Trees of the Northern United States Part 7

=L.= Fruit about in. in diameter, sweet, in drooping racemes 39. _Amelanchier._

=L.= Fruit either sour or much larger, and not in elongated racemes 37. _Pyrus._

=M.= Leaves harsh to the touch; somewhat oblique at base; quite distinctly two-ranked; large trees 74. _Ulmus._

=M.= Leaves decidedly oblique at base; margin wavy; small tree, usually a shrub 40. _Hamamelis._

=M.= Fruit berry-like, ending in a conspicuous spreading calyx; plant generally quite th.o.r.n.y 38. _Crataegus._

=M.= Leaves not regularly oblique at base; plant not th.o.r.n.y. (=N.=)

=N.= Leaves thin and light, not harsh to the touch; spray light; bark smooth, in two species somewhat rough on the trunk. (=Q.=)

=N.= Leaves thick; edge wavy, almost lobed; fruit an acorn.

88. _Quercus._

=N.= Leaves broad for the length, generally doubly serrate or wavy and serrate; shrubs, rarely tall enough for trees. (=P.=)

=N.= Not included in the above. (=O.=)

=O.= Leaves 3 or more times as long as wide, widest near the center; fruit a round, p.r.i.c.kly bur with 1-3 h.o.r.n.y-coated nuts 89. _Castanea._

=O.= Leaves widest near the sharply serrate tip, narrow and entire near the base; fruit small pods in terminal racemes; small tree or shrub 53. _Clethra._

=O.= Leaves widest near the base, usually small; bark scaling off like the b.u.t.tonwood; fruit axillary, solitary, small ( in.) roundish, dry drupes. A cultivated species, has rather large leaves, widest near the center 75. _Planera._

=P.= Fruit an open oval woody catkin or cone, remaining on the plant through the winter 84. _Alnus._

=P.= Fruit a rounded stony nut, in green leafy edged bracts; shrubs or small trees 85. _Corylus._

=Q.= Usually aromatic; bark dotted on the spray and with horizontal marks on the trunk, peeling off in thin, often papery layers 83. _Betula._

=Q.= Bark not peeling off in thin layers. (=R.=)

=R.= Leaf-buds long and slender; fruit a small p.r.i.c.kly bur with two triangular, h.o.r.n.y-coated nuts; large trees 90. _f.a.gus._

=R.= Fruit an elongated catkin with large leaf-like bracts; bark close, gray, on a grooved trunk 87. _Carpinus._

=R.= Fruit a hop-like catkin; bark brownish, finely furrowed 86. _Ostrya._

=S.= Plant more or less th.o.r.n.y; shrub or small tree; fruit rounded berries ending in persistent calyx-lobes 38. _Crataegus._

=S.= Plant not th.o.r.n.y. (=T.=)

=T.= Leaf deeply pinnatifid, usually with the basal lobes completely separated; cultivated 37. _Pyrus._

=T.= End of leaf as though cut off; sides with one large lobe; margin entire; large tree 2. _Liriodendron._

=T.= Lower leaves three-lobed, heart-shaped at base, upper merely ovate, margin entire; small tree or shrub 66. _Clerodendron._

=T.= Not as above; leaves usually many-lobed. (=U.=)

=U.= Leaves thin; bark of trunk peeling off in thin horizontal strips 83. _Betula._

=U.= Leaves thin; leaf-buds long, slender, sharp-pointed; bark smooth, not peeling; cultivated 90. _f.a.gus._

=U.= Leaves thickish; bark roughish; fruit an oval woody cone, remaining on through the year 84. _Alnus._

=U.= Leaves thick; fruit an acorn 88. _Quercus._

=V.= Leaves evergreen, small, 2-3 in. long, thick, with revolute margins; fruit an acorn 88. _Quercus._

=V.= Leaves evergreen, oval to lance-oval, usually large; small trees, almost shrubs. (=d.=) page 56.

=V.= Leaves deciduous (some are evergreen in the Southern States). (=W.=)

=W.= Plant more or less spiny. (=c.=)

=W.= Plant not at all spiny. (=X.=)

=X.= Leaf-blade thin, long, pointed, with curved parallel veins or ribs 45. _Cornus._

=X.= Leaf-blade thin, circular or broadly oval in outline, with blunt, almost rounded apex; veins not regularly parallel 27. _Rhus._

=X.= Leaf quite elongated, 5 or more times as long as wide.

(=b.=)

=X.= Leaves with none of the above peculiarities. (=Y.=)

=Y.= Deciduous bud-scales (stipules), leaving a scar or mark completely around the stem at the base of the leaves. 1. _Magnolia._

=Y.= Leaves covered on one or both sides with silvery scales 71. _Elaeagnus._

=Y.= No such ring around the stem, or silvery scales on the leaves. (=Z.=)

=Z.= Leaves distinctly straight-veined, thin 90. _f.a.gus._

=Z.= Leaves thick, obtuse; fruit an acorn 88. _Quercus._

=Z.= Leaves 6 in. or more long; crushed leaves with a rank, fetid odor 5. _Asimina._

=Z.= Leaves 3-5 in. long; twigs and leaves very spicy; shrub rather than tree 70. _Lindera._

=Z.= Leaves about 2 in. long, oval, on twigs which have ridges extending down from the sides of the leafstalk; small tree, almost a shrub, with beautiful flowers 43. _Lagerstroemia._

=Z.= Leaves not as above. (=a.=)

=a.= Fruit a large (-1 in.) rounded pulpy berry with a heavy calyx at the base 55. _Diospyros._