Grauerle

Landscape Uses:Pollard, Specimen. Prefers a heavy soil and a damp situation. Grows well in heavy clay soils. Thrives in drier soils than many other members of this genus. Tolerates very infertile sites. This species has a symbiotic relationship with certain soil micro-organisms, these form nodules on the roots of the plants and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Special Features:Attractive foliage, Not North American native, Wetlands plant, Inconspicuous flowers or blooms. The plant is heat tolerant in zones 6 through 1. (Plant Hardiness Zones show how well plants withstand cold winter temperatures. Plant Heat Zones show when plants would start suffering from the heat. The Plant Heat Zone map is based on the number of "heat days" experienced in a given area where the temperature climbs to over 86 degrees F (30°C). At this temperature, many plants begin to suffer physiological damage. Heat Zones range from 1 (no heat days) to 12 (210 or more heat days). For example Heat Zone. 11-1 indicates that the plant is heat tolerant in zones 11 through 1.) For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a standard with a non-suckering single trunk [1-2]. In garden design, as well as the above-ground architecture of a plant, root structure considerations help in choosing plants that work together for their optimal soil requirements including nutrients and water. The root pattern is branching: a heart root, dividing from the crown into several primary roots going down and out [2-1].

The inner bark is technically edible but of very poor quality. It contains high levels of bitter tannins that require extensive processing—boiling in multiple changes of water, drying, and grinding into flour. Even then, the bitterness persists, and the flour has little nutritional value. The bark is available year-round but should only be considered as a survival food, and even then, only if mixed with more nutritious ingredients. The flowers (catkins) are a better resource. Male catkins, which appear from late winter through early summer, can be boiled and eaten. They have a distinctive, somewhat bitter and resinous flavor, but are tolerable compared to other alder parts. The texture is dry, grainy, and fully chewable. Male catkins can also be harvested for their pollen, which can be sifted off and sprinkled back onto the cooked catkins; however, pollen may trigger allergies in sensitive individuals. Female catkins are small and woody, eventually maturing into cone-like structures that are not suitable for food. The sap and other tissues of alder contain tannins and are not suitable for consumption as food.

Pioneer Soil reclamation Tannin Wood This species fixes atmospheric nitrogen and is also tolerant of polluted soils, it can be used for land reclamation, especially on coal tips. This is an excellent pioneer species for re-establishing woodlands on disused farmland, difficult sites etc. Its fast rate of growth means that it quickly provides sheltered conditions to allow more permanent woodland trees to become established. In addition, bacteria on the roots fix atmospheric nitrogen - whilst this enables the tree to grow well in quite poor soils it also makes some of this nitrogen available to other plants growing nearby. Alder trees also have a heavy leaf canopy and when the leaves fall in the autumn they help to build up the humus content of the soil. Alder seedlings do not compete well in shady woodland conditions and so this species gradually dies out as the other trees become established[K]. The bark and the fruits contain up to 20% tannin. Wood - light, soft, fairly elastic, easy to split. Used for clogs, bowls, woodcuts etc. Much valued by cabinet makers.

Heimisch: Alaska, Albania, Alberta, Arizona, Austria, Baltic States, Belarus, British Columbia, Bulgaria, California, Central European Russia, Colorado, Connecticut, Czechia-Slovakia, DK, East European Russia, Europe & Northern Asia (excluding China), Finland, France, Germany, Global, Greece, Hungary, Idaho, Illinois, Indiana, Iowa, Italy, Labrador, Maine, Manitoba, Maryland, Massachusetts, Michigan, Minnesota, Montana, NW. Balkan Pen., Netherlands, Nevada, New Brunswick, New Hampshire, New Jersey, New Mexico, New York, Newfoundland, North America, North Caucasus, North Dakota, North European Russia, Northwest European Russia, Northwest Territories, Norway, Nova Scotia, Nunavut, Ohio, Ontario, Oregon, Pennsylvania, Poland, Prince Edward I., Québec, Rhode I., Romania, Saskatchewan, South European Russia, Sweden, Switzerland, Transcaucasus, Türkiye, Ukraine, Utah, Vermont, Virginia, Washington, West Siberia, West Virginia, Wisconsin, Wyoming, Yukon Eingeführt: AM, Argentina South, Azores, Belgium, Brussels-Capital Region, CZ, Denmark, Flemish Region, Føroyar, Great Britain, Ireland, Northern Ireland, Spain, Walloon Region