British Soldier Lichen- Sue Wetmore
Pixie Cup Lichen
Rosette Lichen
Pixie Cup Cluster
Maybe you’d looked up at our trees and wondered — what is that green stuff growing on the bark? Lichens are often found growing on older trees, as both grow very slowly. The British Soldier lichen is often found on old stumps, and the rosette can be found on branches. Pixie Cups are often found growing up in moss, on rocks, stumps or fallen logs. All of these can be found in Brandon, Pittsford, Middlebury — just don’t forget to look down while you’re in the woods.
Cool lichen facts:
Lichens are neither fungi nor plants — they are both! The outer skin and internal structure of a lichen is made of strands of fungal hyphae. Interspersed among the strands inside the lichen are individual cells of algae. This kind of interaction between two different organisms is called symbiosis or mutualism.
The fungus may be getting the better end of the deal. The fungal partner in the lichen symbiosis provides a home for its algal associate to live that is relatively safe from predators and somewhat climate-controlled (the algae get exposed to sunlight, but are protected from drying out). Being photosynthetic, the algae provide food for themselves and the fungus. The algal partner can usually live outside of the lichen in streams, ponds, or wet soil. The fungal partner, however, has become dependent on the algae for its food and cannot live off of decaying organisms like other fungi. Some scientists think the relationship between lichenized fungi and algae is actually a controlled form of parasitism.
Lichens typically consist of one species of fungus and 1-2 species of algae. The algal partner may be a species of green algae (Chlorophyta) or a cyanobacterium (Cyanophyta, formerly called blue-green algae). Lichens are named for the fungus species rather than the type of algae in the partnership, since the fungus is the more conspicuous member. Some lichens contain additional microbes, and the entire structure might be better considered its own little ecosystem.
Additional photos by Carey Bunker.
