Plantae > Tracheophyta > Magnoliopsida > Fagales > Betulaceae > Alnus > Alnus glutinosa

Alnus glutinosa (European alder)

Synonyms: Alnus glutinosa var. vulgaris; Alnus vulgaris; Betula alnus subsp. glutinosa; Betula alnus var. glutinosa; Betula glutinosa

Wikipedia Abstract

Alnus glutinosa, the common alder, black alder, European alder or just alder, is a species of tree in the family Betulaceae, native to most of Europe, southwest Asia and northern Africa. It thrives in wet locations where its association with the bacterium Frankia alni enables it to grow in poor quality soils. It is a medium size, short-lived tree growing to a height of up to 30 metres (100 ft). It has short-stalked rounded leaves and separate male and female flower in the form of catkins. The small, rounded fruits are cone-like and the seeds are dispersed by wind and water.
View Wikipedia Record: Alnus glutinosa


Invasive Species

Alnus glutinosa is a member of the birch family (Betulaceae) and is native to Eurasia and the northern part of Africa. Members of the Alnus genus are commonly known as alders; A. glutinosa is known as black alder. It can grow up to 50 feet high. It is often cultivated for erosion control, to improve soil and as an ornamental. A. glutinosa is fast growing and can grow in a wide range of soils; this trait increases its invasiveness in susceptible environments. Association with species of the genus Frankia enable A. glutinosa to fix nitrogen (Frankia is a genus of nitrogen fixing filamentous bacteria that live in symbiosis with actinorhizal plants and form root nodules, similar to Rhizobia). A. glutinosa invades damp ecosystems near water sources, wetalnds and riparian zones.
View ISSG Record: Alnus glutinosa


Air Quality Improvement [1]  Low
Allergen Potential [1]  High
Carbon Capture [1]  Low
Screening - Summer [2]  Moderate
Screening - Winter [2]  Porous
Shade Percentage [1]  82 %
Temperature Reduction [1]  Medium-Low
Wind Reduction [1]  Medium-Low
Bloom Period [2]  Mid Spring
Drought Tolerance [2]  Medium
Fire Tolerance [2]  Low
Flower Type [3]  Monoecious
Frost Free Days [2]  4 months 10 days
Fruit/Seed Abundance [2]  Low
Fruit/Seed Begin [2]  Summer
Fruit/Seed End [2]  Fall
Growth Form [2]  Multiple Stem
Growth Period [2]  Spring, Summer
Growth Rate [2]  Rapid
Janka Hardness [4]  650 lbf (295 kgf) Soft
Leaf Type [3]  Deciduous
Lifespan [5]  Perennial
Pollinators [3]  Wind
Propagation [2]  Bare Root, Container, Cutting, Seed
Root Depth [2]  16 inches (41 cm)
Seed Spread Rate [2]  Slow
Seed Vigor [2]  Low
Seeds Per [2]  325000 / lb (716502 / kg)
Shape/Orientation [2]  Erect
Specific Gravity [7]  0.41
Structure [3]  Tree
Usage [3]  Tolerant of clipping and maritime exposure, the alder can be grown in a windbreak or a hedge; The trees are very quick to establish; 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; Because they tolerate very poor soils and also produce nitrogen nodules on their roots, alders are suitable for use in land reclamation schemes. The plants can be used as a source of biomass; According to the phytomass files, annual productivity is estimated at 6 to 9 tonnes per hectare. The tree has yielded 11.8 tonnes per hectare per annum on pulverized fuel ash and annual productivity has been estimated at 8.66 tonnes per hectare, with 5.87 tonnes in wood, bark, and branches, 2.79 tonnes in foliage; Alder has been recommended for consideration for firewood plantations in Tropical highlands where unseasonable cold might destroy the red alder; The powdered bark has been used as an ingredient of toothpastes; Sticks of the bark have been chewed as tooth cleaners; An ink and a tawny-red dye are obtained from the bark; A green dye is obtained from the catkins; A pinkish-fawn dye is obtained from the fresh green wood; A yellow dye is obtained from the bark and young shoots; A cinnamon dye is obtained from the shoots if they are harvested in March; If they are dried and powdered then the colour will be a tawny shade; The bark and the fruits contain up to 20% tannin; The leaves are also a good source of tannin; The leaves are clammy and, if spread in a room, are said to catch fleas and flies on their glutinous surface; Wood - very durable in water, elastic, soft, fairly light, easily worked, easily split. It is often used for situations where it has to remain underwater and is also used for furniture, pencils, bowls, woodcuts, clogs etc. It is much valued by cabinet makers; The wood also makes a good charcoal;
Vegetative Spread Rate [2]  None
Flower Color [2]  Purple
Foliage Color [2]  Green
Fruit Color [2]  Brown
Fruit Conspicuous [2]  Yes
Height [3]  82 feet (25 m)
Width [3]  33 feet (10 m)
Hardiness Zone Minimum [1]  USDA Zone: 3 Low Temperature: -40 F° (-40 C°) → -30 F° (-34.4 C°)
Hardiness Zone Maximum [1]  USDA Zone: 7 Low Temperature: 0 F° (-17.8 C°) → 10 F° (-12.2 C°)
Light Preference [6]  Mixed Sun/Shade
Soil Acidity [6]  Moderate Acid
Soil Fertility [6]  Intermediate
Soil Moisture [6]  Damp
Water Use [1]  High to Moderate
View Plants For A Future Record : Alnus glutinosa

