Tree trunk covered in red lichen, an indicator of good air quality.

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Size: 3541px × 2365px
Photo credit: © Lucia Tieko / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: air, algae, biology, botany, ecology, ecosystem, environment, fungi, good, lichen, lichens, microorganisms, natural, nature, organisms, quality, red, tree, trunk