Unique curling patterns in paper birch bark ( Betula papyrifera) on a large tree trunk in Anchorage, Alaska in July.

- Image ID: BGGKTW
Unique curling patterns in paper birch bark ( Betula papyrifera) on a large tree trunk in Anchorage, Alaska in July.
Accent Alaska.com / Alamy Stock Photo
Image ID: BGGKTW