Research was carried out on four threatened tree species across north and south Sudanian phytogeographical zones in Burkina Faso. A quantitative inventory of regeneration populations was completed and sapling dynamics were monitored through surveys of survival and growth in permanent plots. Laboratory and nursery experiments were carried out to test germination and the performance of transplanted seedlings. Results revealed difficulties that saplings faced during their development. In natural stands of Sterculia setigera and Afzelia africana, saplings were rare or irregularly distributed. A greater number of individuals of Bombax costatum were observed, which was the only species with significant density variation between phytogeographical zones (p= 0.021). Size class showed irregular population structures. A high mortality between the first and second year …