Chapter IV: Part 4

LEAVES.--Alternate, simple, 2-5 inches long, about one-half as broad; oval or oblong to oblong-lanceolate; finely serrate, with teeth incurved; subcoriaceous; dark green and very lustrous above, paler beneath, glabrous both sides; petioles short, slender, usually bearing 2 red glands near the blade.

FLOWERS.--May-June, when the leaves are half grown; perfect; 1/4 inch across; borne on slender pedicels in many-flowered, loose racemes 4-5 inches long; calyx cup-shaped, 5-lobed; petals 5, white; stamens 15-20; stigma thick, club-shaped.

FRUIT.--August-September; a globular drupe, 1/3-1/2 inch in diameter, nearly black, with dark purple, juicy flesh; slightly bitter, edible.

WINTER-BUDS.--Terminal bud about 1/4 inch long, ovoid, blunt to acute; scales keeled on the back, apiculate, light brown.

BARK.--Twigs and branches red to red-brown; young trunks dark red-brown, smooth; blackish on old trunks and rough, broken into thick, irregular plates; bitter, aromatic.

WOOD.--Light, rather hard, strong, close- and straight-grained, light brown or red, with thin, yellow sapwood.

DISTRIBUTION.--Frequent in the southern half of the Lower Peninsula, rare in the northern half and the Upper Peninsula.

HABITAT.--Prefers a rich, moist soil, but grows well on dry, gravelly or sandy soils.

NOTES.--Grows very rapidly in youth.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1.
4. Margin of leaf, enlarged.
5. Flowering branchlet, × 1/2.
6. Vertical section of flower, enlarged.
7. Fruit, × 1/2.]

+ROSACEAE+

+Choke Cherry+

_Prunus virginiana L._ [_Padus virginiana (L.) Roemer_]

HABIT.--Usually a large shrub, but sometimes a small tree 15-25 feet high, with a crooked, often leaning trunk 5-6 inches in diameter; forming a spreading, somewhat rounded crown.

LEAVES.--Alternate, simple, 2-4 inches long, one-half as broad; obovate to oblong-obovate or oval, abruptly acuminate at the apex; finely and sharply serrate; dull dark green above, paler beneath, glabrous both sides; petioles short, slender, glandular at the apex.

FLOWERS.--May, when the leaves are half grown; perfect; about 1/2 inch across; borne on short, slender pedicels in many-flowered racemes 3-6 inches long; calyx cup-shaped, 5-lobed; petals 5, white; stamens 15-20; stigma broad, on a short style.

FRUIT.--July-August; a globular drupe, 1/4-1/2 inch in diameter, usually bright red, often yellow to almost black, with dark red flesh; astringent, but edible.

WINTER-BUDS.--Terminal bud 1/4-1/2 inch long, conical, acute; scales rounded at the apex, light brown, smooth.

BARK.--Twigs at first light brown or greenish, becoming red-brown, finally dark brown; thin, dark brown on the trunk, slightly fissured.

WOOD.--Heavy, hard, close-grained, weak, light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Common throughout the entire state.

HABITAT.--Prefers a deep, rich, moist loam, but is common on less favorable sites.

NOTES.--The most widely distributed tree of North America, extending from the arctic circle to Mexico, from the Rocky Mountains to the Atlantic Ocean.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1.
4. Margin of leaf, enlarged.
5. Flowering branchlet, × 1/2.
6. Flower, enlarged.
7. Fruit, × 1.]

+ROSACEAE+

+Wild Red Cherry. Pin Cherry+

_Prunus pennsylvanica L. f._

HABIT.--A slender tree, seldom over 30 feet high, with a trunk diameter of 8-10 inches; crown rather open, narrow, rounded, with slender, regular branches.

LEAVES.--Alternate, simple, 3-5 inches long, 3/4-1-1/4 inches broad; oblong-lanceolate; finely and sharply serrate; bright green and shining above, paler beneath; petioles slender, 1/2-1 inch long, glandular near the blade.

FLOWERS.--May-June, with the leaves; perfect; about 1/2 inch across, borne on slender pedicels in 4-5-flowered umbels, generally clustered, 2-3 together; calyx 5-cleft, campanulate; petals 5, white, 1/4 inch long; stamens 15-20.

FRUIT.--July-August; a globular drupe, 1/4 inch in diameter, light red, with thick skin and sour flesh.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid, rather blunt, brownish, smooth.

