Bolander’s Map Lichen: Nature’s Living Art on Your Garden Rocks
If you’ve ever noticed what looks like a crusty, map-like design sprawling across rocks in your garden, you might have encountered Bolander’s map lichen (Rhizocarpon bolanderi). This fascinating organism isn’t actually a plant at all – it’s a lichen, which means it’s a unique partnership between fungi and algae working together to create something pretty amazing.
What Exactly Is Bolander’s Map Lichen?
Bolander’s map lichen is a crustose lichen native to North America, particularly found throughout western regions including California and Oregon. Unlike the plants we typically think about for our gardens, lichens are composite organisms that form when fungi and algae decide to be roommates. The fungus provides structure and protection, while the algae produce food through photosynthesis – it’s nature’s perfect partnership!
Spotting This Natural Wonder
Identifying Bolander’s map lichen is like reading nature’s own topographical map. Here’s what to look for:
- Crusty, flat patches that seem glued to rock surfaces
- Distinctive black lines that create a map-like or puzzle-piece pattern
- Grayish to yellowish-green coloration
- Preference for exposed rock faces and boulders
- Slow-growing patches that can persist for decades
Is It Good for Your Garden?
While you can’t exactly plant Bolander’s map lichen like you would a tomato, having it show up naturally in your garden is actually a wonderful sign! Here’s why:
- Air quality indicator: Lichens are sensitive to air pollution, so their presence suggests your garden enjoys clean air
- Natural character: They add an authentic, wild look to rock gardens and natural landscapes
- Low maintenance: Once established, they require absolutely no care from you
- Erosion prevention: They help stabilize rock surfaces over time
Creating Lichen-Friendly Conditions
You can’t plant lichens like traditional garden plants, but you can create conditions that might encourage them to appear naturally:
- Leave some bare rock surfaces exposed in your garden
- Avoid using chemical treatments near rocky areas
- Maintain good air quality around your property
- Be patient – lichens grow incredibly slowly, sometimes less than a millimeter per year
A Word of Caution
If you’re lucky enough to have Bolander’s map lichen in your garden, treat it with respect. These organisms grow extremely slowly and can take decades to reach maturity. Avoid scraping or disturbing rock surfaces where lichens are growing, and never attempt to transplant them – they simply won’t survive the process.
The Bottom Line
Bolander’s map lichen isn’t something you can add to your shopping cart at the garden center, but it’s a fascinating indicator of a healthy, natural environment. If you spot these living maps decorating the rocks in your garden, consider yourself lucky – you’re witnessing one of nature’s most successful partnerships in action. Just sit back, admire their slow-motion artistry, and enjoy knowing that your garden air is clean enough to support these remarkable organisms.
