North America Native Plant

Heufler’s Cracked Lichen

Botanical name: Acarospora heufleriana

USDA symbol: ACHE7

Habit: lichen

Native status: Native to North America  

Heufler’s Cracked Lichen: A Fascinating Natural Wonder in Your Landscape Have you ever noticed those crusty, puzzle-piece-like patches growing on rocks in your garden or natural areas? You might be looking at Heufler’s cracked lichen (Acarospora heufleriana), a remarkable organism that’s neither plant nor animal, but something wonderfully unique in ...

Heufler’s Cracked Lichen: A Fascinating Natural Wonder in Your Landscape

Have you ever noticed those crusty, puzzle-piece-like patches growing on rocks in your garden or natural areas? You might be looking at Heufler’s cracked lichen (Acarospora heufleriana), a remarkable organism that’s neither plant nor animal, but something wonderfully unique in between!

What Exactly Is Heufler’s Cracked Lichen?

Despite its name suggesting it’s a plant, Heufler’s cracked lichen is actually a fascinating partnership between fungi and algae working together in perfect harmony. This symbiotic relationship creates what we see as a lichen – a crusty, patch-like organism that decorates rock surfaces with its distinctive cracked appearance.

The cracked part of its name comes from its areolate growth pattern, where the lichen surface breaks into small, puzzle-piece-like sections separated by dark lines. These patches typically appear grayish to brownish and can range from just a few millimeters to several centimeters across.

Where You’ll Find This Native Wonder

Acarospora heufleriana is a proud North American native, particularly thriving in the arid and semi-arid regions of the western United States. You’re most likely to spot it growing on calcareous rocks – those limestone and other calcium-rich stone surfaces that provide the perfect foundation for this hardy organism.

Is It Beneficial to Your Garden?

While you can’t exactly plant Heufler’s cracked lichen like you would a flower or shrub, its presence in your landscape is actually quite beneficial:

  • Acts as a natural air quality indicator – lichens are sensitive to pollution, so their presence suggests clean air
  • Contributes to biodiversity in your garden ecosystem
  • Helps prevent soil erosion by stabilizing rock surfaces
  • Adds unique textural interest to rock gardens and natural stone features
  • Requires absolutely no maintenance – nature’s ultimate low-care addition!

How to Identify Heufler’s Cracked Lichen

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

  • Look for crusty, flat patches growing directly on rock surfaces
  • Notice the distinctive cracked or areolate pattern that gives it its common name
  • Color ranges from light gray to brownish, sometimes with a slightly yellowish tint
  • Typically found on calcareous rocks in sunny to partially shaded locations
  • Patches can be small (a few millimeters) or grow together to cover larger areas

Creating Lichen-Friendly Conditions

While you can’t plant lichens, you can certainly encourage them to naturally colonize your landscape:

  • Include natural stone features, especially limestone or other calcium-rich rocks
  • Maintain good air quality around your property
  • Avoid using chemical treatments on or near rock surfaces
  • Allow natural weathering processes to occur on stone surfaces
  • Be patient – lichens grow very slowly and may take years to establish

A Word of Caution and Appreciation

If you’re lucky enough to have Heufler’s cracked lichen naturally occurring in your landscape, consider yourself blessed with a piece of living natural history. These organisms grow incredibly slowly – sometimes just millimeters per year – so any patches you see may have taken decades or even centuries to develop.

Rather than trying to remove or relocate lichens, embrace them as indicators of a healthy, unpolluted environment. They’re living proof that your garden space supports clean air and natural biodiversity!

Next time you’re walking through your garden or exploring natural areas, take a moment to appreciate these remarkable organisms. Heufler’s cracked lichen may not have showy flowers or dramatic seasonal changes, but it represents one of nature’s most successful partnerships – and that’s pretty amazing in our book!

Heufler’s Cracked Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Acarosporaceae Zahlbr.

Genus

Acarospora A. Massal. - cracked lichen

Species

Acarospora heufleriana Körb. - Heufler's cracked lichen

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