Friday, 4 September 2009

Common Twayblade




Common Twayblade (Neottia ovata)

Perhaps the Common Twayblade has a Nordic origin, courtesy of Nordic invaders, to its name with its current name in Swedish being TvĂ„ Blad meaning the same as the English word Twayblade – two leaves. This plant has two leaves clasping the base of the flower stem, or sometimes just two leaves present where there is no flower stem. Occasionally you might find the odd plant with three to five leaves, much as you might find a four-leaved clover. The stem is hairless below the two main leaves and lightly downy above the leaves. If you catch this plant early in the morning or late in the afternoon these tiny hairs give it a golden halo. Technically there are a few very small leaves higher up the stem above the main pair.

The Common Twayblade flowers from late April until early August. It is called Common because it is so widespread throughout Britain. Its wide spread is due to its resilient and adaptable nature. It does not occupy one specific habitat type and can be found in most habitats from woodland, grassland to dune slacks. Two common features in its distribution is that grows predominantly on calcareous substrates and will only tolerate mildly acidic soil. It also grows in areas that are relatively undisturbed – ancient woodland, unimproved grassland, heathland etc. Despite its wide distribution this plant is currently absent from 30% of its historical range, which would seem to be linked to the general loss of habitat that has occurred.

The flowers are the kind which a lot of people pass by unless directed to look more closely. The flowers are small and greenish, on closer inspection they are clearly shaped like a small person. The plants can be found singly or in dense clumps. These clumps arise from vegetative reproduction where shoots from the rhizomes develop into new plants. It takes from 7 to 20 or more years for a plant to reach maturity from seed. This slow developing is accompanied by longevity, plant have been known to exceed 40years of age. The flowers are so small that they can only be pollinated by small insects. Attracted by nectar these insects set of a sensitive trigger mechanism in which rapid secretion of a sticky quick drying liquid which sticks the pollinia onto the insect. This mechanism is highly efficient and results in high rate of seed setting.

This year I found Common Twayblades growing in ancient woodland at the base of the North Downs above Wye in Kent. Last year I saw them growing around pitches on a campsite in woodland in the Lake District and 6 weeks later in dune slacks on the north coast of Scotland.

3 comments:

domgreves said...

Looks like being a very fine year for them in the Surrey Hills.

Ged Davis said...

I have found a group of Twayblade growing under a Beech Tree in Richmond but it has purple flowers, have I made the right id? Ged

Susanne said...

Twayblade flowers can have a reddish tint. If you have a photo you can email it to me on info (at) susannemasters.com or try using this orchid identification guide to check what you saw http://www.nhm.ac.uk/content/dam/nhmwww/take-part/Citizenscience/orchid-observers/orchid-observers-id-guide.pdf