Rumex rupestris

Last updated

Rumex rupestris
Rumex rupestris.JPG
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Caryophyllales
Family: Polygonaceae
Genus: Rumex
Species:
R. rupestris
Binomial name
Rumex rupestris
Le Gall

Rumex rupestris, commonly known as shore dock, is a species of flowering plant belonging to the family Polygonaceae. [1] Its native range is Western Europe [1] and is one of the world's rarest dock species. [2]

Contents

Description

Rumex rupestris is a coarse stout woody perennial measuring 30 – 50 cm (sometimes up to 70 cm) in height, with one or two shoots arising from the stock. The thick, dull bluish green leathery basal leaves are 10 – 30 cm long with entire, undulate leaf margins. They are oblong or broadly ovate-lanceolate shaped, narrowing rather abruptly to a truncate or subcordate base. The petiole is less than one third the length of the leaf blade. The stem leaves are oblong-lanceolate that gradually narrow to the base, with an acute leaf tip at the leaf end. The leaf margin is undulate, crenulate and subsessile. [2]

The inflorescence comprises a dense panicle with ascending branches, usually making an angle of about 45 degrees with the main stem. The branches have numerous short crowded branchlets and 5 - 20 whorls of densely packed flowers. [2]

The valves or tepals are blunt and entire, each measuring 3 – 4 x 2 – 2.5 mm. Each valve bears a very swollen smooth elongate tubercle that occupies over 2/3 of the valve length, and almost the entire width. [2] These swollen tubercles are the critical feature distinguishing the species from similar species such as Rumex conglomeratus with considerably smaller tubercles. [3] Vegetative identification of R. rupestris is difficult and needs confirming when the plant is in fruit (PlantLife). The nut is reddish brown and trigonous, measuring about 2 x 1.5 mm and with acute angles. It is broadest near the rounded base and abruptly acute at the tip. [2]

Distribution and habitat

Rumex rupestris is a European endemic restricted to small, scattered populations across the Atlantic coasts of western Europe. Its known distribution covers coastal areas of Anglesey, south Wales, south-western England, the Channel Islands, through France to Galicia and northern Spain. [2] [4] It was reported to be locally common on the Isles of Scilly, but more recently it is thought it may be extinct there. [2] [5]

Shore dock grows at or just above mean high-water mark in low-altitude (up to 60 metres (200 ft)) coastal habitats, always with a constant supply a freshwater and in the presence of bare ground created by coastal erosion. The habitats typically include damp cliff edges or bases, seepage zones and wave-cut platforms. More rarely, the plant grows in dune slacks and on sand or shingle beaches, as well as bedrock crevices with a submerged supply of freshwater from springs. It does not appear to have specific soil requirements and can grow in soil-free fissures in sedimentary or metamorphic rocks, as well as fine blown sand and shingle. [3]

Ecology

R.rupestris occurs in very small localized populations often comprising fewer than 10 individuals per site, growing either separately or in small clumps. [4] Populations occupy small areas of suitable habitat usually covering less than 1m2 and rarely extending beyond a few square meters. [6] Although this plant occurs only in very small, scattered colonies, these could be functioning as components of larger metapopulations in the wider landscape. [6] The floating fruits are dispersed by sea wave action, which potentially enables the plant to colonize new areas along the coast (PlantLife). However, due to the dynamic nature of the coastal environment where it grows, R. rupestris individuals that do become newly established in a small area of suitable habitat may survive for only one or a few years before being eradicated. Nevertheless, individuals occasionally reappear in sites from which they previously disappeared. [4]

Rumex rupestris is a poorly competitive pioneer species favouring bare ground. [7] It is susceptible to out-competition from other vigorous perennials such as Phragmites australis and Rubus fruticosus and is therefore dependent on regular coastal erosion and physical habitat disturbance for suppression of stronger competitors, thereby allowing sufficient recruitment to seedlings. The plant can also withstand grazing by cattle, sheep, and horses, and this may provide an ecological benefit by preventing succession from open to closed vegetation. [3]

Threats and human impacts

The plant appears to be vulnerable to human impacts throughout its entire range. Threats include tourism pressures, cliff consolidation, construction of coastal defense works such as seawalls, marine pollution from oil spillage, sewage or fertilizer run-off, and possibly increased storminess through climate change. [3] [4] [8] Coastal protection measures can reduce population both through direct loss of plant colonies and reduced erosion of sites. Nevertheless, shore dock is also vulnerable to population loss through the natural instability of its habitat and relatively small population size [4] as well as habitat encroachment of more vigorous perennials, especially through agrochemical run-offs. [3]