BARK.--Twigs at first lustrous, red, marked by orange colored lenticels, becoming brownish; red-brown and thin on the trunk, peeling off horizontally into broad, papery plates; bitter, aromatic.

WOOD.--Light, soft, close-grained, light brown, with thin, yellow sapwood.

DISTRIBUTION.--Throughout the northern portion of the state, extending southward to Ionia County.

HABITAT.--Abundant on sand-lands; roadsides; burned-over lands; clearings; hillsides.

NOTES.--Rapid of growth. Short-lived.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1/2.
4. Flowering branchlet, × 1/2.
5. Vertical section of flower, × 1.
6. Fruiting branchlet, × 1/2.]

+ROSACEAE+

+Canada Plum. Red Plum+

_Prunus nigra Ait._ [_Prunus americana, v. nigra Waugh_]

HABIT.--A small tree 20-25 feet high and 5-8 inches in trunk diameter; usually divides 5-6 feet from the ground into a number of stout, upright branches, forming a narrow, rigid crown.

LEAVES.--Alternate, simple, 3-5 inches long and one-half as broad; oblong-ovate to obovate, abruptly acuminate at the apex; doubly crenate-serrate; thick and firm; glabrous, light green above, paler beneath; petioles short, stout, bearing 2 large red glands near the blade.

FLOWERS.--May, before the leaves; perfect; slightly fragrant; about 1 inch across; borne on slender, glabrous, red pedicels in 2-3-flowered umbels; calyx 5-lobed, dark red; petals 5, white; stamens 15-20, with purple anthers; ovary 1-celled; style 1; stigma 1.

FRUIT.--August-September; a fleshy drupe, about 1 inch long, oblong-ovoid, with a tough, thick, orange-red skin nearly free from bloom, and yellow flesh adherent to the flat stone. Eaten raw or cooked.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8-1/4 inch long, ovate, acute, chestnut-brown.

BARK.--Twigs green, marked by numerous pale excrescences, later dark brown; thin, gray-brown and smooth on young trunks, but soon splitting off in large, thick plates, exposing the darker inner bark.

WOOD.--Heavy, hard, strong, close-grained, light red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Upper Peninsula and the Lower Peninsula north of Lansing.

HABITAT.--Prefers rich, alluvial soil along streams.

NOTES.--Suckers freely, forming low, broad thickets.

1. Winter twig, × 1.
2. Leaf, × 1/4.
3. Leaflet, × 1/2.
4. Vertical section of staminate flower, enlarged.
5. Vertical section of pistillate flower, enlarged.
6. Fruit, × 1/4.]

+LEGUMINOSAE+

+Coffeetree. Kentucky Coffeetree+

_Gymnocladus dioica (L.) Koch_ [_Gymnocladus canadensis Lam._]

HABIT.--A slender tree 50-75 feet high, with a trunk diameter of 2-3 feet; divides near the ground into several stems which spread slightly to form a narrow, pyramidal crown; branchlets stout, clumsy, blunt, with conspicuous leaf-scars.

LEAVES.--Alternate, bipinnately compound, 1-3 feet long. Leaflets 40 or more, 2-2-1/2 inches long and one-half as broad; short-stalked; ovate, acute; entire; thin and firm; dark green above, pale yellow-green and glabrous beneath. Petioles stout, terete, glabrous. Appear late in spring.

FLOWERS.--June, after the leaves; dioecious; greenish white; the staminate short-stalked, in racemose corymbs 3-4 inches long; the pistillate long-stalked, in racemes 10-12 inches long; calyx tubular, hairy; petals 5, keeled, nearly white; stamens 10; ovary hairy.

FRUIT.--Ripens in autumn, but remains closed until late in winter; short-stalked, red-brown legumes 6-10 inches long, 1-1/2-2 inches wide, containing 6-9 large, flat seeds.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, depressed, 2 in the axil of each leaf, bronze-brown, silky-pubescent.

BARK.--Twigs coated with short, dense, reddish pubescence, becoming light brown; thick, deeply fissured and scaly on the trunk, dark gray.

WOOD.--Heavy, somewhat soft, strong, coarse-grained, very durable in contact with the soil, light red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Southern Michigan as far north as the Grand River. Infrequent.

HABITAT.--Prefers bottom-lands and rich soil.

NOTES.--The seeds in early days were used as a substitute for coffee.

