Fraxinus excelsior

Source: Wikipedia, the free encyclopedia.

European ash
Foliage and immature fruit

Near Threatened  (IUCN 3.1)[1]
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Lamiales
Family: Oleaceae
Genus: Fraxinus
Species:
F. excelsior
Binomial name
Fraxinus excelsior
Distribution map

Fraxinus excelsior, known as the ash, or European ash or common ash to distinguish it from other types of

Trondheimsfjord region of Norway.[3][4] The species is widely cultivated and reportedly naturalised in New Zealand and in scattered locales in the United States and Canada.[5][6][7][8]

Description

Male flowers
Seeds of Fraxinus excelsior, popularly known as "keys" or "helicopter seeds", are a type of fruit known as a samara

It is a large

serrated margins, elliptic to narrowly elliptic, 3–12 cm (1.2–4.7 in) long and 0.8–3 cm (0.31–1.18 in) broad and sessile on the leaf rachis.[2] There are no stipules.[2] These features distinguish ash from mountain ash (Sorbus aucuparia) in which the leaves are alternate with paired stipules. The leaves are often among the last to open in spring, and the first to fall in autumn if an early frost strikes; they often fall dull green or develop a bright yellow autumn colour. The flowers are borne in short panicles, open before the leaves, and have no perianth. The female flowers are somewhat longer than the male flowers, dark purple, without petals, and are wind-pollinated. Both male and female flowers can occur on the same tree, but it is more common to find all male and all female trees. A tree that is all male one year can produce female flowers the next, and similarly a female tree can become male.[citation needed] The fruit is a samara 2.5–4.5 cm (0.98–1.77 in) long and 5–8 mm (0.20–0.31 in) broad, often hanging in bunches through the winter;[9] they are often called 'ash keys'.[3][10][11] If the fruit is gathered and planted when it is still green and not fully ripe, it will germinate straight away, however once the fruit is brown and fully ripe, it will not germinate until 18 months after sowing (i.e. not until two winters have passed).[12]

European ash rarely exceeds 250 years of age. However, there are numerous specimens estimated between 200 and 250 years old and there are a few over 250. The largest is in Clapton Court, England and is 9 m (29.5 ft) in girth. There are several examples over 4.5 metres (14.8 ft) in Derbyshire alone.

Distribution

Fraxinus excelsior is native to

Trondheimsfjord region of Norway.[3][4] The species is widely cultivated and reportedly naturalized in New Zealand and in scattered locales in the United States and Canada including Nova Scotia, New Brunswick, Quebec, Massachusetts, Connecticut, New York, New Jersey, Maryland, Ontario, Ohio, Kentucky and British Columbia.[citation needed
]

It is native throughout Britain and Ireland, particularly on limestone, as in northern Scotland, where the most northerly native ashwood in Britain occurs on limestone at Rassal Ashwood.[13] It is widely planted elsewhere.[14]

Ecology

Ash tree (~20m tall) in Wales at 185 m asl in July (l) and March (r), showing branch structure

Ash occurs on a wide range of soil types, but is particularly associated with basic soils on calcareous substrates. The most northerly ashwood in Britain is on limestone at Rassal, Wester Ross, latitude 57.4278 N.[15] Ash prefers moister soil types and is commonly limited by temperature and so not found at the higher colder altitudes in much of Europe, though in Iran, it may reach 2000 m asl. As a young seedling, it is shade tolerant, but older trees are light-demanding. It is an early-succession species and may well outcompete beech and oak, which are later-succession species.[16]

F. excelsior mycorrhizae are of the internal arbuscular mycorrhizal type, in which the fungus grows within the tissues of the root and forms branched, tree-like structures within the cells of the root cortex. Unlike other Fraxinus species, F. excelsior does not form ectomycorrhizae.[2]

The

lilac, is Gracillaria syringella. The usually gregarious larvae form an epidermal gallery (i.e. feed within the leaf) which leads to a brown blotch with black frass. Later, two successive cones are formed by folding the tip of a leaf downwards.[20]

