Page 3: Dichotomous Pairs 61 to 84
61. Twigs branching freely the first season, the branches surpassing the main axis in length. 62
61. Twigs generally not branching the first season (or if they do branch, then the branches do not surpass main axis in length). 63
62. Bundle-scars borne singularly (only one); twigs greenish, spicy/aromatic, mucilaginous when chewed.

Sassafras albidum,
Common Sassafras
62. Bundle-scars arranged in groups of 3, twigs not mucilaginous. Cornus alternifolia,
Pagoda Dogwood
63. Bundle-scars arranged singularly or in pairs (2); leaf-scars (except on young shoots) mainly densely clustered on short, stout, wart-like raised projections along branches.
64
63. Bundle-scars arranged in groups of 3 or more. 65
64. Bundle-scar single; leaf-scars minute (scattered leaf-scars also present on twigs) very numerous and strongly decurrent; twigs slender; fruit a cone, generally present. Larix sp.,
Larch
64. Bundle-scars in pairs (2); leaf-scars larger, scattered leaf-scars (if present) relatively far apart and not decurrent; twigs stouter; fruit a stone-fruit (generally absent, only found on female trees). Ginkgo biloba,
Ginkgo
65. Bundle-scars arranged 3 or more in a single curved line. 69
65. Bundle-scars found in groups of more than 3, variously grouped or scattered, but not in a single line. 66
66. Stipule-scars absent; terminal bud present. 68
66. Stipule-scars present; terminal bud present or absent. 67
67. 2-3 bud-scales visible; bundle-scars not projecting; terminal bud present or generally absent.

Castanea dentata,
American Chestnut
67. 4 or more bud-scales visible; bundle-scars projecting; terminal bud absent.

Morus sp.,
Mulberry

68. Buds large; twigs without resinous juice; fruit a nut; a tree. Carya sp.,
Hickory
68. Buds small; twigs with irritating resinous juice; fruit a small white drupe; a large shrub growing in wet areas. Rhus vernix,
Poison Sumac
69. Bundle-scars arranged in groups of 3. 74
69. Bundle-scars found in arrangements of 4 or more. 70
70. Terminal bud absent, but leaving a terminal scar on twig. 72
70. Terminal bud present. 71
71. Lateral buds mostly large; twig without resinous juice; fruit red, berry-like; a small tree. Sorbus americana,
American Mountainash
71. Lateral buds small; cut twig exuding watery, irritating resinous juice; fruit small, whitish drupes; a large shrub growing in wet areas. Rhus vernix,
Poison Sumac
72. Leaf-scars deeply V-shaped, almost entirely surrounding the buds. 73
72. Leaf-scars inversely triangular to heart-shaped, large, not more than half surrounding the bud; twigs stout; pith chocolate-brown. Ailanthus altissima,
Tree of Heaven
73. Pith yellowish-brown; twigs stout, exuding a milky juice when cut. Rhus sp.,
Sumac
73. Pith whitish; twigs slender, without milky juice. Cladrastis kentuckea,
American Yellowwood
74. Terminal buds on rapidly grown shoots absent, but leaving a terminal scar. 83
74. Terminal buds present. 75
75. Lateral buds flattened, appressed, about as broad as long. 76
75. Lateral buds not distinctly flattened and appressed, mostly longer than broad. 78
76. Terminal bud large, generally 12 mm. or more long; some of the lateral buds generally long, nearly equaling terminal bud; leaf-scars raised on dark red, polished ridges of the bark. Sorbus americana,
American Mountainash
76. Terminal bud smaller, generally under 8 mm. long; all lateral buds small; leaf-scars not located on specially-colored ridges of the bark. 77
77. Tree with bushy habit of growth; twigs with characteristic licorice-like taste, generally reddish-brown, more or less pale-woolly at lest toward apex; lateral buds blunt, more or less pale-woolly. Malus sylvestris,
Apple
77. Tree with upright habit of growth; twigs without characteristic taste, generally yellowish-green and generally smooth; lateral buds sharp-pointed, smooth or sometimes slightly downy. Pyrus communis,
Common Pear
78. Buds spherical or nearly so, seldom pointed; bud-scales thick, shiny; leaf-scars narrow; twigs more or less zigzag; branches generally thorny; fruit a small pome; small trees or shrubs. Crataegus sp.,
Hawthorn
78. Buds not spherical; bud-scales thinner. 79
79. Leaf-scars narrow crescent-shaped, several times as broad as high. 80
79. Leaf-scars semicircular to broadly crescent-shaped, seldom as much as 3 times as broad as high. 81
80. Buds long, narrow, elliptical, 3-4 times as long as wide.

Amelanchier canadensis,
Shadblow Serviceberry

80. Buds conical, stout. Pyrus communis,
Common Pear
81. Twigs densely speckled with very minute pale dots, brightly colored, generally green-yellow below and more or less reddish above and highly polished; buds generally densely downy at least toward the apex; collateral buds usually present. Prunus persica,
Peach
81. Twigs not densely speckled with minute dots; buds not densely down; collateral buds generally not present. 82
82. Twigs without bitter taste; branchlets generally becoming corky-ridged; bud-scales downy-margined; leaf-scars with conspicuous bundle-scars; fruit a spherical bur-like head generally present in winter. Liquidambar styraciflua,
American Sweetgum
82. Twigs with bitter taste often reminiscent of bitter almonds; branches without corky ridges; bud-scales not downy-margined; fruit a drupe. Prunus sp.,
Cherry or Plum
83. Buds spherical or nearly so; bud-scales thick, shining; twigs more or less zigzag, often thorny; fruit a small pome. Crataegus sp.,
Hawthorn
83. Buds not spherical, longer than broad. 84
84. Twigs generally gray-woolly toward apex; buds blunt, brown-hairy at tip; stipule-scars at the sides of leaf-scar. Cydonia oblonga,
Common Quince
84. Twigs smooth or downy but not woolly; buds pointed, generally smooth or somewhat downy; stipule-scars more or less behind leaf-scar. Prunus sp.,
Plum



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