Arkansas — David Stahle is a distinguished professor and director of the tree ring laboratory at the University of Arkansas, but you won’t always find him in the lab at Ozark Hall on the Razorback campus. You’re just as likely to find the world renowned dendrochronologist in the old growth forests of Oklahoma, the swamps of North Carolina or traversing the Great Plains as he searches for trees and takes coring samples from them. …For more than four decades this has been his chosen work, reconstructing climate and making chronologies, and Stahle has done it all over the world — in both the southwest and southeast regions of the U.S., in California, Africa, Nepal, and in Mexico partnering alongside a colleague in the Mexican Forest Service. …Stahle is working on book called “The Ancient Cross Timbers: A natural history of the old growth forest that bordered the Southern Plains”