Fujian cypress and two other threatened tree species in three conservation zones of a nature reserve in north-western Vietnam

Background Fujian cypress ( Fokienia hodginsii ) is a highly valued but endangered tree species. The Ta Xua Nature Reserve in Vietnam is one of its main conservation centers. This nature reserve consists of a fully protected core zone, a buffer zone in which low intensity forest use is permitted, and a forest restoration zone in which forest regenerates after shifting cultivation. Methods The community and population status of F. hodginsii and two other threatened tree species ( Aglaia spectabilis and Quercus platycalyx ) were assessed across the three conservation zones. Based on 120 random sample plots of 400 m 2 , we applied adaptive cluster sampling for trees with a diameter at breast height (DBH) of at least 6 cm. In addition, tree regeneration (DBH