North America Native Plant

Hall’s Lung Lichen

Botanical name: Lobaria hallii

USDA symbol: LOHA60

Habit: lichen

Native status: Native to North America  

Synonyms: Sticta hallii Tuck. (STHA5)   

Hall’s Lung Lichen: A Forest Treasure You Can’t Grow (But Should Appreciate) If you’ve ever wandered through the misty old-growth forests of the Pacific Northwest and noticed what looks like lettuce leaves growing on tree bark, you’ve likely encountered Hall’s lung lichen (Lobaria hallii). This fascinating organism isn’t actually a ...

Hall’s Lung Lichen: A Forest Treasure You Can’t Grow (But Should Appreciate)

If you’ve ever wandered through the misty old-growth forests of the Pacific Northwest and noticed what looks like lettuce leaves growing on tree bark, you’ve likely encountered Hall’s lung lichen (Lobaria hallii). This fascinating organism isn’t actually a plant at all—it’s a lichen, which makes it a completely different kind of garden visitor than you might expect.

What Exactly Is Hall’s Lung Lichen?

Hall’s lung lichen is a large, leafy lichen that forms impressive colonies on the bark of mature trees. Unlike plants, lichens are actually a partnership between fungi and algae working together in perfect harmony. The fungal partner provides structure and protection, while the algae partner photosynthesizes to create food for both organisms. It’s nature’s original roommate situation, and it’s been working out beautifully for millions of years!

This particular lichen gets its common name from its distinctive appearance—the large, lobed structure really does resemble lung tissue, though it’s much more attractive than that comparison might suggest. Scientifically known as Lobaria hallii, it was previously classified under the synonym Sticta hallii.

Where You’ll Find This Forest Dweller

Hall’s lung lichen is native to North America, specifically thriving in the old-growth forests of the Pacific Northwest. These lichens are incredibly picky about their living conditions—they need clean air, consistent moisture, and the stable microclimate that only mature forest ecosystems can provide.

Identifying Hall’s Lung Lichen

Spotting Hall’s lung lichen is easier than you might think once you know what to look for:

  • Large, leafy lobes that can grow several inches across
  • Blue-green to gray-green coloration when moist
  • Brownish appearance when dry
  • Smooth, somewhat wrinkled surface texture
  • Grows primarily on the bark of large, old trees
  • Often found in patches or colonies rather than as isolated specimens

Is It Beneficial to Have Around?

While you can’t exactly plant Hall’s lung lichen in your backyard herb garden, having it around is absolutely beneficial—both to the forest ecosystem and as an indicator of environmental health. These lichens are incredibly sensitive to air pollution, so their presence tells us that the air quality is excellent. They’re like nature’s air quality monitors, working for free!

In forest ecosystems, Hall’s lung lichen plays several important roles:

  • Provides nitrogen to the forest through nitrogen fixation
  • Offers nesting material for birds and small mammals
  • Serves as food for various wildlife species
  • Helps maintain forest moisture levels
  • Acts as an indicator species for old-growth forest health

Why You Can’t Grow It (And Shouldn’t Try)

Here’s the thing about Hall’s lung lichen—it’s not something you can add to your shopping cart at the local nursery. These lichens require very specific conditions that are nearly impossible to replicate outside of their natural habitat:

  • Extremely clean air (they’re highly sensitive to pollution)
  • Consistent high humidity
  • The complex microclimate of old-growth forests
  • Specific tree species and bark chemistry
  • Decades or even centuries to establish properly

Attempting to transplant or cultivate these lichens typically results in their death, and removing them from their natural habitat can damage both the lichen and the ecosystem they support.

Appreciating These Forest Gems

Instead of trying to bring Hall’s lung lichen to your garden, consider making a trip to see them in their natural habitat. Many old-growth forest preserves and national parks in the Pacific Northwest offer excellent opportunities to observe these remarkable organisms up close.

When you do encounter them, take a moment to appreciate what you’re seeing: a living partnership that’s been perfecting its collaboration for millions of years, serving as both a beautiful forest ornament and a crucial ecosystem player. It’s a reminder that some of nature’s most incredible creations can’t be domesticated—and that’s exactly what makes them so special.

So while Hall’s lung lichen won’t be joining your garden party anytime soon, knowing how to identify and appreciate these forest treasures adds another layer of wonder to your next woodland adventure. After all, the best gardens sometimes are the ones we simply get to visit rather than maintain!

Hall’s Lung Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Peltigerales

Family

Lobariaceae Chevall.

Genus

Lobaria Schreb. - lung lichen

Species

Lobaria hallii (Tuck.) Zahlbr. - Hall's lung lichen

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