1. Winter twig, × 1.
2. Vertical section through lateral buds, enlarged.
3. Leaf, × 1/4.
4. Leaflet, × 1.
5. Staminate flowering branchlet, × 1/2.
6. Staminate flower, enlarged.
7. Pistillate flowering branchlet, × 1/2.
8. Pistillate flower, enlarged.
9. Fruit, × 1/3.
10. Spine from trunk, × 1/2.]

+LEGUMINOSAE+

+Honey Locust. Three-thorned Acacia+

_Gleditsia triacanthos L._

HABIT.--A tree usually 50-75 feet high, with a trunk diameter of 2-3 feet; dividing near the ground into several large, upright branches which divide again into long, slender, horizontal branchlets; both trunk and large branches armed with stout, rigid, simple or branched spines.

LEAVES.--Alternate, pinnately or bipinnately compound, 7-12 inches long. Leaflets 18 or more, 3/4-1-1/2 inches long, one-third as broad; lanceolate-oblong; remotely crenulate-serrate; thin; lustrous, dark green above, dull yellow-green beneath. Petioles and rachises pubescent.

FLOWERS.--May-June, when the leaves are nearly full grown; polygamo-dioecious; the staminate in short, many-flowered, pubescent racemes; the pistillate in slender, few-flowered racemes; on shoots of the preceding season; calyx campanulate, hairy 3-5-lobed; petals 3-5, greenish; stamens 3-10; ovary 1-celled, woolly.

FRUIT.--Autumn, falling in early winter; flat, pendent, twisted, brown legumes, 12-18 inches long, short-stalked in short racemes; seeds 12-14, oval, flattened.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, 3 or more superposed, glabrous, brownish.

BARK.--Twigs lustrous, red-brown, becoming gray-brown; thick on the trunk, iron-gray to blackish and deeply fissured into long, narrow ridges roughened by small scales.

WOOD.--Hard, strong, coarse-grained, durable in contact with the ground, red-brown, with thin, pale sapwood.

DISTRIBUTION.--Indigenous to the extreme southern portion of the state, but is planted as far north as Bay City.

HABITAT.--Prefers deep, rich loam, but grows on a variety of soils.

NOTES.--Grows rapidly and is long-lived and free from disease. Easily transplanted. The leaves appear late in spring and fall early in autumn. The stiff spines and long pods which litter the ground make the tree unsuitable for street or ornamental use.

1. Winter twig, × 1.
2. Portion of twig, front view, enlarged.
3. Portion of twig, side view, enlarged.
4. Leaf, × 1/2.
5. Flowering branchlet, × 1.
6. Vertical section of flower, enlarged.
7. Fruit, × 1/2.]

+LEGUMINOSAE+

+Redbud. Judas-tree+

_Cercis canadensis L._

HABIT.--A small tree 20-30 feet high, with a trunk diameter of 10-15 inches; divided near the ground into stout, straggling branches to form a broad, flat crown.

LEAVES.--Alternate, simple, 3-5 inches long and broad; heart-shaped or rounded; entire; thick; glabrous, dark green above, paler beneath, turning bright yellow in autumn; petioles slender, terete, enlarged at the base.

FLOWERS.--April-May, before or with the leaves; perfect; 1/2 inch long; borne on short, jointed pedicels in fascicles of 4-8; calyx campanulate, 5-toothed, dark red; petals 5, rose color; stamens 10, in 2 rows.

FRUIT.--June-July, remaining on the tree until early winter; a short-stalked legume 2-1/2-3 inches long, pointed at both ends, rose color; seeds 10-12, brownish, 1/4 inch long.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/8 inch long, obtuse, somewhat flattened and appressed, brownish.

BARK.--Twigs lustrous, brown, becoming dark or grayish brown; red-brown, deeply fissured, with a scaly surface on old trunks.

WOOD.--Heavy, hard, coarse-grained, weak, dark red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Valleys of the Grand and Raisin Rivers and southward.

HABITAT.--Prefers the borders of streams and rich bottom-lands, often in the shade of other trees.

NOTES.--A rapid grower. Hardy within its range. Can be transplanted with success only when very young. Plants begin to produce flowers freely when 4-5 years old. Much used in landscape gardening.

1. Winter twig, × 1.
2. Vertical section through lateral buds, enlarged.
3. Leaf, × 1/2.
4. Raceme of flowers, × 1/2.
5. Flower, with part of corolla removed, enlarged.
6. Fruit, × 1/2.]

