Crusty Navel Lichen: A Fascinating Natural Indicator in Your Landscape
Have you ever noticed those crusty, coin-shaped growths on rocks or tree bark and wondered what they are? Meet the crusty navel lichen (Umbilicaria crustulosa), a fascinating organism that’s neither plant nor animal, but something wonderfully unique that might already be calling your property home.
What Exactly Is Crusty Navel Lichen?
Despite its name suggesting it’s a plant, crusty navel lichen is actually a lichen – a remarkable partnership between fungi and algae working together in perfect harmony. This collaboration creates those distinctive crusty, circular patches you might spot dotting rocks, boulders, or occasionally tree bark around your landscape.
The navel part of its name comes from its unique attachment method – unlike many lichens that spread across surfaces, crusty navel lichen attaches at a single central point, much like a belly button, giving it that characteristic umbilical appearance.
Where You’ll Find This Native Beauty
Crusty navel lichen is native to North America and can be found across a wide range of temperate and boreal regions. It’s particularly common in areas with clean air and naturally occurs on exposed rock surfaces, from mountain slopes to forest floors.
Identifying Crusty Navel Lichen
Spotting crusty navel lichen is easier than you might think once you know what to look for:
- Circular to irregular crusty patches, typically 2-6 inches across
- Gray to brown coloration, sometimes with darker edges
- Thick, leathery texture that feels rough to the touch
- Single point of attachment at the center (the navel)
- Often found on exposed rock surfaces, especially granite and other hard stones
Is It Beneficial to Your Garden?
While you can’t exactly plant crusty navel lichen like you would a flower or shrub, having it appear naturally on your property is actually a wonderful sign! Here’s why you should appreciate this unique organism:
- Air quality indicator: Lichens are extremely sensitive to air pollution, so their presence indicates clean, healthy air around your home
- Natural character: They add authentic, wild beauty to rock gardens, stone walls, and natural landscapes
- Low maintenance: They require absolutely no care from you – they’re completely self-sufficient
- Ecosystem contribution: They slowly break down rock surfaces, contributing to soil formation over time
Creating Lichen-Friendly Spaces
While you can’t cultivate crusty navel lichen like traditional garden plants, you can create conditions that encourage natural lichen growth:
- Incorporate natural stone features like rock walls, boulders, or stone pathways
- Avoid using chemical treatments near stone surfaces
- Maintain good air quality around your property
- Be patient – lichens grow very slowly, often taking years to establish
A Word of Caution
If you’re fortunate enough to have crusty navel lichen growing naturally on your property, resist the urge to clean it off rocks or disturb it. These slow-growing organisms can take decades to reach maturity, and once removed, they may never return to that spot.
The Bottom Line
Crusty navel lichen isn’t something you’ll find at your local garden center, but discovering it growing naturally on your property is like finding a hidden treasure. It’s a sign that your landscape supports healthy, diverse life forms and maintains the kind of clean environment that many areas have lost.
Rather than trying to cultivate it, simply appreciate this remarkable organism for what it is – a living testament to the intricate partnerships that make our natural world so fascinating. Next time you’re walking around your property, take a moment to look for these crusty, navel-like patches on your rocks. You might be surprised by what you discover!