Rarity and protection status

R. rupestris has been included on the Red List and is listed as endangered in the British Red Data Book. [9] It is also protected under Schedule 8 of the Wildlife and Countryside Act 1981, as well as appearing in Annexes II and IV of the European Community Directive on the Conservation of Natural Habitats & Wild Fauna & Flora 1992 [10] and in Annex I of the Bern Convention 1982. [3]

This plant is listed as a priority species within the UK Biodiversity Action Plan and the Cornwall Local Biodiversity Plan. [3] The first full species action plan for shore dock was prepared in 1999, [8] most of which has since been executed by Plantlife, Natural England, the Centre for Ecology and Hydrology, the Countryside Council for Wales, and the National Trust. The ongoing activities ensure that localities with existing populations are monitored, new populations searched for, and the plant's ecological requirements accounted for during land management, developmental control and coastal defense works. [3]

Although it is a rare species, shore dock has a range of life history traits that make it highly adapted to a physically disturbed habitat and harsh set of environmental conditions. [6] For example, it can easily withstand effects of salt from sea spray. However, the physical disturbance of the dynamic environment that allows the plant to persist through exclusion of stronger competitors also prevents significant recruitment from seedlings. This irony may explain the plant's natural rarity. [3]

Related Research Articles

<span class="mw-page-title-main">Sorrel</span> Flowering plant in the family Polygonaceae

Sorrel, also called common sorrel or garden sorrel, is a perennial herbaceous plant in the family Polygonaceae. Other names for sorrel include spinach dock and narrow-leaved dock.

<i>Rumex</i> Genus of plants

The docks and sorrels, genus Rumex, are a genus of about 200 species of annual, biennial, and perennial herbs in the buckwheat family, Polygonaceae. Members of this genus are very common perennial herbs with a native almost worldwide distribution, and introduced species growing in the few places where the genus is not native.

<i>Rumex crispus</i> Species of flowering plant

Rumex crispus, the curly dock, curled dock or yellow dock, is a perennial flowering plant in the family Polygonaceae, native to Europe and Western Asia.

<i>Rumex obtusifolius</i> Species of flowering plant in the family Polygonaceae

Rumex obtusifolius, commonly known as bitter dock, broad-leaved dock, bluntleaf dock, dock leaf, dockens or butter dock, is a perennial plant in the family Polygonaceae. It is native to Europe, but is found on all temperate continents. It is a highly invasive species in some zones, resulting from its abundant seed dispersal, adaptability to reproduce, aggressive roots, ability to tolerate extreme climates, and hardiness.

<span class="mw-page-title-main">Annet, Isles of Scilly</span>

Annet is the second-largest of the fifty or so uninhabited Isles of Scilly, one kilometre west of St Agnes with a length of one kilometre and approximately 22 hectares in area. The low-lying island is almost divided in two by a narrow neck of land at West Porth which can, at times, be covered by waves. At the northern end of the island are the two granite carns of Annet Head and Carn Irish and three smaller carns known as the Haycocks. The rocky outcrops on the southern side of the island, such as South Carn, are smaller. Annet is a bird sanctuary and the main seabird breeding site in Scilly.

<i>Muehlenbeckia complexa</i> Species of flowering plant

Muehlenbeckia complexa is a plant commonly known as pohuehue, although this name also applies to some other climbers such as Muehlenbeckia australis.

<i>Rumex longifolius</i> Species of flowering plant

Rumex longifolius, commonly known as the dooryard dock or northern dock, is a perennial species of plant in the genus Rumex.

<i>Rumex palustris</i> Species of flowering plant

Rumex palustris, or marsh dock, is a plant species of the genus Rumex, found in Europe. The species is a dicot belonging to the family Polygonaceae. The species epithet palustris is Latin for "of the marsh" which indicates its common habitat.

<i>Rumex patientia</i> Species of flowering plant in the family Polygonaceae

Rumex patientia, known as patience dock, garden patience, herb patience, or monk's rhubarb, is a herbaceous perennial flowering plant belonging to the family Polygonaceae. In spring it is often consumed as a leaf vegetable and as a filling in pies in Southern Europe, especially in Bulgaria, North Macedonia, Bosnia and Herzegovina and Serbia. It is also used in Romania in spring broths or sarmale.

<i>Rumex salicifolius</i> Species of flowering plant

Rumex salicifolius is a species of flowering perennial plant in the knotweed family known by the common names willow dock and willow-leaved dock. It is native to much of western North America, and more specifically, in southern and central parts of California, and some parts of Arizona and Nevada. It can also be found in parts of Europe as an introduced species and a roadside weed. It is an extremely variable plant which is generally divided into many varieties, some of which may actually be specimens of other species.