+LEGUMINOSAE+

+Locust. Black Locust+

_Robinia pseudo-acacia L._

HABIT.--A tree 50-75 feet high, with a trunk diameter of 2-3 feet; forming a narrow, oblong crown of irregular, more or less contorted branches.

LEAVES.--Alternate, compound, 8-14 inches long. Leaflets 7-21, short-petiolate, 1-2 inches long, about one-half as broad; ovate to oblong-oval; entire; very thin; dull dark green above, paler beneath, glabrous both sides. Petioles slender, pubescent.

FLOWERS.--May-June, after the leaves; perfect; showy and abundant; very fragrant; borne on slender pedicels in loose, drooping racemes 4-5 inches long; about 1 inch long; calyx short, bell-shaped, 5-lobed, hairy; corolla papilionaceous, white, 5-petaled; stamens 10.

FRUIT.--Late autumn, but persistent on the tree through the winter; a smooth, dark brown, flat pod 3-4 inches long, containing 4-8 small, flattish, brown seeds.

WINTER-BUDS.--Terminal bud absent; lateral buds minute, 3-4 superposed, partially sunken within the leaf-scar, rusty-hairy.

BARK.--Twigs smooth, green, more or less rough-dotted at first, becoming red-brown and armed with prickles; dark red-brown and thick on old trunks, deeply furrowed into firm, sinuous ridges.

WOOD.--Heavy, very strong and hard, close-grained, very durable in contact with the soil, brown, with very thin, pale yellow sapwood.

NOTES.--Native to the Appalachian Mountains, but much planted in Michigan for ornamental and economic uses. Very rapid of growth in youth. Short-lived. Seriously attacked by borers. Spreads by underground shoots.

1. Winter twig, × 1.
2. Leaf, × 1/8.
3. Leaflet, × 1/2.
4. Staminate inflorescence, × 1/4.
5. Staminate flower, enlarged.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+SIMARUBACEAE+

+Ailanthus. Tree of Heaven+

_Ailanthus glandulosa Desf._

HABIT.--A handsome, rapid-growing, short-lived tree, attaining a height of 50-70 feet and a trunk diameter of 2-4 feet, with a spreading, rather loose and open crown and a coarse, blunt spray.

LEAVES.--Alternate, pinnately compound, 1-3 feet long. Leaflets 11-41 in number, 2-6 inches long and about one-third as broad; ovate-lanceolate; entire with the exception of two or more coarse, glandular teeth at the base; glabrous, dark green above, paler beneath, turning a clear yellow in autumn or falling without change; ill-scented. Petioles smooth, terete, swollen at the base.

FLOWERS.--June, when the leaves are full grown; polygamo-dioecious; small, yellow-green, borne in upright panicles 6-12 inches or more in length; calyx 5-lobed; petals 5, greenish, hairy; stamens 10. Staminate flowers ill-scented, pistillate almost free from odor.

FRUIT.--October; 1-celled, 1-seeded samaras, spirally twisted, reddish or yellow-green, borne in crowded clusters.

WINTER-BUDS.--Terminal bud absent; lateral buds about 1/8 inch long, subglobose, brownish, downy.

BARK.--Twigs yellowish to red-brown, velvety-downy; thin, grayish and shallowly fissured on old trunks.

WOOD.--Soft, weak, of coarse and open grain, pale yellow, satiny, with thick, lighter colored sapwood.

NOTES.--A native of China, but naturalized in the United States and planted frequently in southern Michigan as a foliage tree. Only the pistillate trees should be planted, as these are almost free from the objectionable odor of the staminate trees. The smoke and dust of our large cities have little effect on the foliage, and the trees are perfectly hardy in the southern part of the state.

+SUMMER KEY TO THE SPECIES OF ACER+

a. Leaves simple; twigs usually without whitish bloom.

b. Leaf-sinuses acute at the base.

c. Leaf-lobes long and narrow, the sides of the terminal lobe
diverging; leaves silvery white beneath; twigs rank-smelling
when broken. _A. saccharinum_, p. 185.

cc. Leaf-lobes short and broad, the sides of the terminal lobe
converging; leaves not conspicuously white beneath; twigs not
rank-smelling when broken.

d. Leaves 2-4 inches broad, thin, not pentagonally 5-lobed;
wings of fruit 3/4-1 inch long.

e. Leaves distinctly white-downy beneath; twigs
appressed-hairy, at least near the tip; fruit hanging in
pendulous racemes, persistent on the tree until autumn; seed
portion with pit-like depression on one side; usually a shrub
or bushy tree. _A. spicatum_, p. 179.

