North America Native Plant

Carolina Thelomma Lichen

Botanical name: Thelomma carolinianum

USDA symbol: THCA8

Habit: lichen

Native status: Native to North America  

Synonyms: Cyphelium carolinianum (Tuck.) Zahlbr. (CYCA21)   

Carolina Thelomma Lichen: A Tiny Natural Wonder in Your Backyard Have you ever noticed small, crusty patches on tree bark and wondered what they were? You might have been looking at the Carolina thelomma lichen (Thelomma carolinianum), a fascinating organism that’s neither plant nor animal, but something wonderfully in between! ...

Carolina Thelomma Lichen: A Tiny Natural Wonder in Your Backyard

Have you ever noticed small, crusty patches on tree bark and wondered what they were? You might have been looking at the Carolina thelomma lichen (Thelomma carolinianum), a fascinating organism that’s neither plant nor animal, but something wonderfully in between!

What Exactly Is Carolina Thelomma Lichen?

Before we dive deeper, let’s clear up what a lichen actually is. Lichens are remarkable partnerships between fungi and algae (or sometimes cyanobacteria) that work together in perfect harmony. The fungus provides structure and protection, while the algae produces food through photosynthesis. It’s like nature’s ultimate roommate situation!

Carolina thelomma lichen is a small, crusty species that belongs to this incredible group of organisms. You might also see it referred to by its scientific synonym, Cyphelium carolinianum, in older field guides.

Where You’ll Find This Native Beauty

This lichen is native to North America and can be found throughout the eastern United States, with a particular fondness for the southeastern regions. It makes its home on the bark of hardwood trees, where it quietly goes about its business of being amazing.

Spotting Carolina Thelomma in the Wild

Identifying Carolina thelomma lichen takes a keen eye, as it’s quite small. Here’s what to look for:

  • Small, crusty patches on tree bark
  • Distinctive cup-shaped fruiting bodies (called apothecia) when mature
  • Typically found on hardwood trees
  • Grayish to brownish coloration

Remember, lichens grow very slowly, so what you’re seeing may have been developing for years or even decades!

Is Carolina Thelomma Beneficial for Your Garden?

While you can’t exactly plant Carolina thelomma lichen in your garden like you would a tomato or rose bush, its presence is actually a wonderful sign! Lichens are incredibly sensitive to air pollution, so finding them in your yard means you have clean, healthy air.

Here’s why having lichens around is fantastic:

  • They indicate good air quality
  • They don’t harm trees – they’re just hitchhiking on the bark
  • They add biodiversity to your local ecosystem
  • They provide tiny habitats for microscopic creatures

Can You Grow Carolina Thelomma Lichen?

Here’s where things get interesting – you can’t actually cultivate lichens like traditional garden plants. They can’t be planted, watered, or fertilized. They grow at their own pace, in their own time, and only where conditions are just right.

Instead of trying to grow them, the best thing you can do is:

  • Maintain clean air around your property
  • Avoid using harsh chemicals near trees
  • Let nature take its course
  • Simply appreciate them when you spot them

A Living Partnership Worth Celebrating

Carolina thelomma lichen might not add splash of color to your flower beds or attract butterflies to your garden, but it represents something equally beautiful – the incredible partnerships that exist in nature. These tiny organisms remind us that sometimes the most amazing things come in the smallest packages.

Next time you’re wandering around your yard or local park, take a moment to look closely at tree bark. You might just spot these remarkable little partnerships quietly thriving in their own unique way. And remember, if you see lichens, you’re looking at a sign of a healthy environment – and that’s something worth celebrating!

Carolina Thelomma Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Caliciales

Family

Caliciaceae Chevall.

Genus

Thelomma A. Massal. - thelomma lichen

Species

Thelomma carolinianum (Tuck.) Tibell - Carolina thelomma lichen

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