About 18,000 species of lichens have been described. It sounds like you are describing foliose lichens. I hope this informtion is useful. The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.
Information listed is valid only for the state of Indiana.
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