ee. Leaves not distinctly white-downy beneath; twigs glabrous;
fruit hanging in clusters, falling in early summer; seed
portion without pit-like depression on one side; medium-sized
tree. _A. rubrum_, p. 187.

dd. Leaves 4-7 inches broad, thick, pentagonally 5-lobed; wings
of fruit 1-1/2 inches long. _A. pseudo-platanus_, p. 191.

bb. Leaf-sinuses rounded at the base.

c. Lower sides of leaves and petioles distinctly downy, the
lobes undulate or entire; leaves very thick, drooping at the
sides. _A. saccharum nigrum_, p. 183.

cc. Lower sides of leaves and petioles essentially glabrous,
the lobes serrate; leaves not thick, not drooping at the sides.

d. Leaves coarsely and sparsely toothed or notched; bark not
longitudinally white-striped; large trees.

e. Twigs coarse; petioles exuding a milky juice when cut; wings
of fruit diverging by nearly 180°; bark of the trunk closely
fissured, not scaly. _A. platanoides_, p. 189.

ee. Twigs slender; petioles not exuding a milky juice when cut;
wings of fruit diverging only slightly; bark of the trunk
deeply furrowed, often cleaving in long, thick plates. _A.
saccharum_, p. 181.

dd. Leaves finely and abundantly toothed; bark longitudinally
white-striped; a bushy tree or shrub.

aa. Leaves compound; twigs usually with whitish bloom. _A.
negundo_, p. 193.

+WINTER KEY TO THE SPECIES OF ACER+

a. Terminal buds usually under 1/4 inch in length.

b. Buds white-woolly; twigs usually with a whitish bloom;
opposite leaf-scars meeting; fruit often persistent on the tree
until spring. _A. negundo_, p. 193.

bb. Buds not white-woolly; twigs without whitish bloom;
opposite leaf-scars not meeting; fruit not persistent on the
tree in winter.

c. Buds reddish or greenish; twigs bright red.

d. Twigs strictly glabrous; buds glabrous; spherical flower
buds clustered on the sides of the shoot; pith pink; large
trees.

e. Twigs rank-smelling when broken; tip of outer bud-scales
often apiculate; tips of branches curving upwards; bark
separating into long, thin flakes loose at the ends. _A.
saccharinum_, p. 185.

ee. Twigs not rank-smelling when broken; tip of outer
bud-scales rounded; tips of branches not conspicuously curving
upwards; bark rough-ridged, but seldom forming loose flakes.
_A. rubrum_, p. 187.

dd. Twigs appressed-hairy, at least near the tip; buds somewhat
tomentose; spherical flower buds absent; pith brown; shrub or
bushy tree. _A. spicatum_, p. 179.

cc. Buds brownish; twigs brownish or grayish.

d. Buds glabrous, or somewhat pubescent at the apex only; bark
dark gray on the trunk. _A. saccharum_, p. 181.

dd. Buds hoary-pubescent; bark sometimes almost black on the
trunk. _A. saccharum nigrum_, p. 183.

aa. Terminal buds usually 1/4-1/2 inch in length.

b. Buds reddish; opposite leaf-scars meeting.

c. Buds conspicuously stalked; bud-scales visible, 1 pair; bark
longitudinally white-striped; small tree or large shrub. _A.
pennsylvanicum_, p. 177.

cc. Buds not conspicuously stalked; bud-scales visible, 2-3
pairs; bark not white-striped; large tree. _A. platanoides_, p.
189.

bb. Buds bright green; opposite leaf-scars not meeting. _A.
pseudo-platanus_, p. 191.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1/2.
4. Staminate flowering branchlet, × 1/2.
5. Vertical section of staminate flower, enlarged.
6. Pistillate flowering branchlet, × 1/2.
7. Vertical section of pistillate flower, enlarged.
8. Fruit, × 3/4.]

+ACERACEAE+

+Striped Maple. Moosewood. Whistlewood+

_Acer pennsylvanicum L._

HABIT.--A small tree at best, more often a large shrub, seldom attaining a height of more than 30 feet, with a short trunk 5-8 inches through. The striped, upright branches form a rather compact crown.

LEAVES.--Opposite, simple, 5-6 inches long and nearly as broad; 3-lobed above the middle with short, tapering lobes; palmately 3-nerved; sharply doubly serrate; rounded or heart-shaped at the base; glabrous, yellow-green above, paler beneath, turning pale yellow in autumn; petioles stout, grooved.

