Tree Identification Field Guide. Our il.rated, step-by-step process makes it easy to identify a tree simply by the kinds of leaves it produces. Begin identifying .What is the shape of the leaf? Is it a single leaf like these ones? sweetgum leaf e.g. birch leaf leaf withebeam spanish chestnut single leaf identification ."CAUTION! --- Both Poison Sumac and Poison Ivy occur in Ohio. Read about them; know what they look like before you touch unknown trees, shrubs or vines!"..