The Trees at Keele
Common Alder - Alnus glutinosa
Origins : A native species that grows alongside streams, fens, carrs, lakes etc in all parts of the UK.
Leaf : The leaf shape is rounded whereas the other Alders at Keele have more oval-shaped leaves.
Flowers :The male catkins occur in groups of 3 - 5 and are dull purple in the winter but open a dull-yellow colour and 5cm long in the spring. The female catkins, often mistakenly called cones, provide a rich food-source for birds in the winter, especially Redpolls and Siskins.
Fruit : The seeds have cork-like growths which allows them to float on water and thereby move freely along watercourses.
The roots contain nitrogen fixation nodules which make up for the lack of nitrogen in the water-logged soils in which it grows. It is sometimes planted to enrich poor ground and to prevent erosion of river banks.
Uses : The wood is yellow when seasoned and works easily. It was once used to make clogs and mill-wheel cogs.
Its natural habitat of watery places meant that it was also used for sluices, water troughs and piles, while the dry wood makes good charcoal.
- Common around the lakes.