Northern Vietnam, Lao Cai Prov., Van Ban Distr., to the west of Nam Xay village (around point 21°59′00′'N, 104°02′00′'E). Secondary broad-leaved evergreen submontane forest with bamboo on granite and quartzite very steep slopes at elev. 700-900 m a.s.l. Deciduous tree up to 25 m hg. Flowers dirty violet. Common. Usual co-dominant of the secondary forests at 900-1000 m a.s.l.