FLORA OF VIETNAM
Orchidaceae
Dendrobium williamsonii Rchb.f.

N. Vietnam, prov. Ha Giang, distr. Meo Vac, municipality Sung Chang, vicinities of Lu Lu Phin village (N 23°11′ E 105°18′). Primary mixed mossy semideciduous open forest (with domination of Pseudotsuga brevifolia and Tsuga chinensis) along tops of karst remnant limestone ridge at 1350-1400 m elev. Epiphyte. Flowers: tepals light yellowish-white, lip yellowish white with reddish-orange center, column white, anther yellow.
CBL 1852 29 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)
Collectors: P.K.Loc, P.H.Hoang, Averyanov L.