Protected Areas




Mutual (symbiont) 
Cortinarius violaceus (Violet Webcap)[9]
Lactarius lacunarum[9]
Paxillus rubicundulus[9]
Russula decolorans (Copper Brittlegill)[9]



Europe to Kazakhstan, introduced elsewere; Europe to W. Siberia and Turkey, introduced elsewere;

External References

USDA Plant Profile



Attributes / relations provided by
1i-Tree Species v. 4.0, developed by the USDA Forest Service's Northern Research Station and SUNY-ESF using the Horticopia, Inc. plant database.
2USDA Plants Database, U. S. Department of Agriculture
3Plants For A Future licensed under a Creative Commons License
4Wood Janka Hardness Scale/Chart J W Morlan's Unique Wood Gifts
5PLANTATT - Attributes of British and Irish Plants: Status, Size, Life History, Geography and Habitats, M. O. Hill, C. D. Preston & D. B. Roy, Biological Records Centre, NERC Centre for Ecology and Hydrology (2004)
6ECOFACT 2a Technical Annex - Ellenberg’s indicator values for British Plants, M O Hill, J O Mountford, D B Roy & R G H Bunce (1999)
7Forest Inventory and Analysis DB version 5.1, May 4, 2013, U.S. Forest Service
8Biological Records Centre Database of Insects and their Food Plants
9Ecology of Commanster
10HOSTS - a Database of the World's Lepidopteran Hostplants Gaden S. Robinson, Phillip R. Ackery, Ian J. Kitching, George W. Beccaloni AND Luis M. Hernández
11Food eaten by the free-living European bison in Białowieża Forest, Zofia GĘBCZYŃSKA, Marek GĘBCZYŃSKI and Ewa MARTYNOWICZ, Acta Theriologica 36 (3-4), 307-313, 1991.
12Jorrit H. Poelen, James D. Simons and Chris J. Mungall. (2014). Global Biotic Interactions: An open infrastructure to share and analyze species-interaction datasets. Ecological Informatics.
13Ben-Dov, Y., Miller, D.R. & Gibson, G.A.P. ScaleNet 4 November 2009
14New Zealand Institute for Plant & Food Research Plant-SyNZ™ database
Protected Areas provided by Ramsar Sites Information Service
Natura 2000, UK data: © Crown copyright and database right [2010] All rights reserved. Ordnance Survey Licence number 100017955
Biological Inventories of the World's Protected Areas in cooperation between the Information Center for the Environment at the University of California, Davis and numerous collaborators.
GBIF Global Biodiversity Information Facility
Abstract provided by DBpedia licensed under a Creative Commons License