Nghe An Prov., Ky Son Distr., Na Ngoi Municipality, north-eastern slopes of Phu Xai Lai Leng mountain system. Primary very humid broad-leaved forest with Cunninghamia konishii as emergent on steep mountain slopes composed of gray shale at elevation 2100-2200 m a.s.l. around point 19°13’52.9’’N 104°05’30.5’’E. Terrestrial sedge in open plase on very steep slope. Common.