In the forest-savannah mosaic zone of the Centre-Cameroon region, studies based on remote sensing data, surveys and botanical records reveal a trend towards transgression of forest onto savannah as a result of anthropogenic management. By planting defensive hedgerows of Ceiba pentandra and Bombax buonopozense at the end of the 19th century, the people of the Yambassa village at the confluence of the Mbam and Sanaga rivers created favorable conditions for the establishment of pioneer species from dense forest to savannah. Once established, thanks to the suspension of bush fires in the savannahs, these species spread out by associating with fruit trees introduced by man to create groves and forest islands. Initially set up as defense systems against enemies, hedgerows have over time become firebreaks and dispersal corridors for forest species. Recently, local people have also taken advantage of the shade provided by the hedgerows to plant agroforests on either side, with cocoa trees and fruit trees such as oil palm, etc.