Greek dendros – tree; bios – life; an allusion to the epiphytic habit of most species.
Epiphytic, epilithic or rarely terrestrial herbs, sympodial, with or without rhizomes. Stems cane-like or thickened into pseudobulbs, sparse or dense, green. Leaves apical or along stems, 1-many, thin to leathery, mostly stalkless. Inflorescences terminal or lateral racemes, erect to pendent. Flowers resupinate, 1-many, small to large, variously coloured. Sepals similar, dorsal free, laterals fused to column foot forming a chin-like extension (mentum). Petals larger or smaller than sepals, free. Labellum entire or 3-lobed, joined to column foot and sometimes to base of lateral sepals forming a spur. Column usually short, toothed at tip, with a long foot. Pollinia 4, in 2 pairs.
Dendrobium, as it stands currently, consists of several distinct segregate groups, either regarded as sections within the genus or as separate genera. Brieger (1981) described many new genera, most of which have not generally been accepted in the subsequent literature, although many are readily defined and easily recognised. New combinations were made in Dockrillia Brieger (= Dendrobium section Rhizobium Lindl.) by Clements and Jones (1996), to accommodate the so-called 'terete-leaved' species; in Grastidium Blume (= Dendrobium section Grastidium (Blume) J.J. Sm.) by Clements and Jones (1996 and 1997); and in Eriopexis (Schltr.) Brieger (= Dendrobium section Eriopexis Schltr.) by Clements and Jones (1997).
Dendrobium remains an enormous and diverse genus with many species commonly grown as ornamentals, the popularity of these changing constantly with time. It is beyond the scope of this work to provide a comprehensive key to, and decriptions of, all species popularly in horticulture as this would run to well over 250 species. Instead, a key to the main sections and descriptions of a few representative species are provided.
About 1400 species from India, China, Japan, SE Asia, New Guinea and Australia.
Chin-like extension at base of flower.
Cribb, Reeve & Woods (1985), Cribb (1986), Reeve & Woods (1989), Schelpe & Stewart (1990), Lavarack et al. (2000).
Source: (2005). Orchidaceae. In: . Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.