Alnus alnobetula - Green alder

Alnus alnobetula, also known as the green alder, is a multi -stamped deciduous shrub from the Betulaceae family. This type of plant is native to the mountain regions of Europe, Asia and North America and plays an important role in high -assembly and subalpine ecosystems. Alnus alnobetula is known for her ability to house nitrogen -fixing bacteria, which gives it a special ecological meaning.

Morphology

Alnus alnobetula is a densely branched shrub, which usually reaches a height of 3 to 5 meters, but can also become up to 7 meters high in favorable conditions. The bark is smooth and gray -brown, with numerous lenticals that give the plant a characteristic appearance.

The leaves are elliptical to egg -shaped, about 4 to 10 centimeters long, with a serrated edge and a dark green, glossy surface. The underside of the leaves is lighter and slightly hairy. These leaves remain green until late in autumn, which gives the plant their name.

The flowers of Alnus alnobetula appear in early spring before the leaves sprout. The plant is one -house, which means that male and female flowers are separated, but occur on the same plant. The male kittens are hanging, about 4 to 7 centimeters long and form in autumn, while the female inflorescences are smaller and consist of short, upright kitten that develop small, woody cones after fertilization. These cones contain the seeds and often stay on the plant during winter.

Ecology and distribution

Alnus alnobetula is widespread in the mountain regions of Central and Southern Europe, in the Caucasus, in Siberia and in parts of North America. The plant prefers cool, moist locations and often grows along mountain streams, in bogs and on mountain slopes. It is a typical pioneering shrub on bare areas such as avalanche railways, former glacier envelouts and surfaces exposed by clearing.

The green alder has a special ecological niche because it lives in symbiosis with nitrogen -fixing bacteria (Frankia) that occur in the root nodules of the plant. These bacteria bind atmospheric nitrogen and make it available for the plant and the soil, which improves soil fertility and facilitates the establishment of other plant species. Because of this ability, Alnus alnobetula plays a key role in the succession of vegetation in alpine and subalpine areas.

Adjustments and habitat

The green alder is excellently adapted to rough environmental conditions. They firmly anchor their deep roots in the ground and enable them to obtain nutrients and water from deeper layers of the soil. The ability to grow in cool, damp soils makes them particularly suitable for settlement of mountain slopes and other unstable locations. Her ability to grow vegetative by foothills enables her to form dense stocks that stabilize the soil and protect against erosion.

The green alder often forms thicknesses that offer other plant species and animals. In alpine regions it is often one of the few wood plants that thrive under the extreme conditions. These thicknesses offer habitat for a variety of animal species, including birds and small mammals, and contribute to the biodiversity of the region.

Protection and meaning

Alnus alnobetula is not endangered in its natural distribution area and is considered a adaptable and widespread species. In some regions, however, the greener is considered problematic due to its rapid spread, since it can overgrow pasture and thus changes vegetation. In other areas, it is estimated, especially because of its role in stabilizing mountain slopes and restoring disturbed areas.

The plant also has a meaning in traditional use. In the past, the leaves and branches of the green alder were used as a litter and feed for cattle. The wood, although it is small and often curved, was used in the production of tool stems and small craftsmanship.