An annual or biennial herb of arable field margins and bare tracks on calcareous soils, and on open chalk downland. Its seeds are long-lived and this has led to its reappearance following disturbance at some sites. Lowland.
Known as a British plant since 1551, A. chamaepitys has declined considerably over the past fifty years due to herbicide spraying, abandonment of fallow land and succession to coarse grassland, scrub and woodland on chalk slopes. It has benefited from conservation management at some sites.
European Southern-temperate element.
Count of 10km squares in Great Britain: 43
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 0
Atlas Change Index: -0.62
RDB Species Accounts
Ground pine, Palf y Gath Bali
Status in Britain: VULNERABLE. WCA Schedule 8.
Status in Europe: Not threatened.
A. chamaepitys was familiar to the Tudor herbalists who thought that it and Teucrium botrys were one and the same species, the former being male and the latter female. It is an attractive plant with intense yellow flowers and a strong resinous scent when crushed or trampled. Characteristic habitats include the upper edges of cultivated fields, crumbling banks and track sides, ground disturbed by scrub removal, road works or pipe-laying operations, and the edge of chalk or gravel pits. Dry sun-baked slopes are favoured, particularly on chalk escarpments. It is a poor competitor, confined to bare ground and the earliest seral stages. It used to be a characteristic member of the flora of temporary arable or fallow fields on the chalk downs of Surrey and Kent. Though it is no longer a typical arable weed, it sometimes still occurs with Filago pyramidata, T. botrys and other rare species on ploughed field edges that have escaped herbicide spraying. A. chamaepitys also occurs in semi-natural calcareous grassland, generally on the steepest, hottest part of the slope, and on bare soil scratched by rabbits. It may grow on bare chalk or chalky clay, but more typically prefers a thin surface layer of sandy or gravelly drift. Commoner associates include Arenaria serpyllifolia ssp. leptoclados, Euphorbia exigua, Kickxia spuria, Sherardia arvensis and Veronica persica.
The flowering period is unusually long, extending from June to October, depending on whether the seedlings are autumn-, winter- or spring-germinated. Autumn-germinated plants survive the winter as rosettes. Although frequently thought of as an annual, some robust plants are plainly short-lived perennials with a woody tap-root. A. chamaepitys is said to be vulnerable to cold, wet, prolonged winters, which kill off the autumn-germinated seedlings. There is also evidence that seeds fail to ripen in cold summers (Grubb 1976). It may owe its survival here at the northern edge of its range to the flexible seed germination strategy, which may be genetically controlled.
A. chamaepitys can survive for many years as dormant seed, in places up to half a century. This helps to explain its erratic appearances, flowering prolifically after sudden disturbance, and then disappearing again as the vegetation closes. On nature reserves it can be induced to flower annually by shallow ploughing or rotavating. This species has become much less frequent during the past 50 years, partly because of the use of herbicides, but more because of the abandonment of fallow land on chalk slopes, and the spread of coarse grass, scrub and secondary woodland on its downland localities. It is particularly vulnerable at the outlying parts of its British range in Hampshire and the Chilterns where only a few sites remain; less so on the North Downs in Surrey and Kent where new sites are still being found. Most of the known populations are small, however, and the species now often depends on conservation management to survive. Exceptionally, a population may number more than 1,000 plants. The improved level of scrub control and the restocking of some old sites with sheep are hopeful signs, as is the possible prospect of hotter, drier summers.
Outside Britain, A. chamaepitys occurs across central and southern Europe, usually on light calcareous soils. Its distribution extends eastwards into the Levant and southwards to North Africa.
P. R. Marren
Scarce Atlas Account
Ajuga chamaepitys (L.) Schreber
WCA Schedule 8 species
Typically this is a species of open chalk downland habitats in southern England, most often on arable field margins but occasionally in open grassland sites. Where it does occur as an arable weed, it is usually indicative of a site that has escaped the normal intensive farming regime, and it is often associated with other rare species such as Filago pyramidata or Teucrium botrys. This lowland species appears to favour the top end of a south-facing slope, where the soils are more freely draining and warmer, and where there is usually less competition from the crop itself. The plant benefits from the activity of rabbits in reducing the crop canopy and opening up areas by scraping. In chalk grassland it also colonises areas disturbed by rabbits or human activity.
A. chamaepitys is an annual or biennial. Its main germination period is in the autumn (August/ September), with a further flush from January to February. It is vulnerable to cold, wet, prolonged winters which kill off autumn-germinated seedlings. This may help to explain its sporadic appearance in its regular sites. In cold years the seeds fail to ripen (Grubb 1976). The seed can remain dormant for some years.
This plant is at the northern limit of its range in Britain, and is restricted to south-east England by its requirements for warm calcareous soils. It has declined considerably under the impact of modern intensive farming regimes: it cannot compete effectively in enriched soils and is susceptible to herbicide treatments. In some areas it is now more frequent in disturbed areas, such as places where trees have been uprooted or pipelines laid, than on arable margins. This species has become so scarce in many of its sites that it is now listed on Schedule 8 of the Wildlife and Countryside Act (1981). At some sites it is encouraged by a programme of regular ploughing or scraping of turf. The introduction of low intensity arable regimes (such as ‘conservation headlands’) on remaining sites would enhance its prospects of survival.
Found throughout Europe except for the far north, it has declined considerably in northern and western Europe. Its distribution extends eastwards into the Lebanon and Palestine, and southwards into North Africa.
A. chamaepitys has been known to persist at some sites for more than a century, and to recur in these sites after a period of time in which plants were not found, usually after a deep plough.
PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.