FLORA OF VIETNAM Orchidaceae Dendrobium thyrsiflorum Rchb.f.
N.Vietnam, Ha Tinh Prov., Huong Son Distr., Son Hong Municipality, around point 18°34′06′'N, 105°11′40′'E. Heavily logged primary broad-leaved evergreen dry forest on steep mt slopes and along ridge composed with shale at elev 250-300 m a.s.l.