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Plant Focus

A guest post by Matt Candeias, host of the In Defense of Plants podcast and blog

Rescuing Plant Species with Extremely Small Populations in China: the Case of the Xichou oak, Quercus sichourensis

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Weibang Sun, Zhekun Zhou, Wenyun Chen, Yuan Zhou, Lei Cai, Murphy Westwood, and Jessica Turner

Published May 2016 International Oaks No. 27: 163–170


The new concept of PSESP (Plant Species with Extremely Small Populations), developed for rescuing some of the most globally threatened plant species, was first suggested in Yunnan, China in 2005, and is now widely accepted. Currently, several national and regional-level conservation strategies and actions (120 species targeted by the State Forestry Administration and National Development & Reform Commission of China, and 62 species listed by the Yunnan provincial government of China) have been implemented in China. The Xichou Oak, Quercus sichourensis, (Hu) C.C. Huang & Y.T. Chang was selected as a pilot PSESP taxon for a project entitled, “A Pilot Program for Conserving Yunnan’s PSESP” in October 2011. Recent comprehensive surveys for this oak revealed that only 3 localities with a total of 11 mature trees are known in Southeast Yunnan (10 trees) and Southwest Guizhou (1 tree). As a case study, this paper will give a detailed introduction to the current actions that have been implemented to rescue the Xichou Oak.


PSEP, conservation actions, extremely threatened species


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