Dendrobium wentianum J.J.Sm., Bull. Dép. Agric. Indes Néerl. 45 (1911) 6; Nova Guinea 8, 3 (1911) 573, t. 95B.
Type: Nouhuys, van 4 (holo BO).
(Roots thick.) Stems flexuose, (pendulous), branching, to c. 65 cm long, internodes 0.7-1 cm long. Leaves (reflexed,) ovate, 1.8-3.4 by 1.1-1.8 cm, thick coriaceous, apex obtuse. Inflorescences lateral, racemose, 1.25 cm long; peduncle 0.6 cm long, 2-3-flowered. Floral bracts cucullate-ovate, to 0.9 cm long, apex acuminate. Pedicel and ovary 2.3 cm long, sigmoid, 6-ribbed, the ribs paired. Flowers 2.7 cm long. Dorsal sepal oblong-ovate, 1.43 cm by 7 mm; mentum curved, 1.7 cm long, obtuse. Petals narrowly oblong, 1.4 cm by 5 mm. Lip clawed, spathulate, when flattened 2.35 by 1.6 cm, base claw for 0.53 cm adnate to the column-foot, apex cucullate, margins densely short-laciniate, apex emarginate. Column 0.6 cm long; column-foot 1.7 cm long.
(after Smith, 1911 & 1916).
Colours: Not described for the type collection, flowers now known to be uniformly bright orange, sometimes tinged red. The roots have orange tips.
Habitat: Epiphyte in montane forest, often on trunks of Nothofagus. Altitude 1850 to 3250 m, mainly above 2500 m.
Flowering time in the wild: February, April-August, October.
Distribution: New Guinea (endemic).
Distribution in New Guinea: Papua (Jaya Wijaya Regency); Papua New Guinea (Sandaun, Southern Highlands, Enga, Western Highlands, Eastern Highlands, and Central Provinces).
Notes: Dendrobium wentianum is a common, widespread and variable species from the high mountain forests. It may be recognised by the thick, branching, pendulous stems, with relatively broad, reflexed leaves, and uniformly orange flowers.
Cultivation: Cool growing epiphyte, keep in shade.