parasitizing resources as, e.g., mistletoes do. Others live on the ground, often, in shaded places. Almost all the species rely heavily upon mycorhizal associations with various fungi that decompose surrounding matter, freeing up water-soluble nutrients. Most orchid seeds are extremely tiny, with no food reserves, and will not even germinate without such symbiosis to supply nutrients in the wild. Techniques have now been devised for germinating seeds on a nutrient-containing gel, eliminating the necessity of the fungus, and greatly aiding the propagation of rare and endangered species.
It is in their reproductive methods that orchids truly shine. The Paphiopedilums (Lady Slippers) have a deep pocket that traps visitors, with just one egress, which leads to pollination. A Eurasian genus has flowers that look so much like female bumble bees that males flying nearby are irresistibly drawn in. An underground orchid in Australia never sees the light of day, but manages to dupe ants into pollinating it. The Masdevallia stinks like a rotting carcass, and the forest flies it attracts assist its reproduction. A species Darwin discussed briefly actually launches its viscid pollen sacks with explosive force. Some Phalaenopsis species in Malaysia use subtle weather cues to coordinate mass flowering.
There are a great number of tropical and subtropical orchids, and these are the most commonly known, as they are available at nurseries and through orchid clubs across the world. There are also quite a few orchids which grow in colder climates, although these are less often seen on the market.
One orchid is used as a foodstuff flavoring, the source of Vanilla see below. The underground tubers of terrestrial orchids are used in the manufacture of ice cream in Turkey. With these exceptions, orchids have virtually no commercial value other than for the enjoyment of the flowers (see also Botanical Orchids, below).
A selection of Orchid genera follows:
Aerangis[?]; Aerides[?]; Anacamptis; Angraecum; Anguloa[?]; Ascocenda[?]; Barkeria[?]; Bletilla[?]; Brassavola[?]; Bulbophyllum; Catasetum[?]; Cattleya[?]; Cirrhopetalum[?]; Coelogyne[?]; Cymbidium[?]; Cypripedium[?]; Dactylorhiza; Dendrobium[?]; Disa[?]; Dracula; Encyclia[?]; Epidendrum[?]; Epipactis[?]; Eria[?]; Eulophia; Gongora[?]; Goodyera[?]; Gramatophyllum[?]; Gymnadenia; Habenaria[?]; Herschelia[?]; Laelia[?]; Lapanthes[?]; Liparis[?]; Lycaste[?]; Masdevallia; Maxillaria[?]; Miltonia[?]; Mormodes[?]; Odontoglossum[?]; Oncidium[?]; Ophrys; Orchis[?]; Paphiopedilum[?]; Phalaenopsis[?]; Phragmipedium[?]; Platanthera[?]; Pleione; Pleurothallis; Renanthera[?]; Restrepia; Rhynchostylis[?]; Saccolabium[?]; Sarcochilus[?]; Satyrium[?]; Serapias[?]; Spiranthes[?]; Stanhopea[?]; Stelis; Sophronitis[?]; Stanhopea[?]; Trias[?]; Trichoglottis[?]; Vanda; Vanilla; Zeuxine[?]; Zygopetalum[?].