, with the highest densities occurring in the upper five centimetres of soil and gradually decreasing densities with increasing depth. For the successful germination of E. arborea and Hypericum revolutum charred soil showed great performance, compared to other seedbed conditions (exposed mineral soil, sand, forest floor and nursery soils). Fire has a profound positive effect on Erica regeneration.