A tree hurts, too / [electronic resource] / Northeastern Forest Experiment Station, Forest Service, U.S. Department of Agriculture ; based on research by Alex L. Shigo ; illustrations by David M. Carroll ; produced in cooperation with Northeastern Area, State and Private Forestry, Upper Darby, Pennsylvania.. — New York : : Scribner,, [1975]. — 28 p. : : col. ill. ; 28 cm.