The common name orchid is a shortened form of its Latin family name Orchidaceae. There are about 28,000 currently accepted species world wide. Genetic sequencing indicates orchids may have arisen 76 to 84 million years ago if not earlier.
In Britain we have 57 native species, some are surprisingly common and widespread, while others are sought after rarities found only in a few select places. One of the things about orchids is their immense variability, even within species, which can makes accurate identification extremely difficult.
Orchids reproduce in a number of ways. Many are pollinated by insects, which they attract by shape, colour and smell. With these insect pollinated species we have the added difficulty in that they can produce hybrids. The resulting plants often display characteristics that are unlike either parent plant, making identification problematic. Others are self pollinating and a number reproduce by producing offshoots or plantlets formed from one of the nodes along the stem.
Orchid seeds are very small – when they are spread by the wind, they need to land somewhere that has ideal conditions of light, moisture and warmth. Orchids also need to be infected with a mycorrhizal fungus from the soil if they are to survive. The fungus attacks the orchid which breaks down the fungal cells and derives the soil nutrients which it is unable to obtain for itself. Once the plant grows leaves and is able to produce energy through photosynthesis (producing energy from sunlight). There are, however, some species that remain dependent on a relationship with fungi throughout their lives and these are the ones that lack chlorophyll (the green colouring in leaves) without which they cannot make food through photosynthesis.
British Naturalists' Association
27 Old Gloucester Street,
London, WC1N 3AX