Contact: Mari N. Jensen
mnjensen@email.arizona.edu
520-626-9635
University of Arizona

Paul R. Sheppard, University of Arizona

Caption: Paul Sheppard of the University of Arizona's Laboratory of Tree-Ring Research seated at the microscope he uses to count the annual rings in tree cores. He is holding one of the pencil-thin cores mounted on a block of wood for ease of handling.

Credit: Laboratory of Tree-Ring Research, the University of Arizona.

Usage Restrictions: Photo must be used only in connection with a story about the research described in this release. Photo credit must be given as: Laboratory of Tree-Ring Research, The University of Arizona.

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