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Horsehair Lichen: A Detailed Look

Horsehair lichen refers to several lichen species, especially those in the genus Alectoria, characterized by a thallus (body) consisting of filaments that resemble hair. The term is also commonly used for species within the genus Bryoria.

Considerations for Pets

• Horsehair lichens often hang from trees and have a hair-like or stringy appearance. While generally not considered highly toxic, ingestion by pets might cause gastrointestinal upset.

Nomenclature and Taxonomy

• Scientific Name: The term "horsehair lichen" is applied to various species, notably those in the genus Bryoria (family Parmeliaceae) and sometimes Alectoria.
• Common Names: Horsehair lichen, tree hair lichen, black tree lichen, edible horsehair.
• Synonyms: Horsetail lichen
• Taxonomic Rank:
  • Kingdom: Fungi
  • Phylum: Ascomycota
  • Class: Lecanoromycetes
  • Order: Lecanorales
  • Family: Parmeliaceae
  • Genus: Bryoria

Distribution and Habitat

• Horsehair lichens have a widespread distribution, particularly in boreal and cool temperate areas.
• They are often found hanging from conifers (and less frequently hardwoods) in old-growth forest habitats.
• Specific locations mentioned include eastern Washington and the inland temperate rainforests.

Morphological Characteristics

• Horsehair lichens are composed of intricately branched filaments.
• The thallus can be long and range in color from pale gray to dark smoky brown, hanging in clumps.
• Slender strands may contain long narrow slits on the surface.

Quirky Facts

• Some species of horsehair lichen, such as Bryoria fremontii, were traditionally used as a food source by indigenous peoples like the Kootenais, Salish, and Blackfeet.