Degraded forest in and around Gunung Leuser National Park (SPTN V Bahorok) administratively located in Batu Jonjong – Sopo Padang Village, Bahorok District, Langkat Region, North Sumatra. The overall national park covers 950,000 hectares with 40% of the park in mountainous regions over 1,500 meters in elevation. The Park is part of the Leuser Ecosystem and is surrounded by a several kilometer buffer zone that provides a gradient between totally protected land (national park) and intensively used land.


OURF/Yayasan Sumatra Hijau Lestari (YSHL) or Sustainable Green Sumatra Foundation

Borneo Ourangutans


To support the restoration of indigenous trees within this vital ecosystem to serve in the protection of the watershed and habitat for numerous endangered species, including orangutans, siamangs, tigers, and hornbills.

Deforestation Borneo Orangutan Foundation Borneo


Forest ecosystem recovery or restoration activities aim to restore the land’s structures and functions according to or close to the initial conditions. In this case, we are restoring the native forest communities and buffer zone functions that existed before deforestation occurred.

Biological benefits that buffer zones provide include providing a filter or barrier against human access and illegal use of the strictly protected core zones or conservation area; protection of strictly protected core zone or conservation area from invasion by exotic plant and animal species; providing extra protection against storm damage, drought, erosion and other forms of damage; extending the habitat and thus population sizes of large, wide-ranging species in the protected area (Sayer, 1991).

Innovative forestry methods have been developed to enable trees to be established successfully and economically in this hostile environment. By implementing some very simple and logical techniques, this can now be achieved consistently.



The original forest ecosystem has been lost due to deforestation. Local farmers have historically converted forested portions of the buffer zone and/or encroached into the national park and planted cash crops such as rubber and oil palm.



We have chosen primarily endemic trees that enhance the greatest overall benefit to this region. These tree species are selected specifically to represent those from the reference forest near the restoration area Parkia speciosa, Archidendron pauciflorum, Durio spp., Shorea spp., Syzygium polyanthum, Ficus spp., Litsea irianensis, Canarium grandiflorum.


Actions & Results

  • Our partners. YSHL, are negotiating a Memorandum of Understanding (MoU) with the Forestry Department regarding monitoring and tree-planting activities in Gunung Leuser National Park. This MoU is used as a legal umbrella in the implementation of their activities in the area of Gunung Leuser National Park.
  • Targeted tree planting activities leading to forest and buffer zone restoration will be carried out in collaboration with the forest farmers groups within this region of N. Sumatra. Specific regions will be selected and a plan of tree planting activities will be scheduled within the work plan of YSHL’s Community Education and Conservation Program (CECP). OURF will administer the funding to YSHL over the next 5 years.