Sälgen

Sälgen, commonly known as the European aspen (Populus tremula), is a deciduous tree in the family Salicaceae. In Swedish usage, sälg refers to this species, and “sälgen” is the definite form.

It typically reaches 15–25 meters tall, with a straight trunk and smooth grayish-brown bark that becomes fissured with age. The leaves are round to ovate, 2–5 cm across, with finely serrated margins. A distinctive feature is the flattened petiole, which makes the leaves flutter vigorously in light wind.

Sälgen is native to much of Europe and western Asia, ranging from southern Scandinavia to the Caucasus and parts of the British Isles. It favors moist, well-drained soils in mixed deciduous forests, riverbanks, clearings, and damp meadows. It is often one of the first trees to establish after disturbance.

It reproduces by wind-dispersed seeds enclosed in cottony fibers in spring and by extensive root suckering, forming clonal groves. The species provides habitat and food for various insects, birds, and fungi and serves as a pioneer species in ecological succession.

Timber from aspen is light and soft, used for pulp, low-grade timber, and crafts; it is also valued ornamentally in parks and streets in its native range. The tree has cultural associations in northern European folklore and is noted for its quivering leaves.

Sälgen is widespread and not generally considered threatened. Local declines may occur due to drainage, land-use change, or competitive pressure from fast-growing species, but overall the species remains common across its range.