Wood calamint  (Clinopodium menthifolium)

Classified as Endangered in Great Britain (3) and fully protected under Schedule 8 of the Wildlife and Countryside Act, 1981 (3).

Wood calamint produces pink or purplish-pink flowers, which measure 15 to 22 mm in length, and have two 'lips' of fused petals that are often speckled with darker pink spots (2). The flowers are arranged on flower spikes in whorls. The plant is covered in fairly long hairs, and has dark green oval-shaped leaves. When the leaves are crushed they give off a distinct minty aroma (2).

Rare in Great Britain, since 1843 this plant has been found only in a single dry chalk valley on the Isle of Wight (4) where it currently has an extremely restricted distribution of a just few square meters (3). In Europe it is known from most countries, but it does not reach into Scandinavia (3).

You can view distribution information for this species at the National Biodiversity Network Gateway.

Grows in lightly-shaded conditions at the edges of woodlands and in scrub, on chalky soils (4).

This perennial species flowers from July to October, and can spread by means of thin stems called 'rhizomes' that pass along the surface of the soil, from which new plants sprout and roots become established (2). This form of reproduction is known as 'vegetative reproduction'. Wood calamint can also reproduce by seeds; four small 'nutlets' (single-seeded fruits with a tough woody coat) are produced by each flower, these fall to the ground when they are ripe (2).

Wood calamint was once fairly abundant at its single location, but the decline in coppicing in the 1940s resulted in a drastic decline, which has been halted recently by the reintroduction of coppice management (4). Competition with aggressive species is the biggest threat currently facing this plant (3).

Measures to conserve wood calamint have been in operation since 1962, when just five plants survived (3). Hazel trees have been coppiced and ground cover has been cleared at the site, which has been designated as a Site of Special Scientific Interest (SSSI) (3). Furthermore, invasive plants and tall herbs such as the nettle (Urtica dioica) have been removed (4). The species is still endangered despite these efforts, however, and at present the population is estimated to number in the low hundreds (3).

There may be further information about this species available via the National Biodiversity Network Gateway.