Ash (Fraxinus excelsior)
Common ash is found across Europe, from the Arctic Circle to Turkey. It is the third most common tree in Britain. It is currently being affected by Chalara dieback of ash, a disease caused by the Hymenoscyphus fraxineus fungus (previously Chalara fraxinea).
Common name: ash, common ash, European ash
Scientific name: Fraxinus excelsior
UK provenance: native
Interesting fact: ash trees can live to a grand old age of 400 years - even longer if coppiced.
A year in the life of an ash tree
What does ash look like?
Overview: when fully grown, ash trees can reach a height of 35m. Tall and graceful, they often grow together, forming a domed canopy. The bark is pale brown to grey, which fissures as the tree ages. Easily identified in winter by smooth twigs that have distinctively black, velvety leaf buds arranged opposite each other.
Leaves: pinnately compound, typically comprising 3-6 opposite pairs of light green, oval leaflets with long tips, up to 40cm long. There is an additional singular 'terminal' leaflet at the end. The leaves can move in the direction of sunlight, and sometimes the whole crown of the tree may lean in the direction of the sun. Another characteristic of ash leaves is that they fall when they are still green.
Flowers: ash is dioecious, meaning that male and female flowers typically grow on different trees, although a single tree can also have male and female flowers on different branches. Both male and female flowers are purple and appear before the leaves in spring, growing in spiked clusters at the tips of twigs.
Fruits: once the female flowers have been pollinated by wind, they develop into conspicuous winged fruits, or 'keys', in late summer and autumn. They fall from the tree in winter and early spring, and are dispersed by birds and mammals.
Look out for: the black buds and clusters of seeds are key features.
Identified in winter by: ash has distinctive black buds and flattened twigs.
Where to find ash
Ash thrives best in fertile, deep and well drained soil in cool atmospheres. It is native to Europe, Asia Minor and Africa. It often dominates British woodland.
Value to wildlife
Ash trees make the perfect habitat for a number of different species of wildlife. The airy canopy and early leaf fall allow sunlight to reach the woodland floor, providing optimum conditions for wildflowers such as dog violet, wild garlic and dogs mercury, and consequently insects such as the rare and threatened high brown fritillary butterfly.
Bullfinches eat the winged seeds and woodpeckers, owls, redstarts and nuthatches use the trees for nesting. Because trees are so long lived, they support deadwood specialists such as the lesser stag beetle. Often ash is accompanied by a hazel understory, providing the perfect conditions for dormice.
Ash bark is often covered with lichens and mosses. The leaves are an important food plant for the caterpillars of many species of moth, including the coronet, brick, centre-barred sallow and privet hawk-moth.
Mythology and symbolism
The ash tree was thought to have medicinal and mystical properties and the wood was burned to ward off evil spirits. In Norse Viking mythology, ash was referred to as the 'Tree of Life'. Even today it is sometimes known as the 'Venus of the woods'. In Britain we regarded ash as a healing tree.
How we use ash
People have used ash timber for years. It is one of the toughest hardwoods and absorbs shocks without splintering. It is used for making tools and sport handles, including hammers, axes, spades, hockey sticks and oars. An attractive wood, it is also used for furniture. Ash coppices well, which traditionally provided wood for firewood and charcoal.
The main threat to ash trees is Chalara dieback of ash, a disease caused by a fungus called Hymenoscyphus fraxineus (previously Chalara fraxinea). The disease causes trees to lose their leaves and the crown to die back, and usually results in their death.