North America Native Plant

Cracked Lichen

Botanical name: Acarospora terricola

USDA symbol: ACTE6

Habit: lichen

Native status: Native to North America  

Cracked Lichen: The Tiny Garden Helper You Never Knew You Had If you’ve ever noticed small, crusty patches scattered across bare soil or rock surfaces in your garden, you might have encountered cracked lichen (Acarospora terricola) without even realizing it! This fascinating little organism is actually doing some pretty amazing ...

Cracked Lichen: The Tiny Garden Helper You Never Knew You Had

If you’ve ever noticed small, crusty patches scattered across bare soil or rock surfaces in your garden, you might have encountered cracked lichen (Acarospora terricola) without even realizing it! This fascinating little organism is actually doing some pretty amazing things for your outdoor space, even though it’s probably not something you’ll find at your local nursery.

What Exactly Is Cracked Lichen?

Let’s clear up a common misconception right away – cracked lichen isn’t actually a plant at all! It’s a lichen, which is a remarkable partnership between fungi and algae working together as one organism. Think of it as nature’s ultimate roommate situation, where both partners benefit from the arrangement.

Acarospora terricola is native to North America and has adapted beautifully to some pretty harsh conditions that would make most garden plants throw in the towel.

Where You’ll Find This Little Wonder

Cracked lichen is particularly common in the western regions of North America, where it has mastered the art of thriving in arid and semi-arid environments. You’ll typically spot it in areas that most other organisms would consider less than ideal – think disturbed soils, rocky surfaces, and those forgotten corners of your yard where nothing else seems to want to grow.

Spotting Cracked Lichen in Your Garden

Identifying cracked lichen is easier than you might think once you know what to look for:

  • Small, crusty patches that look somewhat like dried, cracked mud
  • Grayish to brownish coloration that might seem unremarkable at first glance
  • Typically found on bare soil, rocks, or disturbed ground
  • Forms circular or irregular patches that can range from tiny spots to several inches across
  • Has a distinctly crusty or areolate appearance with visible cracks dividing it into small sections

Is Cracked Lichen Good for Your Garden?

Here’s where things get interesting! While you can’t exactly plant cracked lichen (it’s not for sale at garden centers), having it show up naturally in your garden is actually a pretty good sign. These little organisms are:

  • Excellent soil stabilizers, helping to prevent erosion in bare areas
  • Pioneers that help prepare harsh sites for other plants to eventually move in
  • Indicators of relatively clean air quality
  • Completely harmless to your other plants and garden features

Living With Cracked Lichen

The beauty of cracked lichen is that it requires absolutely zero care from you – in fact, it prefers to be left alone! It thrives in conditions that would stress most garden plants: poor soil, minimal water, and plenty of sun exposure. If you’re trying to establish other plants in areas where cracked lichen is growing, you can simply work around it or gently brush it aside when planting.

Since lichens grow extremely slowly and are sensitive to disturbance, try to appreciate them for the hardy survivors they are. They’re essentially living proof that nature finds a way to thrive even in the most challenging conditions.

The Bottom Line

While you won’t be adding cracked lichen to your shopping list anytime soon, spotting these crusty little patches in your garden is nothing to worry about – and might even be something to celebrate! They’re quiet garden helpers that ask for nothing while contributing to soil stability and ecosystem health. Next time you see those seemingly unremarkable crusty patches, take a moment to appreciate the amazing partnership between fungi and algae that’s been perfecting the art of survival for millions of years.

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 terricola H. Magn. - 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