Alnus incana pendula- Grey Alder

Alnus incana 'Pendula' is a beautiful weeping form of the white alder, a deciduous native tree that is very robust. This variety is smaller than the species. It develops a very straight, very light grey trunk, which gives rise to several branches that spread quite widely in graceful arcs, with secondary branches and branches that hang rather stiffly; given space, it makes a truly graceful landscape tree. It is noticeable from the end of winter, with its slightly tousled branches, adorned with purple and pendant catkins.

Alnus incana 'Pendula' was discovered in Poland at the end of the 19th century. It is a deciduous tree of the Betulaceae family, just like birch trees. The species, also known as mountain alder or grey alder, is native to temperate regions of the Northern Hemisphere and is hardy down to -36ºC. Thanks to its flexibility and ability to produce suckers, it is one of the few trees capable of withstanding avalanches. It is a pioneer, fast-growing species, capable of forming dense stands in poor, limestone soils. Its deep and spreading root system allows it to withstand wind and anchor itself firmly even in very unstable, sloping soil. The white alder thrives in limestone soils and adapts well to both wet and moderately dry soils in summer.

The 'Pendula' white alder reaches a height of 6 to 8 metres and a spread of 3 to 5 metres. Its growth rate is moderate and depends on the growing conditions. This variety develops a trunk that gives rise to arched main branches and a canopy with all parts trailing. The entire canopy resembles large green curtains. The trunk and young branches are light grey. The deciduous foliage appears in spring and falls in autumn. It is airy, light green, composed of spaced, oval leaves with coarse-toothed edges. The branches and the undersides of the leaves are covered in a light fuzz. The leaves are a fairly dark green and slightly glossy. They fall in autumn. The decorative flowering occurs in February. The tree bears inconspicuous female catkins, measuring about 5 cm long, and more decorative, violet male catkins, 7 cm long, with a powdery yellow pollen. After pollination by insects, the female flowers transform into fruits. These are grey-brown cones, visible from September onwards, remaining attached to the branches throughout winter. They release narrow-winged nuts that are dispersed by the wind and provide an important food source for certain birds.

Alnus incana 'Pendula' should be planted in an area sufficiently large enough for it to reach its full size and in a well-exposed location to enjoy its natural elegance. Plant violets or periwinkles at its base. Surround it with low-growing shrubs that appreciate limestone, such as St. John's wort, for example.

White alder is often planted to populate poor and unstable mountain soils, as well as on slag heaps. Its root system forms nodules containing bacteria that fix nitrogen from the air, returning this richness to the soil. It is also found in windbreak hedges in the plains.

Alnus incana comes from the Latin word incanus, which means "covered with grey-white hairs," referring to the hairy undersides of young leaves. The leaf is used as a diuretic and vermifuge. The bark is astringent and tonic.