North America Native Plant

Greenland Rim Lichen

Botanical name: Lecanora groenlandica

USDA symbol: LEGR13

Habit: lichen

Native status: Native to North America  

Discovering Greenland Rim Lichen: A Hardy Arctic Survivor in Your Landscape If you’ve ever wondered about those crusty, pale patches you might spot on rocks during hikes in northern regions, you may have encountered the fascinating world of lichens. Meet Lecanora groenlandica, commonly known as Greenland rim lichen – a ...

Discovering Greenland Rim Lichen: A Hardy Arctic Survivor in Your Landscape

If you’ve ever wondered about those crusty, pale patches you might spot on rocks during hikes in northern regions, you may have encountered the fascinating world of lichens. Meet Lecanora groenlandica, commonly known as Greenland rim lichen – a remarkable organism that’s far more interesting than its humble appearance might suggest.

What Exactly Is Greenland Rim Lichen?

First things first: Greenland rim lichen isn’t actually a plant at all! It’s a lichen, which means it’s a symbiotic partnership between a fungus and algae (or sometimes cyanobacteria). This dynamic duo works together to create what looks like a single organism, but it’s actually two different life forms sharing resources and helping each other survive in some pretty harsh conditions.

Lecanora groenlandica appears as grayish-white to pale yellowish crusty patches that spread across rock surfaces. These aren’t the leafy, branching lichens you might be more familiar with – instead, they form what scientists call a crustose growth pattern, meaning they’re tightly attached to their rocky homes like a living coat of paint.

Where Does This Arctic Wonder Call Home?

As its common name suggests, Greenland rim lichen is native to some pretty chilly places. This tough little organism calls the arctic and subarctic regions of North America home, thriving in areas like Greenland, northern Canada, and Alaska. It’s perfectly adapted to life in places where most other organisms would throw in the towel.

Can You Grow Greenland Rim Lichen in Your Garden?

Here’s where we need to manage expectations: you can’t actually cultivate or plant Greenland rim lichen in your garden. Unlike traditional plants that you can buy at a nursery, lichens are incredibly complex organisms that require very specific environmental conditions to survive. They need:

  • Extremely cold climates
  • Clean, unpolluted air
  • Specific rock substrates
  • Particular moisture and temperature cycles

Trying to grow this lichen would be like trying to relocate a polar bear to your backyard – it’s just not going to work out well for anyone involved!

Is Greenland Rim Lichen Beneficial to Have Around?

While you can’t cultivate it, if you’re lucky enough to spot Greenland rim lichen in its natural habitat, it’s actually performing some pretty important ecological functions:

  • It helps break down rock surfaces over time, contributing to soil formation
  • It serves as a food source for some arctic wildlife, particularly caribou and reindeer
  • It acts as a natural air quality indicator – lichens are very sensitive to pollution
  • It provides microscopic habitat for tiny organisms

How to Identify Greenland Rim Lichen

If you’re exploring northern regions and want to spot this hardy survivor, here’s what to look for:

  • Crusty, flat patches on rock surfaces
  • Grayish-white to pale yellow coloration
  • Smooth to slightly rough texture
  • Tightly adhered to the rock (you can’t peel it off easily)
  • Found in arctic and subarctic environments

The Bottom Line for Gardeners

While Greenland rim lichen won’t be joining your garden party anytime soon, it’s worth appreciating for what it is: an incredible example of nature’s ability to adapt and survive in extreme conditions. If you encounter it during your outdoor adventures, take a moment to marvel at this ancient partnership between fungus and algae that’s been perfecting the art of survival for millions of years.

For gardeners interested in supporting native ecosystems, focus on native plants that are actually suited to your climate zone and can provide real benefits to local wildlife. Your local extension office can help you identify native alternatives that will thrive in your specific growing conditions while supporting the pollinators and wildlife in your area.

Greenland Rim Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Lecanoraceae Körb.

Genus

Lecanora Ach. - rim lichen

Species

Lecanora groenlandica Lynge - Greenland rim lichen

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