North America Native Plant

Farinose Crabseye Lichen

Botanical name: Ochrolechia farinacea

USDA symbol: OCFA

Habit: lichen

Native status: Native to North America  

Farinose Crabseye Lichen: A Fascinating Garden Visitor You Can’t Plant Have you ever noticed pale, crusty patches decorating the bark of your favorite oak or maple tree? Meet the farinose crabseye lichen (Ochrolechia farinacea), a remarkable organism that’s probably been quietly living in your garden longer than you have! This ...

Farinose Crabseye Lichen: A Fascinating Garden Visitor You Can’t Plant

Have you ever noticed pale, crusty patches decorating the bark of your favorite oak or maple tree? Meet the farinose crabseye lichen (Ochrolechia farinacea), a remarkable organism that’s probably been quietly living in your garden longer than you have! This native North American species is one of nature’s most interesting partnerships, and while you can’t exactly plant it, understanding what it is and why it matters might just change how you look at your trees.

What Exactly Is a Lichen?

Here’s where things get wonderfully weird: lichens aren’t plants at all! The farinose crabseye lichen is actually a symbiotic partnership between a fungus and algae (and sometimes bacteria too). Think of it as nature’s ultimate roommate situation – the fungus provides structure and protection, while the algae produces food through photosynthesis. It’s a win-win arrangement that’s been working beautifully for millions of years.

Where You’ll Find This Native Beauty

As a native species to North America, Ochrolechia farinacea has made itself at home across boreal and temperate regions of the continent. You’re most likely to spot it in woodland areas, parks, and mature gardens where it quietly colonizes the bark of deciduous trees and occasionally rocks.

Identifying Farinose Crabseye Lichen

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

  • Appearance: Forms whitish-gray to pale yellowish crusty patches (called a crustose form)
  • Texture: Has a somewhat powdery or farinose surface (hence the name!)
  • Location: Typically found on tree bark, especially hardwoods like oaks and maples
  • Size: Individual patches can range from small spots to several inches across
  • Reproductive structures: Look for small, round, disc-like structures called apothecia

Why This Lichen Is Actually Great for Your Garden

Before you start worrying about these crusty patches infecting your trees, here’s some great news: lichens don’t harm their host plants at all! In fact, having farinose crabseye lichen in your garden is actually a good sign:

  • Air quality indicator: Lichens are sensitive to air pollution, so their presence suggests you have relatively clean air
  • Ecosystem health: They contribute to biodiversity and provide microhabitats for tiny creatures
  • Natural beauty: They add authentic, wild character to mature trees and garden spaces
  • Low maintenance: They require absolutely no care from you!

The You Can’t Plant It Reality

Here’s the thing about lichens that might disappoint eager gardeners: you can’t simply go to a nursery and buy some farinose crabseye lichen to install in your landscape. These organisms establish themselves naturally over time, and attempting to transplant or cultivate them rarely succeeds. They’re incredibly slow-growing and have very specific requirements that are difficult to replicate artificially.

How to Encourage Lichens Naturally

While you can’t plant lichens directly, you can create conditions that make them more likely to appear:

  • Maintain mature trees with textured bark
  • Avoid using harsh chemicals or fungicides in your garden
  • Keep air circulation good around trees
  • Be patient – lichens can take years or even decades to establish
  • Avoid scraping or removing existing lichens from tree bark

Living in Harmony with Your Lichen Neighbors

The best approach to farinose crabseye lichen is simply to appreciate it for what it is: a sign of a healthy, natural ecosystem right in your own backyard. These fascinating organisms ask nothing from you except to be left alone to do their slow, quiet work of adding character and ecological value to your garden spaces.

Next time you’re strolling through your garden, take a moment to examine the bark of your trees more closely. You might just discover you’ve been hosting these remarkable partnerships all along – and that’s something worth celebrating in any nature-loving garden!

Farinose Crabseye Lichen

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Lecanorales

Family

Pertusariaceae Körb.

Genus

Ochrolechia A. Massal. - crabseye lichen

Species

Ochrolechia farinacea Howard - farinose crabseye lichen

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