Sorbus aucuparia

Taxobox
name = "Sorbus aucuparia"


image_width = 240px
image_caption = Rowan growing with Mountain Pine on a mountainside in the Italian Alps
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Rosales
familia = Rosaceae
subfamilia = Maloideae
genus = "Sorbus"
subgenus = "Sorbus"
species = "S. aucuparia"
binomial = "Sorbus aucuparia"
binomial_authority = L.

"Sorbus aucuparia" (Rowan or European Rowan), is a species of the genus "Sorbus" (subgenus "Sorbus"), native to most of Europe except for the far south, and northern Asia. In the south of its range in the Mediterranean region it is confined to high altitudes in mountains.Rushforth, K. (1999). "Trees of Britain and Europe". Collins ISBN 0-00-220013-9.] Den Virtuella Floran: [http://linnaeus.nrm.se/flora/di/rosa/sorbu/sorbaucv.jpg"Sorbus aucuparia" map] ]

It has received many alternative names, the most frequently seen being "Mountain Ash"Vedel, H., & Lange, J. (1960). Trees and Bushes in Wood and Hedgerow. Methuen & Co Ltd.] Arkive: [http://www.arkive.org/species/ARK/plants_and_algae/Sorbus_aucuparia/more_info.html Rowan ("Sorbus aucuparia")] ]

It is a small to medium-sized deciduous tree typically growing to 8–10 m tall, more rarely 20 m, and exceptionally to 28 m. [Tree Register of the British Isles] The bark is smooth, silvery grey of young trees, becoming scaly pale grey-brown and occasionally fissured on old trees. The shoots are green and variably hairy at first, becoming grey-brown and hairless; the buds are conspicuous, purple-brown, and often densely hairy. The leaves are pinnate, 10–22 cm long and 612 cm broad, with 9–19 (most often 13–15) leaflets; each leaflet is 3–7 cm long and 15–23 mm broad, with a coarsely serrated margin; they are variably hairy, particularly the petiole and leaf veins on the underside. The hermaphrodite flowers are produced in large terminal corymbs 8–15 cm diameter with up to 250 flowers, the individual flowers 1 cm diameter, with five creamy-white petals, and are insect pollinated. The fruit is a small pome 6–9 mm (rarely up to 14 mm) diameter, green at first, ripening bright red in late summer, and containing up to eight (most commonly two) small seeds. It is diploid, with a chromosome count of 2"n"=34.Trees for Life Species Profile: [http://www.treesforlife.org.uk/tfl.rowan.html Rowan] ] Flora of NW Europe: [http://ip30.eti.uva.nl/BIS/flora.php?selected=beschrijving&menuentry=soorten&id=2736 "Sorbus aucuparia"] ]

Five subspecies are recognised:Flora Europaea: [http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Sorbus&SPECIES_XREF=aucuparia&TAXON_NAME_XREF=&RANK= "Sorbus aucuparia"] ]
*"Sorbus aucuparia" subsp. "aucuparia". Temperate Europe and northwest Asia, south to central Spain, central Italy, and northernmost Greece, and east to the Ob and Irtysh rivers. Tree form; leaves and shoots hairy.
*"Sorbus aucuparia" subsp. "fenenkiana" T.Georgiev & Stoj. Bulgaria (endemic).
*"Sorbus aucuparia" subsp. "glabrata" (Wimm. & Grab.) Cajander. (syn. "S. glabrata" (Wimm. & Grab.) Hedl.). Subarctic regions, from Iceland, northernmost Scotland (Orkney, Shetland), northern Scandinavia, northwest Russia, and also locally at tree line in central Europe in the Alps and Carpathians. Shrubby; leaves and shoots less hairy.
*"Sorbus aucuparia" subsp. "praemorsa" (Guss.) Nyman. High altitudes in the Mediterranean region in France (Corsica) and Italy (Sicily and Calabria).
*"Sorbus aucuparia" subsp. "sibirica" (Hedl.) Krylov (syn. "S. sibirica" Hedl.). Temperate northern Asia, east of the Ob and Irtysh rivers. Tree form; leaves and shoots hairless.

Ecology

Rowan is very tolerant of cold and is often found at high altitude on mountains; in the UK it occurs at up to 1,000 m altitude, higher than any other tree, and in France up to 2,000 m.Mitchell, A. F. (1982). "The Trees of Britain and Northern Europe". Collins ISBN 0-00-219037-0]

It is very tolerant of a wide range of soil conditions, including thin acid soils and cracks in cliffs. It also fairly frequently grows as an epiphyte in clefts or cavities of larger trees such as Scots Pines, though epiphytic specimens rarely have growing conditions adequate for them to reach maturity.

The fruit is an important food resource for many birds, notably Redwings, Fieldfares, Blackbirds, Mistle Thrushes and Waxwings, which in turn disperse the seeds in their droppings. The seeds are eaten by Pine Grosbeaks and other large finches.Snow, D. W. & Perrins, C. M. (1998). "The Birds of the Western Palearctic" Concise Edition. OUP ISBN 0-19-854099-X.]

The foliage and bark is eaten by Red Deer, Roe Deer, and Mountain Hares, and a small number of insect larvae, including leaf-miners in the genus "Stigmella", and the moth "Venusia cambrica". The snail "Helix aspersa" also feeds on the leaves.

Cultivation and uses

Like other rowans, it is widely grown as an ornamental tree. Several cultivars have been selected, including 'Asplenifolia' with very deeply serrated leaves, 'Beissneri' with coppery-orange bark and erect branching, and 'Fructu Luteo' with yellow fruit.

The fruit, called rowan berries in culinary usage, are usually very bitter and inedible fresh, but are used to make jam or jelly, with a distinctive bitter flavour. Rowan jelly is a traditional accompaniment to game and venison. [Davidson, A. (1999). "The Oxford Companion to Food". Oxford University Press ISBN 0-19-211579-0.] The cultivar 'Edulis' has been selected for its less bitter fruit.

In the United Kingdom, where it is often known as the "wiggen tree", the Mountain Ash has traditionally been used as an anti-witching device. [ [http://books.google.co.uk/books?ct=result&id=6-E8AAAAIAAJ&jtp=674 "Witchcraft: The Mountain Ash"] , in "The Every-day Book and Table Book; or, Everlasting Calendar of Popular Amusements, Sports, Pastimes, Ceremonies, Manners, Customs, and Events, Each of the Three Hundred and Sixty-Five Days, in Past and Present Times; Forming a Complete History of the Year, Months, and Seasons, and a Perpetual Key to the Almanac, Including Accounts of the Weather, Rules for Health and Conduct, Remarkable and Important Anecdotes, Facts, and Notices, in Chronology, Antiquities, Topography, Biography, Natural History, Art, Science, and General Literature; Derived from the Most Authentic Sources, and Valuable Original Communication, with Poetical Elucidations, for Daily Use and Diversion. Vol III.", ed. William Hone, (London: 1838) p 674-75.] [ [http://books.google.co.uk/books?id=Ha7dHO3W6L8C&pg=PA72&vq=mountain+ash&source=gbs_search_r&cad=1_1&sig=ACfU3U26q4esJQMAaKSPvaAgE-hlDPt6rA#PPA72,M1 "The Mountain Ash, or Wicken or Wiggen Tree"] , in Lancashire Folk-lore: Illustrative of the Superstitious Beliefs and Practices, Local Customs and Usages of the People of the County Palantine", edited by John Harland and T. T. Wilkinson, (London: 1867) p 72-74.]

References