North America Native Plant

Pseudoparmelia

Botanical name: Pseudoparmelia sphaerospora

USDA symbol: PSSP5

Habit: lichen

Native status: Native to North America  

Synonyms: Parmelia congruens Ach. (PACO39)  ⚘  Parmelia cubensis Nyl. (PACU5)  ⚘  Parmelia endoxanthoa G. Merr. (PAEN6)  ⚘  Parmelia leucochlora Tuck. (PALE17)  ⚘  Parmelia sphaerospora Nyl. (PASP11)   

Pseudoparmelia: The Fascinating Foliose Lichen in Your Backyard If you’ve ever noticed grayish-green, leaf-like patches growing on tree bark in your yard, you might have encountered pseudoparmelia (Pseudoparmelia sphaerospora). But before you start wondering how to plant or care for this intriguing organism, here’s the plot twist: it’s not actually ...

Pseudoparmelia: The Fascinating Foliose Lichen in Your Backyard

If you’ve ever noticed grayish-green, leaf-like patches growing on tree bark in your yard, you might have encountered pseudoparmelia (Pseudoparmelia sphaerospora). But before you start wondering how to plant or care for this intriguing organism, here’s the plot twist: it’s not actually a plant at all!

What Exactly is Pseudoparmelia?

Pseudoparmelia sphaerospora is a foliose lichen – a remarkable partnership between a fungus and algae (or sometimes cyanobacteria) living together in perfect harmony. This dynamic duo creates what looks like a crusty, leaf-like organism that you’ll typically find making itself at home on tree bark.

This lichen goes by several scientific aliases, including Parmelia congruens, Parmelia cubensis, and Parmelia leucochlora, but pseudoparmelia is the name that’s stuck around most commonly.

Where You’ll Find This Natural Wonder

As a native species to North America, pseudoparmelia has been quietly doing its thing on trees across the continent long before any of us started thinking about native gardening. You’ll most commonly spot it in eastern and southeastern regions, where the humidity levels are just right for lichen life.

How to Identify Pseudoparmelia

Spotting pseudoparmelia is easier than you might think once you know what to look for:

  • Gray-green to bluish-gray coloration that can appear almost silvery in certain light
  • Foliose (leaf-like) structure that forms rosette-like patches
  • Grows flat against tree bark, creating distinctive crusty patches
  • Typically found on the bark of hardwood trees
  • Forms circular or irregular patches that can expand over time

Is Pseudoparmelia Beneficial for Your Garden?

Here’s where things get interesting! While you can’t exactly plant pseudoparmelia in your garden bed, its presence is actually a fantastic sign for your outdoor space. Think of lichens like pseudoparmelia as nature’s air quality monitors – they’re incredibly sensitive to air pollution, so finding them thriving in your area means you’ve got relatively clean air.

Pseudoparmelia and other lichens also play important ecological roles:

  • They don’t harm the trees they grow on (they’re epiphytes, not parasites)
  • They contribute to nutrient cycling in forest ecosystems
  • Some wildlife may use them for nesting materials
  • They add natural texture and visual interest to tree bark

Can You Cultivate Pseudoparmelia?

Sorry to burst any cultivation bubbles, but pseudoparmelia isn’t something you can plant, water, or fertilize. These lichens appear naturally when conditions are just right – clean air, appropriate humidity levels, and suitable tree hosts. Trying to grow them would be like trying to grow a rainbow!

The best thing you can do to encourage lichens like pseudoparmelia in your outdoor spaces is to maintain a healthy ecosystem with mature trees and avoid using chemicals that might compromise air quality.

Appreciating Nature’s Partnership

While pseudoparmelia might not fit into traditional garden design plans, discovering it growing naturally in your yard is worth celebrating. It’s a sign that your outdoor space is supporting diverse life forms and maintaining good environmental health.

Next time you’re walking around your property, take a moment to look up at the tree bark around you. You might be surprised by the intricate world of lichens that’s been quietly thriving right under your nose. Pseudoparmelia and its lichen cousins remind us that some of nature’s most fascinating partnerships happen without any help from us gardeners – and sometimes, that’s exactly how it should be.

Pseudoparmelia

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

Pseudoparmelia Lynge - pseudoparmelia

Species

Pseudoparmelia sphaerospora (Nyl.) Hale - pseudoparmelia

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