SafePlants

Alnus incana (Grey Alder or Speckled Alder)

Alnus incana, commonly known as grey alder or speckled alder, is a versatile tree or shrub found throughout the cooler regions of the Northern Hemisphere. Its adaptability and fast growth make it a valuable species for various ecological and practical applications.

Considerations for Pets

• The text mentions that Alnus incana is part of the birch family (Betulaceae), and the bark can be used in tanning and dyeing. While the text does not provide specifics about toxicity, these properties might warrant caution if pets ingest the bark or wood.
• It is noted that this plant can form dense thickets. This could present a physical barrier for smaller pets or potentially harbor other plants or insects.

Considerations for Children

• The text highlights the use of the bark in tanning and dyeing, which might suggest the presence of substances that could be irritating or allergenic. Direct contact with the bark should be monitored.
• The tendency to form dense thickets may pose a minor physical hazard, especially for younger children.

Taxonomy and Nomenclature

• Scientific Name: Alnus incana (L.) Moench
• Common Names: Grey Alder, Speckled Alder, European Gray Alder, Hazel Alder, Hoary Alder, Mountain Alder, Tag Alder
• Family: Betulaceae (Birch Family)
• Synonyms: Arnus incana spp. rugosa, Alnus incana ssp. rugosa (Du Roi) J. Clausen
• Taxonomic Rank: Species, with subspecies including Alnus incana subsp. incana and Alnus incana subspecies rugosa

Distribution and Habitat

• Alnus incana is native to mainland Europe, Russia, and the Caucasus.
• It has been introduced and naturalized in North America.
• It thrives in wet soils, often bordering streams, rivers, mountain springs, moist lowlands, and swamps.
• The Gray alder is very common between the Alps and the Urals.

Ecological Role

• Alnus incana is often planted as a pioneer species in landfills, waste dumps, and to stabilize escarpments.
• It is used to reclaim derelict land and spoil heaps due to its ability to grow in poor soil conditions.
• It can be considered invasive in some regions.

Morphological Characteristics

• Alnus incana is a deciduous tree or large shrub, typically growing to 3–15 meters (10–50 feet), but can reach up to 18 meters (59 feet) or even 40-60 feet in some cases.
• It often develops multiple stems, forming dense thickets.
• The bark is thin and speckled with pores (lenticels), giving it the common name "speckled alder." The bark color can be reddish-brown with white spots.
• It flowers from February to March.
• Leaves are toothed.

Quirky Facts

• The "speckled" appearance of the bark is due to lenticels, which are spongy openings that facilitate gas exchange.
• The bark is smooth and gray even in old age.

Interactions with Other Organisms

• The bark is used in tanning and dyeing.

Further Information

• RHS (Royal Horticultural Society): Provides information on Alnus incana grey alder.
• Leafsnap: Offers images of the Gray Alder (Alnus incana), including photos of the leaf, flower, fruit, seed, petiole, bark, and tree.