Releasing Rain Forest Succession: A Case Study in the Dicranopteris linearis Fernlands of Sri Lanka

background

This study evaluates the effectiveness of different site treatments for controlling the invasive fern Dicranopteris linearis which has arrested forest succession in areas of the Sinharaja Man and Biosphere (MAB) reserve in lowland Sri Lanka. The fernlands, which had existed in the reserve for 10-20 years before this study, are favored by forest clearance for swidden agriculture and periodic fires. 

Research Goals & Methods

Different treatments were tested (weeding with machetes, root removal, till-clean weeding with root removal, and no treament as a control) and plots were censored 9 times within 55 weeks.

Conclusions & Takeaways

The till and root removal treatments were more effective than the machete weeding, as the machete weeding resulted in new growth of ferns fronds which quickly overgrew the post-treatment vegetation. Meanwhile, the authors found that removal of ferns and disturbing the soil (till and root removal treatments) can enhance the colonization of herbs, shrubs, and trees. Species richness, diversity and percent cover were highest in the intermediate soil-disturbance treatment (the root removal treatment). The authors recommend that with root removal treatments, the authors also recommend additional techniques for collecting and redistributing soil (in areas with fire) or mixing surface and subsurface soil (in areas without fire) to return and expose tree and shrub seeds that could germinate.