03/27/2026
🌿 Let’s talk lichen, because they completely changed how I see nature.
For the longest time I walked right past them. Crusty patches on rocks, leafy rosettes on fallen logs. I thought they were moss. Turns out lichen aren’t really any one thing at all.
Lichen are a partnership. A fungus and a photosynthetic partner (usually algae, sometimes cyanobacteria) living so tightly together they become something neither could be alone. The fungus provides structure. The algae make food and share it. Two organisms, one life form.
That’s why lichen grow where almost nothing else can; bare rock, arctic tundra, desert surfaces. Some are thousands of years old. They’re literally breaking down stone into soil, making the ground we walk on over centuries.
There are three forms you’ll start spotting once you know what to look for 👇🏿
🪨 Crustose — flat & crusty, almost painted onto the surface
🍃 Foliose — leafy and lobed, like tiny lettuce on bark or rock
🌿 Fruticose — shrubby or hanging, like Old Man’s Beard (Usnea sp.)
Slow down on your next hike and look at the rocks and bark around you. The lichen have been there longer than the trees. 🍄🌱