North America Native Plant

Horsehair Lichen

Botanical name: Bryoria lanestris

USDA symbol: BRLA60

Habit: lichen

Native status: Native to North America  

Synonyms: Alectoria lanestris (Ach.) Gyel. (ALLA11)  ⚘  Bryopogon negativus Gyel. (BRNE3)   

Horsehair Lichen: The Mysterious Strands Decorating Your Trees If you’ve ever walked through a forest and noticed what looks like wispy, grayish hair hanging from tree branches, you’ve likely encountered horsehair lichen (Bryoria lanestris). This fascinating organism isn’t actually a plant at all – it’s a lichen, which makes it ...

Horsehair Lichen: The Mysterious Strands Decorating Your Trees

If you’ve ever walked through a forest and noticed what looks like wispy, grayish hair hanging from tree branches, you’ve likely encountered horsehair lichen (Bryoria lanestris). This fascinating organism isn’t actually a plant at all – it’s a lichen, which makes it one of nature’s most interesting partnerships!

What Exactly Is Horsehair Lichen?

Horsehair lichen is what scientists call a composite organism – it’s actually a symbiotic relationship between a fungus and an algae living together as one. The fungus provides structure and protection, while the algae produces food through photosynthesis. It’s like nature’s ultimate roommate situation that actually works!

This particular lichen gets its common name from its distinctive appearance: long, thin, pendulous strands that dangle from tree branches like coarse hair. You might also see it referred to by its scientific name, Bryoria lanestris, or its older scientific names Alectoria lanestris or Bryopogon negativus.

Where You’ll Find Horsehair Lichen

Horsehair lichen is native to North America and thrives in the cooler, more humid regions of our continent. You’re most likely to spot it in boreal and montane forests, where the air is clean and moisture levels are just right for this finicky organism.

Is Horsehair Lichen Good for Your Garden?

Here’s the thing about horsehair lichen – you can’t actually grow it in your garden, and that’s perfectly okay! This lichen is an indicator of excellent air quality, so if you’re lucky enough to have it growing naturally on trees in your area, consider it a compliment to your local environment.

While you can’t cultivate horsehair lichen, its presence in your landscape is actually quite beneficial:

  • It indicates clean, unpolluted air
  • It provides nesting material for birds
  • It adds natural, ethereal beauty to forest settings
  • It contributes to the overall ecosystem health

How to Identify Horsehair Lichen

Spotting horsehair lichen is pretty straightforward once you know what to look for:

  • Appearance: Long, thin, hair-like strands that hang down from branches
  • Color: Typically grayish-green to brownish-gray
  • Texture: Wiry and somewhat coarse to the touch
  • Location: Growing on tree bark, especially conifers
  • Length: Strands can range from a few inches to over a foot long

Creating Lichen-Friendly Conditions

While you can’t plant horsehair lichen, you can create conditions that might encourage it and other lichens to establish naturally:

  • Maintain good air quality around your property
  • Avoid using harsh chemicals or pesticides
  • Preserve mature trees, especially conifers
  • Maintain adequate humidity levels through thoughtful landscaping

The Bottom Line

Horsehair lichen is one of those wonderful organisms that you simply get to enjoy rather than actively cultivate. If you’re fortunate enough to have it growing naturally in your area, take a moment to appreciate this living indicator of environmental health. It’s a reminder that sometimes the most beautiful and beneficial aspects of our landscapes are the ones that arrive and thrive entirely on their own terms.

So next time you’re walking through a forest or even your own wooded backyard, keep an eye out for those mysterious, hair-like strands. You’ll be looking at one of nature’s most successful partnerships – and a sign that your local ecosystem is doing just fine!

Horsehair Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Parmeliaceae F. Berchtold & J. Presl

Genus

Bryoria Brodo & D. Hawksw. - horsehair lichen

Species

Bryoria lanestris (Ach.) Brodo & D. Hawksw. - horsehair lichen

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA