Alnus rugosa
Speckled Alder
a perennial woody deciduous member of the Alnus genus in the family Betulaceae.
Taxonomy and growth
- Family
- Betulaceae
- Genus
- Alnus
- Life cycle
- perennial
- Foliage
- deciduous
- Woodiness
- woody
- Growth rate
- vigorous
- Height
- 22 m
- Fertility
- Wind
- Flower type
- monoecious
- Pollinators
- Wind
Uses
Medicinal uses
Historical medicinal uses. These records describe reported uses. They do not establish safety or effectiveness. Ask a qualified health professional before using any plant medicinally.
This section contains historical Plants For A Future notes marked noncommercial.
The speckled alder was quite widely used medicinally by the native North American Indians who used it to treat a variety of complaints[8]. It is little used in modern herbalism. The bark is alterative, astringent, emetic, laxative, ophthalmic, stomachic and tonic[9][11][8]. The bark contains salicin[5], which probably decomposes into salicylic acid (closely related to aspirin) in the human body[4]. This is used as an anodyne and febrifuge[5]. The root bark was mixed with molasses and used in the treatment of toothache[8]. A decoction of the inner bark was used as a wash for sore eyes[8]. The outer bark is astringent and is applied as a poultice to bleeding wounds, it also reduces swellings[5].
- Product or use
- Alterative
- Product or use
- Anodyne
- Product or use
- Astringent
- Product or use
- Cathartic
- Product or use
- Emetic
- Product or use
- Febrifuge
- Product or use
- Odontalgic
- Product or use
- Ophthalmic
- Product or use
- Stomachic
- Product or use
- Tonic
Material uses
This section contains historical Plants For A Future notes marked noncommercial.
This is an excellent pioneer species for re-establishing woodlands on disused farmland, difficult sites etc[5]. 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 tree has an extensive root system and can be planted to control banks from erosion[5]. A dark dye is obtained from the bark[5]. Browns, through red to orange colours can be obtained from the bark[8]. The wood is soft, weighing 29lb per cubic foot[7]. The tree is too small to be of importance for lumber or fuel[6].
- Product or use
- Dye
- Product or use
- Wood
Ecology and functions
- Ecosystem niche
- Canopy
Environment
- Range
- Northern and Eastern N. America - Hudson's Bay to Virginia. Naturalized in C. Europe[10].
- Habitat
- Wet sandy or gravelly soils, usually along streams and rivers, but also in ponds and swamps[6]. It is only found in open sunny areas, being unable to compete in dense shade[6].
- Light
- full sun
- Shade tolerance
- light shade
- Water
- high
- Hardiness
- Zone 2+
- Soil textures
- loamy, clay, heavy clay
- Soil pH
- acid, neutral, alkaline
- Tolerates Nutritionally Poor Soil
- No
- Drought
- intolerant
Propagation
This section contains historical Plants For A Future notes marked noncommercial.
Seed - best sown in a cold frame as soon as it is ripe and only just covered[3]. Spring sown seed should also germinate successfully so long as it is not covered[200, K]. The seed should germinate in the spring as the weather warms up. When large enough to handle, prick the seedlings out into individual pots. If growth is sufficient, it is possible to plant them out into their permanent positions in the summer, otherwise keep them in pots outdoors and plant them out in the spring. If you have sufficient quantity of seed, it can be sown thinly in an outdoor seed bed in the spring[12]. The seedlings can either be planted out into their permanent positions in the autumn/winter, or they can be allowed to grow on in the seed bed for a further season before planting them. Cuttings of mature wood, taken as soon as the leaves fall in autumn, outdoors in sandy soil.
Cultivation
This section contains historical Plants For A Future notes marked noncommercial.
Prefers a heavy soil and a damp situation[1][2]. Grows well in heavy clay soils[2]. Tolerates very infertile sites[3]. A fast-growing but short-lived tree[6]. Closely related to A. incana[2] and considered to be no more than a sub-species (A. incana rugosa) by some botanists[5]. 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[3].
References
F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951-00-00
Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981-00-00
Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5
Weiner. M. A. Earth Medicine, Earth Food. Ballantine Books 1980-00-00 ISBN 0-449-90589-6
Lauriault. J. Identification Guide to the Trees of Canada Fitzhenry and Whiteside, Ontario. 1989-00-00 ISBN 0889025649
Elias. T. The Complete Trees of N. America. Field Guide and Natural History. Van Nostrand Reinhold Co. 1980-00-00 ISBN 0442238622
Britton. N. L. Brown. A. An Illustrated Flora of the Northern United States and Canada Dover Publications. New York. 1970-00-00 ISBN 0-486-22642-5
Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998-00-00 ISBN 0-88192-453-9
Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim 1959-00-00
? Flora Europaea Cambridge University Press 1964-00-00
Usher. G. A Dictionary of Plants Used by Man. Constable 1974-00-00 ISBN 0094579202
Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948-00-00