In Britain, 14

galls have been recorded on ash. The British Plant Gall Society defines a gall as "... an abnormal growth produced by a plant under the influence of another organism".[21]

Ash dieback

Ash dieback is caused by the

Chalara fraxinea
. Research into the genetics of the resistance of ash (Fraxinus excelsior) has shown that resistance does occur in European populations, but at least for the samples tested, it is neither common nor strong.
[22][23][24][25] Due to the importance of F. excelsior as a host, Jönsson and Thor 2012 find that rare/threatened lichens face an unusually high (0.38) coextinction risk probability vis-a-vis the host tree in the wooded meadows of Gotland, Sweden.[26]

Genome

The genome of Fraxinus excelsior is being sequenced by two groups of scientists in the United Kingdom. A group at

The Genome Analysis Centre led by Allan Downie are sequencing "Tree 35" from Denmark, discovered by Erik Kjær, which has survived 8 years of ash dieback.[28]

Uses

Veneer of common ash wood
Replica of the body frame from the Volvo ÖV 4 car, made primarily from ash wood

The resilience and rapid growth made it an important resource for smallholders and farmers. It was probably the most versatile wood in the countryside with wide-ranging uses. Until

tennis rackets, and snooker cue sticks,[31] and it was extensively used in the construction of early aircraft. Ash was commonly used green for making chair frames which would be seated with another timber or with woven rush (e.g. those made by Philip Clissett, see also The English Regional Chair[32]). The parts were turned on a pole lathe or shaped with a drawknife
. The practice essentially died out in the early 20th century, but has seen a revival in recent years.

Ash is an important constituent of

vise to form the handle of the walking stick. The light colour and attractive grain of ash wood make it popular in modern furniture such as chairs, dining tables, doors, and other architectural features and wood flooring
.

Ash is the only wood used for the manufacture of hurleys, referred to as hurls in parts of Leinster and known as a camán in Irish, the timber sticks used in the game of hurling in Ireland. Hurleys are manufactured from the butt log (bottom 1.5-m of the stem) and from trees ideally of a diameter at breast height around 25–30 cm. Only fast-grown, straight, and knot-free ash can be used for this purpose. Due to the lack of available ash in Ireland, over 75% of the timber needed to produce the 350,000 hurleys required for the game annually must be imported, mostly from Eastern European countries.[33] The importance of ash timber to the game of hurling is reflected in the fact that the game is referred to all over Ireland as "The Clash of the Ash".

Ash is valuable as firewood because it burns well even when 'green' (freshly cut).[34] Ash bark and leaves are used in modern herbal medicine for its astringent and laxative properties.[35]

Mythology

In the 13th-century Edda and other writing relating to Norse mythology, the vast ash tree Yggdrasil ("the steed (gallows) of Odin"), watered by three magical springs, serves as axis mundi, sustaining the nine worlds of the cosmos in its roots and branches.[36]

Folklore

On the Isle of Bute in Scotland, lovers reportedly used to eat leaves of an ash tree known as the "Dreamin' Tree" that grew near the church of St Blane, and the pleasant dreams they then experienced revealed their actual spouses and intended fates.[37]

Cultivars

Ash saplings from a mast year

Its many cultivars include;

  • Fraxinus excelsior 'Aurea', the traditional, slow-growing golden ash ─ not to be confused with 'Jaspidea'
  • Fraxinus excelsior 'Aurea Pendula' (weeping golden ash)
  • Fraxinus excelsior 'Autumn Blaze'
  • Fraxinus excelsior 'Autumn Purple'
  • Fraxinus excelsior 'Crispa'
  • Fraxinus excelsior 'Diversifolia' (one-leaved ash)
  • Fraxinus excelsior 'Erosa'
  • Fraxinus excelsior 'Jaspidea' a modern, vigorous golden ash
  • Fraxinus excelsior 'Monophylla'
  • Fraxinus excelsior 'Nana'
  • Fraxinus excelsior 'Pendula' (weeping ash), one of the best-known cultivars, widely planted during the Victorian era, grows vigorously forming an attractive small to medium-sized tree with mounds of weeping branches
  • Fraxinus excelsior 'Skyline'

