In Robinson Crusoe Island 860 ha are invaded by a compact vegetation layer of only two species, Aristotelia and Rubus introduced shrubs. This area constituted 37% of vegetation surface in Robinson Crusoe. The abrupt frontier between the endemic forests and invasive shrubland is not immovable. The invasive shrubland advance moving this frontier, knocking the native trees in the border and probably changing the environmental conditions necessaries to maintain the endemic forests. Furthermore, in places with high slope these invasive species have a positive impact stopping the erosion. The remotion of Aristotelia and Rubus from these areas is very difficult, due to danger to create erosion and by the aggressive vegetative re-routing of invasive species from the adjacent areas.

In this project we will develop a technique to exclude invasive plants in the frontier of the endemic forest with the compact layer of invasive plant avoiding an erosion problem. We will identify a border of plant invasive-endemic forest´ area with different characteristics of slope (low, medium and high) and will develop in this area a essay of mechanical remotion of Aristotelia and Rubus. The remotion will begin from the forest toward the shrubland vegetation layer. In the essays we will remove ten to fifteen rectangles of 50 (low slope), 40 (medium slope) and 25 (high slope) m of invasive adult plant against the slope x 50 m along the slope. Between each essay a strip of around 6 meters of plant invasive will be kept in order to stop the erosion along of the essays. The soil characteristic (compaction, water retention and presence of michorrizas) will be measured after the remotion will be done, in order to understand how the plant invasive, modify the soil properties. After the remotion, ferns from adjacent areas will be moved at the naked soil. The ferns grow very fast and cover easily the soil preventing the seed germination of invasive plant, which seeds could be deposit in the next fruiting season. The aggressive re-routing from the new frontier will be monitored each five months and eliminated mechanically.

After five and ten months of the essay we monitored the re-routing of invasive species, the success of establishment of ferns and water retention in areas with ferns and areas with invasive species with similar slope. If the essays are no success in stopped the erosion, these will be improved; may be, changing the form and area of the rectangles, by a next experience.