Ground pine (Ajuga chamaepitys)
|Size||Height: 5 - 22 cm|
Classified as Vulnerable in the UK only.
The ground pine is a small, greyish-green plant, which takes its name from its resemblance to a pine seedling. It also smells like its un-related namesake when the foliage is trampled or crushed. It bears yellow, red-dotted flowers in ones or twos up the stem and amongst the hairy, much divided three-lobed leaves.
It was a plant well known to Tudor herbalists who probably exploited the resins contained within the leaves. They also considered the ground pine and the similar cut-leaved germander, sometimes found growing nearby, to be male and female examples of the same species.
The ground pine ranges across central and southern Europe to the Mediterranean and into North Africa. In the UK it is confined to scattered sites in the South-east of England, in Hampshire, Kent and Surrey, and in the Chilterns.
This species likes disturbed, bare ground, preferring south-facing, dry hillsides on chalk. It occurs on the edges of cultivated fields, tracksides, and crumbling banks. It can also be found growing on areas that have been broken up by construction works.
The ground pine uses a double-flowering strategy. It can flower at any time from June to October, depending on the time of seed germination. A proportion of its seeds from any spring will germinate in autumn, but some will also germinate the next spring if protected from winter frosts. Even when suitable growing areas are prepared, the plant does not readily occupy these because it has no known mechanism for spreading, other than dispersal by rabbits, stock or human disturbance, but just fortifies itself in small colonies, rarely more than a few hundred square metres in area.
Although it is considered to be an annual plant, it occasionally behaves as a short-lived perennial. It is a non-competitive species, but the seeds can lay dormant for at least 50 years, possibly longer, and may germinate when the soil is disturbed. The species spreads very slowly, but can hang on in established sites and bloom again after some considerable time when the right conditions allow.
The plant itself contains a cocktail of unpleasant chemicals that make it very unattractive to herbivores, and most learn not to eat it. It is optimised for warm, dry environments with very narrow, thick-skinned leaves that minimise water loss from evaporation.
The Ground Pine is a plant that is very particular in its choice of habitat. Many of its former sites are becoming inhospitable as a result of changes in agricultural practices, the encroachment of scrub and other dominant species, which inhibit germination, and increasing use of herbicide spraying.
Regular disturbance of the ground is critical, and in many cases this is not taking place, even where its seeds may be lying.
The concern over the status of the ground pine has led to its inclusion on the UK Biodiversity Action Plans. In partnership with Plantlife, the wild plant conservation charity, English Nature has funded work on this species through their Species Recovery Programme.
Plantlife has mapped out all the known ground pine sites and liaised with landowners to encourage the sympathetic management of this plant. Several of the sites are Sites of Special Scientific Interest (SSSIs), and Plantlife carried out yearly surveys at the 15 sites known to hold populations. Scrub-clearance and deliberate soil disturbance by ploughing was also undertaken and this has had a positive effect on the populations of the ground pine.
A number of sites owned by Kent County Council have been managed in the same way, and further objectives are to try and recruit volunteers to manage all sites supporting the plant and conduct further research into its biology.
As a result of this work, the programme has moved into a Post Recovery phase, which declares that the species is maintaining itself - with the appropriate management and necessary ground disturbance - on a long-term basis as a viable component of its natural habitats. The natural range of the ground pine is no longer being reduced and is unlikely to be threatened in the foreseeable future.
It is now important that the populations at the various sites are maintained and secured from damage. Five further sites have been earmarked for a re-introduction programme to be completed by the year 2007.
Information supplied by English Nature.
- Annual: lives or grows for just one year.
- Colony: a group of organisms living together, individuals in the group are not physiologically connected and may not be related, such as a colony of birds. Another meaning refers to organisms, such as bryozoans, which are composed of numerous genetically identical modules (also referred to as zooids or 'individuals'), which are produced by budding and remain physiologically connected.
- Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.