Boston Globe: Bill Keeton snowshoed into his scientific laboratory – a five-acre forest plot just off a blue-blazed hiking trail. On this recent snowy day, his forest lab looked utterly natural – a few wind-strewn trees lying under a canopy of beech, birch, and maple. But looks were deceiving; Keeton and others had logged and carefully shaped the wooded slope, using chainsaws and other machinery to emulate what happens in woodlands over centuries. Using Mother Nature as a blueprint, Keeton, …