Pterocarya tonkinensis

The main threats to Pterocarya tonkinensis are the destruction and artificialization of river banks for human activities (e.g. agriculture and urbanization). Furthermore, the species is still an important timber tree for local communities in many regions (Kozlowski et al. 2018). Natural regeneration of the species via seeds seems to be low and few young seedlings are generally present in the field. Any alteration of the water level and absence of flooding episodes could also represent a threat to the species, unfortunately those changes are often necessary, when industrializing rural villages and communities. The construction of dams and containment of small rivers will likely impact strongly the last remaining subpopulations situated outside protected reserves. There are only 20 known subpopulations for this species, but it is possible that other stands still exist as the distribution range of the species has not yet been fully explored by botanists. It is also possible that some stands have been determinated as P. stenoptera could be in fact P. tonkinensis.

The species is not common in cultivation in botanic gardens and public parks. The species is held in at least 10 collections from across the globe (BGCI 2019). Field explorations are still necessary to precise the distribution of the species, especially in Lao PDR and at the border between China and Viet Nam. It is also urgent to start monitoring the remaining stands of the species. An ex situ conservation program should also be initiated, to preserve the genetic diversity of the species in botanic gardens and arboreta in the countries of origin of the species.