FLORA OF VIETNAM Orchidaceae Dendrobium longicornu Lindl.
Border area between Phieng Luong municipality (Ha Giang Prov., Bac Me Distr.) and Sinh Long municipalitiy (Tuen Quang Prov., Na Hang Distr.).
Primary broad-leaved humid evergreen and mixed forest on very steep slopes and along rocky ridge composed with solid crystalline highly eroded limestone at elevation 1100-1170 m a.s.l. around point 22°38′24.3″N 105°20′21.3″E.
Epiphyte on mossy trees on rocky ridge edge. Common.