N. Vietnam, Prov. Bac Can, limestone mountain pass Gio on car road from Hanoi to Cao Bang sity near Ngon Son town at 800-900 m alt. Secondary shrubs and grass communitys on high limestone massif. Shrub up to 2 m hg on open steep grassy mt. slope. Flowers white. Very common. VH 4992 28.05.1997 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5803-96)