The more than 30 different species of alder belong to the birch family (Betulaceae) and is native to many areas of the northern hemisphere. Three principle types are common in central Europe: the black alder (also called red alder), the white alder (also known as grey alder) and the green alder (also known as mountain alder). The black alder is the only type that is relevant for the wood industry.
Black alders reach a height of approximately 30m and grow very rapidly in the first few years. They have, relatively speaking, a short life span, reaching an age of approx. 100 to 120 years. White alders can grow to 10 to 15 metres high, and generally grow no older than 50 years. Green alder grow generally as small trees or shrubs (up to 5m).
Alder, most notably the black alder, often occur on the banks of watercourses and moist areas. They can be found throughout Europe with the exception of southern Spain and large parts of Scandinavia. It is particularly widespread in the Baltic States, in Poland, in the Spreewald and the foothills of the Alps in Bavaria.
The sapwood and heartwood of the alder are difficult to differentiate. The wood is reddish-white or reddish-yellow to reddish coloured and darkens when exposed to light. The annual growth rings are not particularly clear, however on closer inspection the large pore structure of the springwood can be seen.
The properties of wood from the black alder and white alder are more or less identical. The wood of the black alder is slightly heavier and firmer, but on the whole they can be regarded as equivalent.
Alder wood is generally light and soft. Its structure is even with straight fibres. It is not very susceptible to shrinkage and remains stable after drying.
The wood is not very firm and less elastic, its stability and elasticity is comparable to that of lime wood.
Alder wood is not naturally durable when exposed to the elements, however when used underwater it remains stable.
Alder wood can be dried easily. It is not very susceptible to cracking. It is easy to work manually or by machine, well suited to turning and carving. Surface finishing is unproblematic, in particular it is easy to stain and is often used as an alternative to expensive high-grade woods.
Alder is available as round or sawn timber as well as veneer.
- Model building
- Picture frames
- Musical instruments
- Closed veneer
- Alternative to high-grade woods (when stained)
- Carving, turning and sculpting