North America Native Plant

Matted Lichen

Botanical name: Pannaria pezizoides

USDA symbol: PAPE60

Habit: lichen

Native status: Native to North America  

Matted Lichen: The Quiet Champion of Clean Air in Your Garden If you’ve ever noticed thin, crusty patches on tree bark or rocks in your garden and wondered what they were, you might have encountered the humble matted lichen (Pannaria pezizoides). This fascinating organism is more than just a simple ...

Matted Lichen: The Quiet Champion of Clean Air in Your Garden

If you’ve ever noticed thin, crusty patches on tree bark or rocks in your garden and wondered what they were, you might have encountered the humble matted lichen (Pannaria pezizoides). This fascinating organism is more than just a simple growth on surfaces – it’s actually a remarkable partnership between fungi and algae that can tell you a lot about the health of your local environment.

What Exactly Is Matted Lichen?

Matted lichen isn’t a plant in the traditional sense. Instead, it’s a composite organism made up of fungi and algae living together in perfect harmony. The fungal partner provides structure and protection, while the algae contribute food through photosynthesis. This incredible partnership creates those thin, mat-like crusts you see spreading across tree bark and rock surfaces.

Pannaria pezizoides typically appears as grayish to brownish patches that form relatively flat, crusty mats. These patches can vary in size and often blend seamlessly with their surroundings, making them easy to overlook unless you’re specifically looking for them.

Where You’ll Find This Native Beauty

This lichen is native to North America and can be found across temperate regions of the continent. It’s particularly fond of settling on the bark of mature trees and occasionally on rocks, where it can access the right amount of moisture and light without being too exposed to harsh conditions.

Why Matted Lichen Is Actually Great for Your Garden

While you can’t plant matted lichen like you would a flower or shrub, its presence in your garden is actually something to celebrate. Here’s why:

  • Air quality indicator: Lichens are incredibly sensitive to air pollution, so finding them in your garden means you have relatively clean air
  • Natural character: They add an authentic, aged look to mature trees and stone features
  • Ecosystem support: While they don’t directly feed pollinators, they contribute to overall ecosystem health
  • Low maintenance beauty: Once established, they require absolutely no care from you

How to Identify Matted Lichen

Spotting Pannaria pezizoides in your garden is easier once you know what to look for:

  • Look for thin, mat-like crusts on tree bark or rocks
  • Colors range from grayish to brownish, sometimes with subtle variations
  • The surface appears relatively flat and crusty
  • Often found on the north or shaded sides of trees where moisture levels are more consistent
  • May appear in patches of various sizes, sometimes merging with other lichen species

Creating Lichen-Friendly Conditions

While you can’t actively grow matted lichen, you can create conditions that make your garden more welcoming to these beneficial organisms:

  • Maintain mature trees with textured bark
  • Avoid using harsh chemicals or pesticides that could affect air quality
  • Keep some areas of your garden naturally wild and undisturbed
  • Include natural stone features like rock walls or boulders
  • Ensure good air circulation throughout your landscape

The Bottom Line

Matted lichen might not be the showstopper that draws visitors to your garden, but it’s definitely worth appreciating. Think of it as nature’s stamp of approval – a quiet indicator that your outdoor space is healthy and well-balanced. Rather than trying to remove these fascinating organisms, consider them a sign that you’re doing something right in creating a natural, sustainable garden environment.

Next time you’re wandering through your garden, take a moment to look closely at your trees and rocks. You might be surprised by the intricate world of lichens that’s been quietly thriving right under your nose!

Matted Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Pannariaceae Tuck.

Genus

Pannaria Delise - matted lichen

Species

Pannaria pezizoides (Weber) Trevis. - matted lichen

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