LICHEN

Growth on rocks

• Alga-fungus combination

• Alga-fungus symbiosis

• Beard moss, for one

• Fungus + alga

• Fungus-alga combo

• Fungus-alga composite

• Fungus-alga union

• Fungus-algae alliance

• Fungus/alga symbiosis

• Growth on rock walls

• Growth on trees and rocks

• Iceland moss

• It may grow on rocks

• Mossy growth

• Oakmoss, e.g.

• Rock fungus

• Rock growth

• Rock plant

• Source of litmus

• Symbiotic growth

• Symbiotic growth on trees and rocks

• Tree growth

• Tree-trunk cover, perhaps

• Woodsy growth

• Any thallophytic plant of the division Lichenes

• Occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc.