After swimming in the lake and a few rounds of fetch at the Ithaca Dog Park on a beautiful Sunday afternoon, Sophie, an eight-year-old plump English lab, shyly deposited a small pile of doo next to a bush. Her owner, Prof. Leon Kochian, plant biology, picked up the poop, dumped it into a free black bag obtained at one of the five bag dispensers in the Park and disposed of the evidence in a sky-blue bin labeled “compost” located at the Park’s entrance.