North America Native Plant

Schaerer’s Psorotichia Lichen

Botanical name: Psorotichia schaereri

USDA symbol: PSSC9

Habit: lichen

Native status: Native to North America  

Synonyms: Pyrenopsis schaereri A. Massal. (PYSC2)   

Schaerer’s Psorotichia Lichen: A Tiny Natural Wonder in Your Garden If you’ve ever noticed small, crusty patches growing on rocks or soil in your garden and wondered what they were, you might have encountered a fascinating organism that’s neither plant nor animal – a lichen! Today, we’re diving into the ...

Schaerer’s Psorotichia Lichen: A Tiny Natural Wonder in Your Garden

If you’ve ever noticed small, crusty patches growing on rocks or soil in your garden and wondered what they were, you might have encountered a fascinating organism that’s neither plant nor animal – a lichen! Today, we’re diving into the world of Schaerer’s psorotichia lichen (Psorotichia schaereri), a native North American species that might be quietly calling your garden home without you even knowing it.

What Exactly Is Schaerer’s Psorotichia Lichen?

Schaerer’s psorotichia lichen is a unique organism that represents one of nature’s most successful partnerships. Like all lichens, it’s actually two organisms living together: a fungus and an algae (or sometimes cyanobacteria) working as a team. The fungus provides structure and protection, while the algae produces food through photosynthesis. It’s like having the ultimate roommate situation that’s been working perfectly for millions of years!

This particular lichen species is native to North America, making it a legitimate part of our continent’s natural heritage. You might also see it referenced in scientific literature under its synonym, Pyrenopsis schaereri A. Massal., but don’t let the fancy names intimidate you.

Where Does It Live?

While Psorotichia schaereri is confirmed to be native to North America, specific details about its exact geographic range remain somewhat mysterious in the scientific literature. Like many lichens, it likely has a broader distribution than we currently understand, quietly existing in suitable habitats across the continent.

Is It Good for Your Garden?

Here’s the cool thing about having lichens like Schaerer’s psorotichia in your garden – they’re actually excellent indicators of environmental health! Lichens are incredibly sensitive to air pollution, so their presence suggests you have relatively clean air. Think of them as nature’s air quality monitors, working for free in your backyard.

While you can’t exactly plant or cultivate lichens the way you would a flower or shrub, you can create conditions that make them feel welcome:

  • Avoid using harsh chemical pesticides and fertilizers
  • Maintain good air quality around your property
  • Leave some undisturbed areas with rocks, old wood, or bare soil
  • Resist the urge to clean every surface – lichens need places to establish

How to Identify Schaerer’s Psorotichia Lichen

Identifying specific lichen species can be tricky, even for experts, and Schaerer’s psorotichia lichen is no exception. Without detailed morphological studies and sometimes even DNA analysis, definitive identification of many lichen species requires specialized knowledge and equipment.

If you suspect you have lichens in your garden (and you probably do!), look for:

  • Small, crusty or patch-like growths on rocks, soil, or other surfaces
  • Colors that might range from gray to brown to greenish
  • Growth that seems permanently attached to its substrate
  • Organisms that don’t look quite like typical plants or fungi

The Bottom Line

Schaerer’s psorotichia lichen represents just one small piece of the incredible diversity of native organisms that might be sharing your garden space. While you can’t buy it at a nursery or plant it from seed, you can appreciate it as part of North America’s natural heritage and create conditions that support lichen communities in general.

Rather than trying to eliminate these fascinating organisms, consider them welcomed guests that indicate your garden is part of a healthy ecosystem. After all, any organism that’s mastered the art of cooperation for millions of years probably has something to teach us about successful partnerships!

The next time you’re wandering through your garden, take a moment to look closely at those crusty patches on rocks or bare soil. You might just be looking at Schaerer’s psorotichia lichen or one of its many lichen relatives – tiny but remarkable examples of nature’s ingenuity right in your own backyard.

Schaerer’s Psorotichia Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lichinales

Family

Lichinaceae Nyl.

Genus

Psorotichia A. Massal. - psorotichia lichen

Species

Psorotichia schaereri (A. Massal.) Arnold - Schaerer's psorotichia lichen

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