North America Native Plant

Bacidina Phacodes

Botanical name: Bacidina phacodes

USDA symbol: BAPH2

Habit: lichen

Native status: Native to North America  

Synonyms: Bacidia albescens (Krempelh.) Zwackh (BAAL8)   

Bacidina phacodes: The Tiny Crusty Lichen You Might Already Have in Your Garden Ever noticed small, pale crusty patches on the bark of your trees? You might be looking at Bacidina phacodes, a fascinating lichen that’s more common than you’d think! While this little organism doesn’t have a widely-used common ...

Bacidina phacodes: The Tiny Crusty Lichen You Might Already Have in Your Garden

Ever noticed small, pale crusty patches on the bark of your trees? You might be looking at Bacidina phacodes, a fascinating lichen that’s more common than you’d think! While this little organism doesn’t have a widely-used common name, it’s definitely worth getting to know if you’re curious about the mini ecosystems thriving right in your backyard.

What Exactly Is Bacidina phacodes?

First things first – Bacidina phacodes isn’t actually a plant at all! It’s a lichen, which is a remarkable partnership between a fungus and algae (or sometimes cyanobacteria). Think of it as nature’s ultimate roommate situation where both partners benefit from living together. The fungus provides structure and protection, while the algae produces food through photosynthesis.

This particular lichen forms small, crusty patches that can appear whitish to pale gray. You’ll typically spot it growing directly on tree bark, where it looks like someone sprinkled tiny patches of rough, scaly material on the surface.

Where You’ll Find This Little Wonder

Bacidina phacodes is native to North America and can be found across various temperate regions of the continent. It’s not picky about location – you might discover it in forests, parks, or even on the trees in your own neighborhood.

Is It Beneficial to Have in Your Garden?

Absolutely! While you can’t exactly plant Bacidina phacodes (more on that in a moment), having it show up naturally in your garden is actually a great sign. Here’s why:

  • Air quality indicator: Lichens are sensitive to air pollution, so their presence suggests you have relatively clean air
  • Ecosystem support: They provide food and habitat for tiny insects and other small creatures
  • Natural beauty: They add subtle texture and interest to tree bark
  • Soil contribution: Over time, lichens help break down rock and bark, contributing to soil formation

How to Identify Bacidina phacodes

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

  • Location: Look on smooth to slightly rough tree bark
  • Appearance: Small, crusty patches that are typically pale whitish-gray
  • Texture: Rough, scaly surface that’s firmly attached to the bark
  • Size: Individual patches are usually quite small, often just a few millimeters across

Can You Grow This Lichen?

Here’s where things get interesting – you can’t really plant or cultivate Bacidina phacodes like you would a traditional garden plant. Lichens have very specific requirements and grow extremely slowly. They’ll appear on their own when conditions are just right.

However, you can encourage lichens in general by:

  • Maintaining good air quality around your property
  • Avoiding unnecessary use of chemicals that might drift onto tree bark
  • Preserving mature trees that provide good surfaces for lichen growth
  • Being patient – lichens grow incredibly slowly, sometimes just millimeters per year

A Sign of a Healthy Environment

If Bacidina phacodes shows up in your garden naturally, consider it a compliment! Its presence indicates that your local environment is healthy enough to support these sensitive organisms. Unlike some aggressive species you might worry about, this native lichen is completely harmless to trees and actually contributes to the biodiversity of your garden ecosystem.

So next time you’re wandering around your garden, take a closer look at your tree bark. You might just discover you’ve been hosting this quiet little tenant all along, silently contributing to the rich tapestry of life in your outdoor space.

Bacidina Phacodes

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Lecanoraceae Körb.

Genus

Bacidina Vezda

Species

Bacidina phacodes (Körb.) Vezda

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