Common Shield Lichen Parmelia sulcata

Identification
This lichen has gray lobes with white ridges.

Location
Common statewide

Size
Two to six inch patches

Diet
It absorbs nutrients from air and rainfall.

Habitat
It occurs in forests and suburban trees.

Activity Period
Year round

Behavior
It forms leafy rosettes on bark and rock. It remains visible year round.

Lifecycle
Reproduction occurs through soredia.

Population
The population is stable statewide.

History
It has long been widespread in Ohio.

Human Interactions
It is tolerant of moderate pollution.

Facts
Its ridges resemble cracked asphalt.

Sources
ODNR academic sources

Airborne nutrients moisture | Tree bark rocks logs | Statewide