A. Leaves twice compound: Gymnocladus, Gleditsia
A. Leaves once compound: go to B

. . .B. Leaves opposite: go to C

. . . . . .C. Leaves palmate: Aesculus
. . . . . .C. Leaves pinnate: Acer negundo, Fraxinus
. . .B. Leaves alternate: go to D

. . . . . .D. 3 leaflets: Ptelea
. . . . . .D. 5 or 7 leaflets: Carya
. . . . . .D. 9 or more leaflets: go to E

. . . . . . . . .E. leaflet margins entire: Gleditia, Cladrastis, Ailanthus, Robinia
. . . . . . . . .E. leaflets toothed: Gleditia, Ailanthus, Rhus, Juglans, Sorbus

A. leaves whorled in 3's: Catalpa or Paulownia
A. leaves simple: go to F

. . .F. leaves opposite: go to G

. . . . . .G. leaves palmatedly lobed: Acer
. . . . . .G. leaves with entire margin: go to H

. . . . . . . . .H. Bark blocky, fruit little scarlet cluster of berries: Cornus florida
. . . . . . . . .H. Bark scaly, fruit a pink blobbo: Cornus kousa
. . .F. Alternate leaves: go to I

. . . . . .I. Leaves with 4 lobes: Liriodendron
. . . . . .I. Leaves palmately lobed: Platanus
. . . . . .I. Leaves pinnately lobed: Quercus
. . . . . .I. Leaves not lobed: go to J

. . . . . . . . .J. Leaf margin entire: Fagus sylvatica, Magnolia
. . . . . . . . .J. Leaf margin toothed: go to K

. . . . . . . . . . . .K. Bark papery and white: Betula papyrifera or populifolia
. . . . . . . . . . . .K. Bark smooth and grey: Fagus grandifolia
. . . . . . . . . . . .K. Otherwise: Broussonetia, Populus, Prunus, Morus, Crataegus, Pyrus, Ulmus, Celtis, Eleagnus