Identifying Alder

Alder belongs to the same family as Birch (Betulaceae). It rarely grows to more than 20 metres or lives longer than 150 years. It grows quickly and is short lived – typical of pioneer species. It fixes nitrogen and generally improves the soil.

It is found across most of Europe, into Russia; also the Caucasus, Turkey and Iran. It is typically found in wet areas and alongside streams and rivers, in wet woodland it is sometimes referred to as alder carr. Wood (from coppiced trees) was used for clog making at one time and is said to be good for charcoal making.

Leaf

The leaves are rounded but tapering towards the leaf stalk. Some describe it as being pear-shaped. The margin is toothed, but there are fewer teeth towards the petiole. The apex of the leaf is quite rounded. 6 – 8 pairs of veins, which are almost ‘sunken’ into the surrounding leaf tissue. The leaves tend to remain on the trees until quite late in the year.

Buds, Bark and Stem

Dark grey and fissured bark. The twigs can be sticky (hence the name glutinosa). The image to the left shows the old bark on the left and young on the right.

Flowers and Fruits

Alder is monoecious: it produces both male and female flowers on the same tree. The male flowers or catkins are a dark yellow brown colour, about 2 inches long when open. The female flowers are much smaller in size, cone-shaped and red. When fertilised, these become green fruits, which gradually become woody and eventually release small, reddish brown seeds. The empty cones may remain on the tree until the following spring.

Winter Twigs

Identifying Alder

Leaf

Buds, Bark and Stem

Flowers and Fruits

Winter Twigs

Tree species