Lichens are fascinating plants. They are composed of two different organisms – a fungal partner and a photosynthetic partner living in a symbiotic relationship.
The photosynthetic partner is either a green alga or a cyanobacterium (blue-green bacterium). Lichens get their nutrients from the food prepared by the photosynthetic partner, and the fungal partner provides the body and shape.
See pdf for more details.
The LSU AgCenter and the LSU College of Agriculture