Image credit: Denise Applewhite, Office of Communications

There are more clues to the past lurking beneath a tree's bark than just rings to count.

Hunting down that evidence starts with a simple boring device, as demonstrated recently along Washington Road on the Princeton University campus as 15 graduate students, researchers and junior faculty, guided by instructors, extracted a long, thin piece of a conifer's core during a workshop on dendroclimatology — the science of determining past climates from trees.