North America Native Plant

American Horsehair Lichen

Botanical name: Bryoria trichodes americana

USDA symbol: BRTRA

Habit: lichen

Native status: Native to North America  

Synonyms: Alectoria americana Mot. (ALAM10)  ⚘  Alectoria ambigua Mot. (ALAM9)   

American Horsehair Lichen: Nature’s Hanging Garden Ornament If you’ve ever wandered through a forest and noticed what looks like wispy hair hanging from tree branches, you might have encountered the fascinating American horsehair lichen (Bryoria trichodes americana). This isn’t a plant you can pick up at your local nursery, but ...

American Horsehair Lichen: Nature’s Hanging Garden Ornament

If you’ve ever wandered through a forest and noticed what looks like wispy hair hanging from tree branches, you might have encountered the fascinating American horsehair lichen (Bryoria trichodes americana). This isn’t a plant you can pick up at your local nursery, but it’s definitely worth knowing about – especially if you’re curious about the amazing life forms that might already be decorating the trees in your area!

What Exactly Is American Horsehair Lichen?

Let’s clear up a common misconception right away: despite its name, American horsehair lichen isn’t actually a plant at all! It’s a lichen, which is a remarkable partnership between a fungus and an algae (or sometimes a cyanobacteria). Think of it as nature’s ultimate roommate situation – the fungus provides structure and protection, while the algae handles the food production through photosynthesis.

This particular lichen gets its horsehair nickname from its distinctive appearance. It forms long, thin, hair-like strands that dangle gracefully from tree branches, creating an almost ethereal forest atmosphere. The strands can range from grayish-green to brownish in color, and they sway gently in the breeze like nature’s own wind chimes.

Where You’ll Find This Woodland Wonder

American horsehair lichen is native to North America, where it naturally occurs in forest environments. You’re most likely to spot it hanging from the branches of various trees, particularly in areas with clean air – lichens are notoriously sensitive to air pollution, making them excellent environmental indicators.

This lichen has also been known by other scientific names throughout history, including Alectoria americana and Alectoria ambigua, so don’t be confused if you see these names in older field guides or botanical references.

Is It Beneficial to Have in Your Garden?

Here’s the thing about American horsehair lichen – you can’t actually plant it or cultivate it in your garden. But if you’re lucky enough to have it show up naturally on your trees, consider yourself blessed! Here’s why:

  • Air quality indicator: Its presence suggests you have clean, unpolluted air in your area
  • Natural beauty: It adds a mystical, forest-like quality to mature trees
  • Wildlife habitat: Many birds use lichen strands as nesting material
  • Ecosystem health: It’s part of a healthy, functioning forest ecosystem

How to Identify American Horsehair Lichen

Spotting this lichen is fairly straightforward once you know what to look for:

  • Appearance: Long, thin, hair-like strands hanging from tree branches
  • Color: Typically grayish-green to brownish, sometimes with a slight yellowish tinge
  • Texture: The strands feel somewhat coarse and dry to the touch
  • Growth pattern: Hangs in curtain-like clusters from branches
  • Habitat: Usually found on deciduous and coniferous trees in forested areas

What This Means for Your Landscape

If American horsehair lichen appears naturally on your trees, resist any urge to remove it! It’s not harming your trees – in fact, it’s simply using them as a support structure. The lichen doesn’t take nutrients from the tree like a parasite would.

Instead, view it as a sign that your property supports a healthy, diverse ecosystem. If you want to encourage lichens in your landscape, focus on:

  • Reducing air pollution in your area
  • Avoiding unnecessary pesticide use
  • Maintaining mature trees that can serve as lichen habitat
  • Preserving natural forest conditions where possible

The Bottom Line

American horsehair lichen isn’t something you can add to your shopping list, but it might just add itself to your landscape if conditions are right. Consider it nature’s way of giving your trees a wild, woodland makeover – and a gentle reminder that the healthiest gardens are often the ones that welcome unexpected natural visitors.

So next time you’re walking through your yard or a nearby forest, take a moment to look up. You might just spot these graceful strands swaying in the breeze, quietly doing their part to make the world a more beautiful and ecologically rich place.

American 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 trichodes (Michx.) 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