''Malva arborea'' (also known as ''Lavatera arborea'', or, more recently as ''Malva eriocalyx''), the tree mallow, is a species of mallow native to the

coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...

s of western

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

and the Mediterranean region, from

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

and Britain south to

Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...

and

Libya Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to Egypt–Libya bo ...

, and east to

Greece Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders with ...

.Malvaceae Pages
''Lavatera arborea''
/ref>Flora Europaea
''Lavatera arborea''
/ref>''Botanica. The Illustrated AZ of over 10000 garden plants and how to cultivate them'' p. 514. Könemann, 2004.

Description

It is a

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

by annual, biennial or

perennial plant A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

growing to 0.5–2 m (rarely 3 m) tall. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are orbicular, 8–18 cm diameter, palmately lobed with five to nine lobes, and a coarsely serrated margin. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are 3–4 cm diameter, dark pink to purple and grow in fasciculate axillary clusters of two to seven. It grows mainly on exposed coastal locations, often on small

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

s, only rarely any distance inland.Nico Vermeulen: ''The Complete Encyclopedia of Container Plants'' p. 158. Rebo International, Netherlands, 1998. Blamey, M. & Grey-Wilson, C. (1989). ''Flora of Britain and Northern Europe''. Huxley, A., ed. (1992). ''New RHS Dictionary of Gardening''. Macmillan .

Taxonomy

It was first described in 1753 by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

as ''Lavatera arborea'', but was transferred to the genus, ''

Malva ''Malva'' is a genus of herbaceous annual, biennial, and perennial plants in the family Malvaceae. It is one of several closely related genera in the family to bear the common English name mallow. The genus is widespread throughout the temper ...

'', in 1836 by Philip Barker-Webb and Sabin Berthelot. Although long considered a species of ''

Lavatera ''Malva'' is a genus of herbaceous annual, biennial, and perennial plants in the family Malvaceae. It is one of several closely related genera in the family to bear the common English name mallow. The genus is widespread throughout the tempe ...

'', genetic and morphological analysis by Martin Forbes Ray, reported in 1998, suggested it was better placed in the genus ''

'', in which it was named ''Malva dendromorpha'' M.F.Ray. However the earlier name ''Malva arborea'' (L.) Webb & Berthel. was validly published and has priority over ''Malva dendromorpha''.

Habitat

''Malva arborea'' tolerates sea water to varying degrees, at up to 100% sea water in its natural habitat, excreting salt through glands on its leaves.Veitch, C. R., and Michael Norman Clout (editors). (2002.
''Turning the Tide: The Eradication of Invasive Species'': Proceedings of the International Conference on Eradication of Island Invasives.
The World Conservation Union (IUCN): Gland, Switzerland and Cambridge, UK, pages 254-259. . Retrieved on 2007-09-28.Okusanya, O. T., and T. Fawole. (March 1985.
The Possible Role of Phosphate in the Salinity Tolerance of Lavatera Arborea.
The Journal of Ecology, Vol. 73, No. 1, pp. 317-322, , via JSTOR. Retrieved on 2007-09-28. This salt tolerance can be a competitive advantage over inland plant species in coastal areas. Its level of

salinity Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal ...

tolerance is thought to be improved by soil with higher

phosphate In chemistry, a phosphate is an anion, salt, functional group or ester derived from a phosphoric acid. It most commonly means orthophosphate, a derivative of orthophosphoric acid . The phosphate or orthophosphate ion is derived from phospho ...

content, making

guano Guano (Spanish from qu, wanu) is the accumulated excrement of seabirds or bats. As a manure, guano is a highly effective fertilizer due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. G ...

enrichment particularly beneficial.

Uses

The leaves of the species are used in herbal medicine to treat sprains, by steeping them in hot water and applying the poultice to the affected area. It is theorised that

lighthouse A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways. Lighthouses mar ...

keepers may have spread the plant to some British islands for use as a poultice and to treat burns, an occupational hazard. Thought to have been used as an alternative to toilet paper. The seeds are edible and are known in French as "petit pains", or "little breads". Tree mallow was considered a nutritive animal food in Britain in the 19th century, and is still sometimes used as animal

fodder Fodder (), also called provender (), is any agriculture, agricultural foodstuff used specifically to feed domesticated livestock, such as cattle, domestic rabbit, rabbits, sheep, horses, chickens and pigs. "Fodder" refers particularly to food g ...

in Europe. For human consumption, some sources describe the leaves of tree mallow as edible, although not as palatable as common mallow, unless cut very thinly, because of the very velours-like hairy mouth-feel. ''Malva arborea'' has long been cultivated in British gardens, as described in the 1835 self-published book ''British Phaenogamous Botany'', which used the then-common name ''Sea Tree-mallow'': "This species is frequently met with in gardens, where, if it is allowed to scatter its seeds, it will spring up for many successive years, and often attain a large size. The young plants will, as Sir J. E. Smith observes, now and then survive one or more mild Winters; but having once blossomed it perishes."Baxter, William. (1835)
''British Phaenogamous Botany, Or, Figures and Descriptions of the Genera of British Flowering Plants'' Vol. II.
(Self-published): Oxford, pages 112-113. Retrieved on 2007-09-28. While sometimes detrimental to seabird habitat, management of tree mallow (both planting and thinning) has been successfully employed to shelter nesting sites of the threatened

roseate tern The roseate tern (''Sterna dougallii'') is a species of tern in the family Laridae. The genus name ''Sterna'' is derived from Old English "stearn", "tern", and the specific ''dougallii'' refers to Scottish physician and collector Dr Peter McDoug ...

, which requires more coverage than common terns to impede predation.

Invasive spread

Tree mallow seeds may be transported between separated coastal areas by the floating fruit, and seabirds are considered a likely means of spread. The seeds are encased in an impermeable outer case, and can remain viable for years, even after extended immersion in saltwater. The tree mallow's recent increased range among Scottish islands has raised concerns that it is displacing native vegetation, and is reducing

Atlantic puffin The Atlantic puffin ('), also known as the common puffin, is a species of seabird in the auk family. It is the only puffin native to the Atlantic Ocean; two related species, the tufted puffin and the horned puffin is found in the northeastern ...

(''Fratercula arctica'') populations in affected areas. The plant forms dense stands along the island coasts that inhibit breeding, and causes the puffins to abandon their burrows.Invasion of Scottish seabird islands by tree mallow.
(Website.) Centre for Ecology and Hydrology, UK Natural Environment Research Council. Retrieved on 2007-09-28. Its spread among Australian islands in recent decades is thought to be reducing biodiversity, soil retention, and seabird habitat. According to one study, "Crested and Caspian Terns that nest in the open are closed out by the canopy, and Little Penguins (''Eudyptula minor'') and Bridled Terns (''Sterna anaethetus'') are excluded by the lack of undergrowth". In New Zealand it has established on several seabird-dominated islands where it is considered to be a serious ecological weed and for which there are active eradication programmes, such as on North Brother Island in Cook Strait.

References

External links

{{Taxonbar, from1=Q12210226, from2=Q811549

arborea Arborea is a town and ''comune'' in the province of Oristano, Sardinia, Italy, whose economy is largely based on agriculture and cattle breeding with production of vegetables, rice, fruit and milk (notably the local milk product Arborea). Histo ...

Flora of Europe Flora of North Africa Plants described in 1753 Taxa named by Carl Linnaeus Garden plants of Europe