Gallery

  • Two ash trees fused together
    Two ash trees fused together
  • Tree 46 m tall, Château des princes de Croÿ, Le Roeulx, Belgium
    Tree 46 m tall, Château des princes de Croÿ, Le Roeulx, Belgium
  • Old tree, Belgium
    Old tree, Belgium
  • Leaf and shoot, showing black bud
    Leaf and shoot, showing black bud
  • Weeping ash Fraxinus excelsior 'Pendula', Knightshayes Court, England
    Weeping ash Fraxinus excelsior 'Pendula', Knightshayes Court, England
  • Buds
    Buds
  • Bark
    Bark

References

  1. . Retrieved 12 November 2021.
  2. ^ .
  3. ^ .
  4. ^ a b Den virtuella floran: Fraxinus excelsior distribution
  5. ^ "Fraxinus excelsior L." Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 13 July 2023.
  6. ^ Kew World Checklist of Selected Plant Families, Fraxinus excelsior
  7. ^ Biota of North America Program, Fraxinus excelsior
  8. ^ Altervista Flora of the United States and Canada, Fraxinus excelsior
  9. .
  10. ^ .
  11. ^ "Online atlas of the British and Irish Flora, Fraxinus excelsior (Ash)". Biological Records Centre and Botanical Society of Britain and Ireland. Archived from the original on 1 December 2021.
  12. ^ "Wood Pasture: Rassal Ashwood National Nature Reserve". Scottish Natural Heritage. Archived from the original on 6 September 2013.
  13. .
  14. .
  15. ^ Alan Stubbs. "Invertebrates associated with Ash" (PDF). Archived from the original (PDF) on 3 September 2013. Retrieved 28 February 2015.
  16. ^ "Centre-barred Sallow Atethmia centrago". UKmoths. Retrieved 28 July 2017.
  17. ^ "15.014 Gracillaria syringella (Fabricius, 1794)". British leafminers. Retrieved 28 July 2017.
  18. .
  19. .
  20. .
  21. .
  22. ^ Pliūra A, Lygis V, Suchockas V, Bartkevičius E (2011). "Performance of twenty four European Fraxinus excelsior populations in three Lithuanian progeny trials with a special emphasis on resistance to Chlara fraxinea". Baltic Forestry. 17 (1): 17–34. Archived from the original on 2 April 2015.
  23. S2CID 218618105
    .
  24. ^ "Welcome to Ash tree genomes – Ash Tree Genomes". ashgenome.org.
  25. ^ Heap, Tom (16 June 2013). "Ash genome reveals fungus resistance". BBC News.
  26. .
  27. ^ "Ash". Niche Timbers. Retrieved 19 August 2009.
  28. ^ Petrică Tudor M, Ingrid Agnes M, Szilard B. 2011. Study of Physical Characteristics, Mechanical and Technological Properties of Wood Species from the Fraxinus Genus Encountered in Romania Compared to Other Main Forestry Species. Natural Resources and Sustainable Development [1].
  29. .
  30. ^ John Whiriskey; Paul McCarthy, eds. (May 2006). Ash For Hurleys (PDF) (Report). Fact Sheet No. 35. Teagasc – The Agriculture and Food Development Authority. Archived from the original (PDF) on 22 November 2007.
  31. ^ "The burning properties of wood" (PDF). The Scout Association. 1999. Archived from the original (PDF) on 23 December 2012. Retrieved 1 November 2010.
  32. EUFORGEN
    .
  33. .
  34. ^ Downie, R. Angus (1934). Bute and the Cumbraes Glasgow & London: Blackwood & Son Ltd. p. 83

External links