FLOWERS.--May-June, when the leaves are nearly full grown; usually monoecious; large, bright yellow, bell-shaped, in slender, drooping racemes 4-6 inches long; calyx 5-parted; petals 5; stamens 7-8; ovary downy.

FRUIT.--Ripens in autumn; glabrous, paired samaras in long, drooping, racemose clusters, the wings 3/4 inch long, widely divergent, and marked on one side of each nutlet by a small cavity.

WINTER-BUDS.--Bright red; terminal bud nearly 1/2 inch long, short-stalked, with bud-scales keeled; lateral buds smaller, appressed.

BARK.--Twigs light green, mottled with black, smooth; trunk and branches red-brown, marked longitudinally by broad, pale stripes.

WOOD.--Light, soft, close-grained, pinkish brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Abundant in the Upper Peninsula, extending southward as far as Roscommon County in the Lower Peninsula.

HABITAT.--Cool, rocky or sandy woods, usually in the shade of other trees.

NOTES.--In the Northwoods the green shoots are browsed by deer and moose. Valued mostly for its aesthetic qualities. Of little or no economic value.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1/2.
4. Flowering branchlet, × 1/2.
5. Staminate flower, enlarged.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+ACERACEAE+

+Mountain Maple+

_Acer spicatum Lam._

HABIT.--A bushy tree sometimes 25-30 feet high, with a short trunk 6-8 inches in diameter; small, upright branches form a small, rounded crown. More often a straggling shrub.

LEAVES.--Opposite, simple, 4-5 inches long and two-thirds as broad; 3-lobed above the middle, the lobes coarsely crenate-serrate with pointed teeth, the sinuses usually wide-angled and acute at the base; thin; glabrous, dark green above, covered with a whitish down beneath, turning scarlet and orange in autumn; veining prominent; petioles long, slender, with enlarged base.

FLOWERS.--June, after the leaves are full grown; polygamo-monoecious; small, yellow-green; in erect, slightly compound, many-flowered, long-stemmed, terminal racemes; calyx downy, 5-lobed; petals 5; stamens 7-8; ovary tomentose.

FRUIT.--July; bright red, turning brown in late autumn; small, glabrous, paired samaras, in pendulous, racemose clusters.

WINTER-BUDS.--Small, flattish, acute, bright red, more or less tomentose; the terminal 1/8 inch long, containing the flowers.

BARK.--Twigs reddish, slightly hairy; very thin, red-brown, smooth or slightly furrowed on the trunk.

WOOD.--Light, soft, close-grained, light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Common in the Upper Peninsula; extends as far south as Saginaw Bay.

HABITAT.--Damp forests; rocky woods; along streams; always in the shade of other trees.

NOTES.--Forms much of the undergrowth of our northern forests. Little used, except for fire-wood.

1. Winter twig, × 2.
2. Portion of twig, enlarged.
3. Leaf, × 1/2.
4. Staminate flowering branchlet, × 1/2.
5. Staminate flower, enlarged.
6. Pistillate flowering branchlet, × 1/2.
7. Pistillate flower, enlarged.
8. Fruit, × 1.]

+ACERACEAE+

+Sugar Maple. Hard Maple. Rock Maple+

_Acer saccharum Marsh._ [_Acer saccharinum Wang._]

HABIT.--A stately tree 60-100 feet in height, with a trunk diameter of 3-4 feet; in the open forming stout, upright branches near the ground, in forests making remarkably clean trunks to a good height; the crown is a broad, round-topped dome.

LEAVES.--Opposite, simple, 3-5 inches long and broad; usually 5-lobed (sometimes 3-lobed), the lobes sparingly wavy-toothed, the sinuses broad and rounded at the base; thin and firm; opaque, dark green above, lighter and glabrous beneath, turning yellow and red in autumn; petioles long, slender.

FLOWERS.--May, with the leaves; polygamo-monoecious or dioecious; on thread-like, hairy pedicels in nearly sessile corymbs; greenish yellow; calyx campanulate, 5-lobed; corolla 0; stamens 7-8; ovary hairy.

FRUIT.--September-October, germinating the following spring; paired samaras, glabrous, with wings about 1 inch long, diverging slightly.

WINTER-BUDS.--Small, acute, red-brown, glabrous or somewhat pubescent toward the apex, the terminal 1/4 inch long, the lateral smaller, appressed.

