Parmotrema Perlatum Lichen is a leafy lichen with a grey-green thallus that is loosely attached to tree branches, cement walls or rocks, it grows all over the Pacific Northwest.
A single specimen can grow to about 15 cm in size. The lobes that make up the thallus are up to 15 mm in wide. The lobes have wavy edges and are raised up from the surface where it grows and contains soralia. The underside is dark and quite black towards the center and the edge of the lobes is an earthy brown in color. The edge itself is black, thus its common name of black-edged leaf lichen.
This lichen grows best in old-growth forests, it grows on trees usually along the branches, it is capable of absorbing nitrogen from the air and when the lichen falls to the forest floor, it releases the nitrogen into the soil, thus food for its host trees. It is a forest healer, usually only found in old-growth forests.