North America Native Plant

Coenogonium Missouriense

Botanical name: Coenogonium missouriense

USDA symbol: COMI14

Habit: lichen

Native status: Native to North America  

Coenogonium missouriense: The Mysterious Missouri Lichen in Your Garden Have you ever noticed thin, whitish-gray patches scattered across tree bark in your yard and wondered what they might be? You might be looking at Coenogonium missouriense, a fascinating native lichen that’s more common than you’d think – though you probably ...

Coenogonium missouriense: The Mysterious Missouri Lichen in Your Garden

Have you ever noticed thin, whitish-gray patches scattered across tree bark in your yard and wondered what they might be? You might be looking at Coenogonium missouriense, a fascinating native lichen that’s more common than you’d think – though you probably never knew it had a name!

What Exactly Is Coenogonium missouriense?

Before we dive in, let’s clear up what we’re dealing with here. Coenogonium missouriense isn’t a plant you can pick up at your local nursery – it’s actually a lichen. Think of lichens as nature’s ultimate partnership: they’re made up of fungi and algae living together in perfect harmony. The fungus provides structure and protection, while the algae do the photosynthesis heavy lifting. It’s like having the world’s most efficient roommate situation!

This particular lichen forms thin, crusty patches that might remind you of dried paint or natural graffiti on tree bark. It’s what scientists call a crustose lichen, meaning it grows flat against its host surface like a living coat of paint.

Where You’ll Find This Native Beauty

Coenogonium missouriense is a proud native of North America, with documented populations throughout the eastern regions of the continent. As its name suggests, it was first scientifically described from specimens found in Missouri, but don’t let that fool you – this lichen has likely been quietly decorating trees across much of eastern North America for centuries.

Is It Good for Your Garden?

Here’s the wonderful news: if you spot Coenogonium missouriense in your garden, you should feel pretty good about your local ecosystem! Lichens are excellent indicators of air quality – they’re like nature’s canary in the coal mine. Their presence suggests that your air is relatively clean, as they’re quite sensitive to pollution.

While this lichen won’t attract butterflies or hummingbirds like flowering plants might, it does contribute to your garden’s biodiversity in subtle but important ways:

  • Provides microscopic habitat for tiny invertebrates
  • Contributes to nutrient cycling as it slowly breaks down rock and bark surfaces
  • Indicates healthy air quality in your garden space
  • Adds natural texture and visual interest to tree bark

How to Identify Coenogonium missouriense

Spotting this lichen takes a bit of detective work, but once you know what to look for, you’ll start noticing it everywhere! Here’s your identification checklist:

  • Color: Whitish-gray to pale gray, sometimes with a slightly greenish tint
  • Texture: Thin and crusty, growing tight against the bark surface
  • Location: Look on the bark of deciduous trees, particularly in areas with decent humidity
  • Size: Forms patches that can range from coin-sized to covering several square inches
  • Surface: May appear slightly powdery or granular up close

The best time to observe lichens is when they’re slightly damp – after morning dew or light rain – as this is when their colors are most vibrant and their textures most defined.

Can You Cultivate It?

Here’s where we need to set expectations: you can’t exactly plant Coenogonium missouriense like you would a tomato or a rose bush. Lichens are incredibly complex organisms that require very specific conditions to establish and thrive. They grow extremely slowly – we’re talking millimeters per year – and attempting to transplant them is rarely successful.

The good news? You don’t need to cultivate it! If your garden has the right conditions (decent air quality, appropriate humidity, and suitable host trees), this lichen may well establish itself naturally over time. Think of it as a bonus gift from nature rather than something you need to actively manage.

Creating Lichen-Friendly Conditions

While you can’t plant lichens directly, you can certainly encourage their presence in your garden:

  • Maintain mature trees with textured bark
  • Avoid using harsh chemicals or pesticides that might affect air quality
  • Keep some areas of your garden relatively undisturbed
  • Ensure good air circulation around trees
  • Consider the natural humidity levels – lichens prefer areas that aren’t bone dry

The Bottom Line

Coenogonium missouriense might not be the showiest addition to your garden, but it’s a fascinating example of the complex, interconnected web of life that exists right under our noses. If you’re lucky enough to have this native lichen growing in your space, take a moment to appreciate this small but significant piece of North American natural heritage.

Remember, gardening isn’t just about the plants we intentionally cultivate – it’s also about appreciating and protecting the wild communities that choose to make our spaces their home. And sometimes, those communities include remarkable partnerships like lichens that have been perfecting their collaborative lifestyle for millions of years.

So the next time you’re strolling through your garden, take a closer look at those tree trunks. You might just spot some Coenogonium missouriense quietly going about its ancient business of turning sunlight and air into living art.

Coenogonium Missouriense

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Ascomycota - Sac fungi

Subdivision
Class

Ascomycetes

Subclass
Order

Gyalectales

Family

Gyalectaceae Stizenb.

Genus

Coenogonium Ehrenb. - coenogonium lichen

Species

Coenogonium missouriense J. Davis

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