BARK.--Twigs smooth, pale brown, becoming gray and smooth on the branches; old trunks dark gray, deeply furrowed, often cleaving up at one edge in long, thick plates.

WOOD.--Heavy, hard, strong, close-grained, tough, durable, light brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Found throughout the entire state.

HABITAT.--Prefers moist, rich soil in valleys and uplands and moist, rocky slopes.

NOTES.--The most important hardwood in Michigan. The tree which produces the bulk of the maple sugar of the market.

1. Winter twig, × 2.
2. Leaf, × 1/2.
3. Flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flower, enlarged.
6. Fruit, × 1.]

+ACERACEAE+

+Black Maple. Black Sugar Maple+

_Acer saccharum nigrum (Michx. f.) Britt._ [_Acer nigrum Michx._]

HABIT.--A stately tree, sometimes reaching a height of 80 feet, with a trunk diameter of 2-3 feet; branches stout, forming a broad, rounded, symmetrical crown.

LEAVES.--Opposite, simple, concave, 5-7 inches across, the breadth usually exceeding the length; usually 5-lobed at maturity, the two lower lobes being small, often reduced to a mere curve in the outline, the pointed lobes undulate or entire and narrowed from the broad, shallow sinuses; thick and firm; glabrous above, downy beneath; petioles stout, usually pendent, tomentose. The sides of the larger leaves often droop giving to the tree an air of depression.

FLOWERS.--May, with the leaves; monoecious; in nearly sessile, umbel-like corymbs; about 1/4 inch long, yellow, on slender, hairy pedicels 2-3 inches long; calyx campanulate, pilose, 5-lobed; corolla 0; stamens 7-8; ovary hairy.

FRUIT.--Ripens in autumn; glabrous, paired samaras, clustered on drooping pedicels; wings set wide apart, but only slightly diverging.

WINTER-BUDS.--Small, ovoid, acute, with dark red-brown, acute scales, hoary-pubescent on the outer surface.

BARK.--Twigs smooth, pale gray; becoming thick, deeply furrowed and sometimes almost black on the trunk.

WOOD.--Hard, heavy, strong, close-grained, creamy white, with thin, lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula, south-eastern portion.

HABITAT.--Prefers low, moist, rich soil of river-bottoms, but does well on gravelly soils and uplands.

NOTES.--Very variable. A very good shade tree because of its dense foliage. It is claimed by some that the finest grades of maple sugar are made from the sap of this tree.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1/2.
4. Staminate flowering branchlet, × 1.
5. Staminate flower, enlarged.
6. Pistillate flowering branchlet, × 1.
7. Pistillate flower, enlarged.
8. Fruit, × 1/2.]

+ACERACEAE+

+Silver Maple. Soft Maple+

_Acer saccharinum L._ [_Acer dasycarpum Ehrh._]

HABIT.--A beautiful tree, growing to a height of 60-80 feet, with a trunk diameter of 2-4 feet, usually separating near the ground into 3-4 upright stems which are destitute of branches for a considerable distance. Usually the long, slender branches bend downwards, but with their tips ascending in a graceful curve. Crown broad, especially in its upper portion.

LEAVES.--Opposite, simple, 3-6 inches long and nearly as broad; usually 5-lobed by narrow, acute sinuses which extend nearly to the midrib, the lobes often sublobed, sharply toothed; light green above, silvery white beneath, turning pale yellow in autumn; petioles long, slender, drooping.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or dioecious; small, yellow-green, in crowded, sessile umbels; calyx 5-lobed (sometimes each lobe again divided); corolla 0; stamens 3-7; ovary hairy.

FRUIT.--May, germinating as soon as it reaches the ground; paired samaras, large, glabrous, curving inwards, one samara often aborted.

WINTER-BUDS.--Dark red, blunt; the terminal about 1/4 inch long, with bud-scales often apiculate at the apex; flower-buds clustered on side spurs.

BARK.--Twigs smooth, red-gray, lustrous; young trunks gray, smooth; old trunks dark gray, more or less furrowed, separating into thin, loose scales.

WOOD.--Hard, strong, close-grained, rather brittle, perishable, pale brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula south of Saginaw Bay.

HABITAT.--Prefers low, rich bottom-lands, subject to occasional inundation, but not in swamps.

NOTES.--A rapid grower, adapting itself to a variety of soils. