Lichens don't harm plants

26th July 2021

Lichens like this beautiful example may live on old wood in trees but they aren't parasites - they are a symbiotic (possibly oakmoss?) partnership between a fungus and an alga (or a cyanobacterium) living on, not off the tree: the fungus helps provide structure, the algae can photosynthesise to create food. This one is possibly oakmoss (Evernia prunastri) or dotted ribbon lichen (Ramalina fastigiata)?