<span class="mw-page-title-main">Godrevy Head to St Agnes</span>

Godrevy Head to St Agnes is a coastal Site of Special Scientific Interest (SSSI) in north Cornwall, England], noted for both its biological and geological characteristics. A number of rare and scarce plant species can be found on the site, along with many breeding seabirds.

<i>Rumex alpinus</i> Species of herb

Rumex alpinus, common name monk's-rhubarb, Munk's rhubarb or Alpine dock, is a leafy perennial herb in the family Polygonaceae. It is native to upland areas of Europe and Western Asia.

Rumex persicarioides is a flowering dicot species in the family Polygonaceae. This species flowers annually in the summer-time but on rare occasions it has been found to be biennial. R. persicarioides is not cultivated for human use and should not be confused with the similarly named genus Persicariae.

<i>Rumex sanguineus</i> Species of flowering plant

Rumex sanguineus, commonly known as wood dock, bloody dock or red-veined dock, is a perennial flowering plant species in the family Polygonaceae. Rumex sanguineus is a dicot and can be observed in Europe with at least two varieties.

<i>Rumex britannica</i> Species of flowering plant

Rumex britannica is a flowering plant species in the family Polygonaceae.(Buckwheat family) (perennial).

<i>Rumex bucephalophorus</i> Species of flowering plant

Rumex bucephalophorus, also known as horned, red, or ruby dock is an annual herbaceous plant that is part of the family Polygonaceae. The scientific name Rumex bucephalophorus was first described and published by Linnaeus in 1753 in Species Plantarum. Other scientific names have also been given to Rumex bucephalophorus such as Bucephalophora aculeata and Lapathum bucephalophorum. R. bucephalophorus is most commonly found in subcoastal or coastal regions, but also are "casual aliens", few and far between, among inland populations. Rumex bucephalophorus is native to the Mediterranean Basin and grows best in areas with little human intervention.

<i>Rumex fueginus</i> Species of flowering plant

Rumex fueginus, known as American dock, golden dock, and Tierra del Fuego dock, is a flowering plant in the family Polygonaceae. Rumex fueginus was first formally named by Rodolfo Armando Phillipi. Rumex fueginus is native from Canada in northern North America to Tierra del Fuego at the southern tip of South America. It has previously been considered a subspecies or variety of Rumex maritimus, a Eurasian species.

Rumex lapponicus, known commonly as Lapland mountain sorrel is a perennial flowering herb species in the family Polygonaceae. It is commonly found in meadows and rock outcrops, as well as montane, arenicolous, and alluvial habitats.

<i>Rumex cuneifolius</i> Species of flowering plant

Rumex cuneifolius is a flowering plant species in the family Polygonaceae.

<i>Viola lactea</i> Species of flowering plants in the family Violaceae

Viola lactea, also known by its common name pale dog violet, is a species of flowering planet of the family Violaceae.

References

  1. 1 2 "Rumex rupestris". Global Biodiversity Information Facility . Retrieved 2024-01-07.
  2. 1 2 3 4 5 6 7 Lousley JE, Kent DH. 1981. Docks and Knotweeds of the British Isles. BSBI Handbook No. 3. BSBI, London.
  3. 1 2 3 4 5 6 7 8 9 PlantLife. UK Biodiversity Action Plan, Rumex rupestris Le Gall Species Dossier Structure (plantlife.org.uk)
  4. 1 2 3 4 5 Daniels RE, McDonnel EJ, Raybould AF. 1998. The current status of Rumex rupestris Le Gall (Polygonaceae) in England and Wales, and threats to its survival and genetic diversity. Watsonia 22: 33 – 39.
  5. Briggs, Helen (7 January 2024). "The woman who spent Christmas in search of a rare plant". bbc.co.uk. BBC News . Retrieved 7 January 2024.
  6. 1 2 3 Bioret F, Daniels R. 2006. Assessment of threats to populations of Rumex Rupestris Le Gall (Shore Dock) in Britain and France. In: Leach SJ, Page CN, Peytoreau Y, Sanford MN. Botanical Links in the Atlantic Arc. BSBI Publications. (PDF) Assessment of threats to populations of Rumex rupestris Le Gall (Shore Dock) in Britain and France (researchgate.net)
  7. Daniels RE, Moy IL. 1998. Species Recovery Programme – Shore Dock (Rumex rupestris Le Gall) 1998 Report. English Nature. 20 pp.
  8. 1 2 Davis R. 1999. Species action plan for plants: shore dock. English Nature, Peterborough. 18 pp.
  9. Wiggington M. 1999. British Red Data Book 1: Vascular plants. 3rd Edition. JNCC Peterborough.
  10. Council Of European Communities. 1992. Council Directive 921431EEC of 2l May 1992 on the Conservation of Natural Habitats and Wild Fauna and Flora. (The Habitats Directive) CEC, Brussels.