Sorbus is treated here in the broad sense, including the subgenera Aria and Torminaria. However, these two subgenera are likely to be recognized at generic rank, based on flower and fruit characters, once molecular studies can consistently resolve their placement within the Pyrinae, overcoming current difficulties with interfertility, reticulate relationships, rapid radiation, and small samples[].
The taxonomy of Sorbus is complicated by apomixis, polyploidy, and hybridization among sections and genera, especially in Eurasia. Sorbus hybridizes with several other genera in the tribe Maleae, including Amelanchier (×Amelasorbus Rehder); Crataegus (×Crataegosorbus Makino); Aronia (×Sorbaronia C. K. Schneider); Cotoneaster (×Sorbocotoneaster Pojarkova); Pyrus (×Sorbopyrus C. K. Schneider), and Malus (×Tormimalus Holub [= Sorbus subg. Torminaria × Malus])[].

Common Name: Mountain Ash

General Information

Sorbus aucuparia is a deciduous tree that usually grows from 4 - 15 metres tall, occasionally reaching 20 metres in good sites but remaining a shrub on poorer sires[, , ]. Usually single-stemmed, though sometimes up to 4 main stems are formed[].
The tree is harvested from the wild for local use as a food, medicine and source of materials. It is sometimes cultivated for its edible fruit, is often grown as an ornamental and can be used in shelterbelt plantings.
Widely grown as an ornamental, this species has fruits that are very attractive to birds. The plant is considered to be invasive in N. America, where it has escaped from cultivation by means of bird-sown plants and has become established in many native habitats[].

Known Hazards

Large quantities of the raw fruit can cause vomiting, especially if people are not used to the fruit.
Although no specific information has been seen, the seed, and other parts of the plant, is likely to contain cyanogenic glycosides. When injested, these compounds break down in the digestive tract to release cyanide. Used in small quantities in both traditional and conventional medicine, this exceedingly poisonous compound has been shown to stimulate respiration, improve digestion, and promote a sense of well-being[]. It is also claimed by some to be of benefit in the treatment of cancer - though this claim has been largely refuted.
In larger concentrations, however, cyanide can cause gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma and respiratory failure leading to death[].
The levels of toxin can be detected by the level of bitterness:- sweet almonds, for example, contain only very low levels of it and are safe to eat in quantity, whilst bitter almonds (which are used as a flavouring in foods such as marzipan) contain much higher levels and should only be eaten in very small quantities. Great caution should be employed if the taste is moderately to very bitter[].

Botanical References

, ,

Range

Throughout Europe, east to Turkey and the Caucasus

Habitat

Woods, scrub and mountain rocks, mainly on lighter soil, rare or absent on clays or soft limestones. It is found at higher elevations than any other native tree[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Deciduous Tree
Height	10.00 m
Growth Rate	Medium
Pollinators	Insects
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Sorbus aucuparia is a very cold-hardy tree, tolerating temperatures down to around -40°c when dormant and succeeding in regions with a short growing season[].
Succeeds in most reasonably good soils in an open sunny position[]. Grows well in heavy clay soils. Tolerates some shade[], though it fruits better in a sunny position[]. Prefers a cool moist position and a lighter neutral to slightly acid soil[, , ]. Dislikes shallow soils or drought[, ]. Succeeds on chalk or acid peats[, ]. A very wind firm tree tolerating very exposed and maritime positions[, ]. Tolerates atmospheric pollution[].
Some named varieties have been developed for their improved fruits which are larger and sweeter than the type[].
Plants, and especially young seedlings, are quite fast growing[]. The tree starts fruiting when around 15 years old, but is quite short lived, usually dying before it is 100 years old[].
The fruit is very attractive to birds. 28 species of insects are associated with this tree[].
Responds well to coppicing[].
Plants are susceptible to fireblight[].

Edible Uses

Fruit - raw or cooked[, , , , ]. The fruit is very acid and large quantities of the raw fruit can cause stomach upsets[, ]. It can be used to make delicious, if slightly acidulous, jams and preserves[], the fruit can also be dried and used as a flour mixed with cereals[, ]. The yellow or orange-red to red, globose to subglobose fruit is 8 - 12mm in diameter[], and is produced in quite large bunches making harvest easy[].

The leaves and flowers are used as a tea substitute[, ].

Young leaves are said to be a famine food but they contain a cyanogenic glycoside so you should be very hungry before even thinking of eating them[].

A coffee substitute[]. The report was referring to the fruit, it probably means the roasted seed.

Medicinal

The bark is astringent, it is used in the treatment of diarrhoea and as a vaginal injection for leucorrhoea etc[].

The fruit is antioxidant, antiscorbutic, astringent and diuretic[, , ]. It is normally used as a jam or an infusion to treat diarrhoea, haemorrhoids, kidney stones etc[, ]. An infusion can also be used as a gargle for sore throats and as a wash to treat haemorrhoids and excessive vaginal discharge[].
The seeds contain cyanogenic glycosides which, in reaction with water, produce the extremely toxic prussic acid[]. In small quantities this acts as a stimulant to the respiratory system but in larger doses can cause respiratory failure and death[]. It is therefore best to remove the seeds when using the fruit medicinally or as a food[].

Both the flowers and the fruit are aperient, mildly diuretic, laxative and emmenagogue[, , ]. An infusion is used in the treatment of painful menstruation, constipation and kidney disorders[].

Agroforestry Uses:

Trees are very wind resistant and can be used in shelterbelt plantings[, ].
Mountain ash is a natural pioneer species, often growing in open situations and able to withstand root competition from perennial plants[]. It can be used in reforestation projects and also for establishing a woodland garden[].
The tree has a wide-ranging root syste, and can be grown in areas with high erosion rates such as the European mountain systems, where it helps to increase the stability of slopes and mitigate erosion. It is also useful for deep reinforcement and soil strength enhancement[].

Other Uses

An oil is obtained from the seed[].

A cosmetic face-mask is made from the fruits and is used to combat wrinkled skin[].

A black dye is obtained from the young branches[]. All parts of the plant contain tannin and can be used as a black dye[]. The bark contains 7.26% tannin compounds[].

The reddish wood is fine grained, lustrous, hard, strong and tough but not durable outdoors. It polishes well. A compact and elastic wood, it is highly recommended by wood turners and is also used to make furniture, hoops for barrels etc, and especially for machine parts such as blocks, rollers, and cogs that require great strength[, , , , , ].

Propagation

Seed - best sown as soon as it is ripe in a cold frame[, ]. If you have sufficient seed it can be sown in an outdoor seedbed[, ]. Stored seed germinates better if given 2 weeks warm then 14 - 16 weeks cold stratification[], so sow it as early in the year as possible. Prick out the seedlings into individual pots when they are large enough to handle. Seedlings are very slow to put on top-growth for their first year or two[], but they are busy building up a good root system. It is best to keep them in pots in a cold frame for their first winter and then plant them out into their permanent positions in late spring.