One of our most beloved trees. Ash is one of the most common trees in the UK,
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 and fissures as the tree
ages. The tree is easily identified in winter by its smooth twigs that have distinctive black,
velvety leaf buds arranged opposite each other.
Look out for: the black buds and clusters of seeds which are key features.
Identified in winter by: its distinctive black buds and flattened twigs.
Leaves
Pinnately compound, typically comprising 3–6 opposite pairs of light green, oval leaflets
with 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
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 and is also found from the Arctic Circle to Turkey. It is the
third most common tree in Britain.
Did you know?
Ash trees are in the olive family (Oleaceae) and produce oil that is chemically similar to
olive oil.
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 wild flowers such as dog violet, wild garlic and dog’s mercury. In turn, these
support a range of insects such as the rare and threatened high brown fritillary butterfly.
Bullfinches eat the seeds and woodpeckers, owls, redstarts and nuthatches use the trees
for nesting. Because the trees are so long lived, they support deadwood specialists such
as the lesser stag beetle. Ash is regularly accompanied by a hazel understorey, providing
the ideal 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