ALDER

Fearnóg / Alnus glutinosa

The leaves of alder are almost round, similar in many respects to those of hazel. Twigs have sticky buds when young, hence the latin name glutinosa. In spring, the tree produces catkins (similar again to those of hazel and birch) which eventually grow into small woody cones 1-1.5cm long, which contain the tree’s seeds.

Alder is a prolific producer of seed, and in favourable conditions it can become quite invasive. Once established, it can grow very quickly, with growth of over 1 metre in a single summer being quite common. The seeds are borne in cone-like structures and are much sought after by birds in winter.

ASH

Fuinseog / Fraxinus excelsior

Ash is one of the most common trees in Ireland. As well as being found in almost every woodland, it is a familiar sight in hedgerows and is frequently the lone tree in the middle of a cultivated field. It can grow to over 35m, and usually has a long, straight trunk.

An easy-to-identify tree that is familiar to most people. The ash keys often persist on the trees through the winter. Even during winter, the bare twigs, with their distinctive black buds, immediately signal an ash tree. In early spring, small blackish or dark purple flowers appear which are soon followed by the composite leaves – leaves in pairs along a single stalk with a single leaf at the end.

BIRCH (Silver)

Beith / Betula pendula

A very distinctive tree, the downy birch grows tall and upright and is graceful but not weeping. Its leaves are wedge-shaped and slightly hairy, hence its name. It produces familiar catkins in spring, which stay on the tree, turning brown and almost dissolving by the autumn. The two-winged fruits are tiny.

Its main wildlife benefit is in its prolific production of tiny seeds in catkins, which attract birds. Because of its rapid growth, it produces much deadwood, which harbours fungi and insects, further benefiting wildlife.

HAWTHORN

Sceach Gheal / Crataegus monogyna

Hawthorn is one of only a few native species to have long, narrow, needle-like thorns which are borne on the twigs all year round. As well as the obvious white flowers and red berries, the hawthorn’s leaves are almost unique: small (around 5cm long) and deeply lobed, they have the appearance of a miniature maple leaf.

Hawthorn grows almost everywhere and can be found from the tops of mountains to the edge of the sea. It is one of the country’s smaller trees, reaching at most 15m, but it can live for several centuries.

OAK

Dair ghallda / Quercus robur

Oak is one of the most identifiable of trees with its distinctively lobed leaves and familiar acorns. The acorns of the common oak have a long stalk, whilst their leaves have almost no stalk. Conversely, the sessile oak (pictured) has acorns with no stalk but leaves with relatively long stalks. The common oak forms a very broad crown and has deeply ridged bark. The sessile oak tends to have a taller, narrower profile.

The Oak is the national tree of Ireland. It can grow up to 40m high and can live for 1,000 years. It is well known for its ability to sustain wildlife – it supports up to 200 species.

ROWAN/MOUNTAIN ASH

Caorthann / Sorbus aucuparia

Rowan is very similar to ash, though smaller in size. It has the same compound leaves with up to seven pairs of opposite leaflets and one terminal leaflet. The leaves are relatively long {5cm) and narrow with toothed edges. Unlike ash, however, rowan has distinctive white flowers which set to form green berries that turn bright red on ripening. Also unlike ash, the bark of rowan is smooth, though it becomes rough and fissured with age.

Often found singly or in small, widely dispersed groups in the mountains, the rowan can reach 25m in height under ideal conditions. It is very widely planted as an ornamental in gardens and public places.

WILLOW

Saileach / Salix spp.

Grey willow is one of the most widespread willows in Ireland. It grows everywhere except on the driest and most well-drained soils. It is particularly abundant in damp places, especially near lakes and bogs. It is a small tree, but can reach up to 15m in height.

The grey willow has familiar, furry catkins resembling rabbits’ tails. These give it the more commonly used name of “pussy willow.” Catkins are clusters of tiny flowers with no petals (they are also found on hazel, alder and birch). The leaves of grey willow are somewhat rounded, two or three times longer than they are wide, and widest in the middle. The leaves are very slightly rough or hairy underneath.