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Photo attributed to Yinan Chen. This file has been released explicitly into the public domain by its author, using the Creative Commons Public Domain Dedication.
Photo attributed to Lynn Betts. This image is a work of the Natural Resources Conservation Service, part of the United States Department of Agriculture, taken or made as part of an employee's official duties. As a work of the U.S. federal government, the image is in the public domain in the United States.
