North America Native Plant

Smooth Melanelia Lichen

Botanical name: Melanelia glabra

USDA symbol: MEGL5

Habit: lichen

Native status: Native to North America  

Synonyms: Parmelia glabra (Schaerer) Nyl. (PAGL11)   

Smooth Melanelia Lichen: The Quiet Garden Guardian You Never Knew You Had Have you ever noticed those gray, crusty patches adorning the bark of trees in your yard? Meet the smooth melanelia lichen (Melanelia glabra), a fascinating organism that’s probably been quietly living in your garden ecosystem without you even ...

Smooth Melanelia Lichen: The Quiet Garden Guardian You Never Knew You Had

Have you ever noticed those gray, crusty patches adorning the bark of trees in your yard? Meet the smooth melanelia lichen (Melanelia glabra), a fascinating organism that’s probably been quietly living in your garden ecosystem without you even realizing it. This unassuming North American native plays a surprisingly important role in your outdoor space.

What Exactly Is a Lichen?

Before we dive into the specifics of smooth melanelia, let’s clear up what a lichen actually is. Unlike plants, lichens are composite organisms made up of fungi and algae (or cyanobacteria) living together in a mutually beneficial relationship. Think of them as nature’s perfect roommates – the fungus provides structure and protection, while the algae produces food through photosynthesis.

Melanelia glabra, also known by its scientific synonym Parmelia glabra, is a crustose lichen, meaning it forms a crust-like layer that’s tightly attached to its substrate.

Where You’ll Find Smooth Melanelia

This hardy lichen is native to North America and can be found across much of the continent. It’s particularly common in temperate regions where it colonizes tree bark, rocks, and occasionally wooden structures like fences or decks.

Identifying Smooth Melanelia in Your Garden

Spotting smooth melanelia lichen is easier than you might think once you know what to look for:

  • Forms gray to brownish-gray crusty patches on tree bark
  • Surface appears relatively smooth compared to other crusty lichens
  • Tightly adheres to the bark surface
  • Often found on the bark of deciduous trees and conifers
  • May have small, darker spots (fruiting bodies) scattered across the surface

Is Smooth Melanelia Beneficial for Your Garden?

Absolutely! While you can’t plant or cultivate smooth melanelia lichen (it grows naturally where conditions are right), its presence is actually a wonderful sign for your garden:

  • Air quality indicator: Lichens are sensitive to air pollution, so their presence indicates relatively clean air in your area
  • Ecosystem health: They contribute to biodiversity and create microhabitats for tiny creatures
  • Natural beauty: Adds authentic texture and character to tree bark
  • Soil building: As lichens slowly break down, they help create soil and provide nutrients

Should You Be Concerned About Lichens on Your Trees?

Here’s some good news: lichens don’t harm healthy trees! They’re epiphytes, meaning they simply use the tree as a surface to grow on without parasitizing it. If you notice lichens on your trees, it’s generally a sign of a healthy ecosystem rather than a problem.

However, if you see lichens suddenly appearing on branches that are dying back, the lichen isn’t the cause – it’s likely that the tree was already stressed by other factors like disease, drought, or age.

Living with Lichens in Your Garden

Since you can’t cultivate smooth melanelia lichen, the best approach is to appreciate it as part of your garden’s natural ecosystem. Here are some ways to coexist happily:

  • Avoid using harsh chemicals or pressure washing tree bark where lichens grow
  • Maintain good air quality around your property
  • Allow dead branches with interesting lichen growth to remain as habitat (if safe to do so)
  • Consider lichens as free, low-maintenance garden decoration

The Bottom Line

Smooth melanelia lichen might not be the showiest addition to your garden, but it’s certainly one of the most fascinating. This quiet North American native serves as a living indicator of your garden’s environmental health while adding subtle natural beauty to tree bark and rocks. Rather than trying to remove or control it, embrace smooth melanelia as a sign that your garden is supporting a diverse and healthy ecosystem.

Next time you’re strolling through your yard, take a moment to appreciate these remarkable composite organisms. They’ve been perfecting their symbiotic lifestyle for millions of years – and they’re happy to call your garden home.

Smooth Melanelia 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

Melanelia Essl. - melanelia lichen

Species

Melanelia glabra (Schaerer) Essl. - smooth melanelia lichen

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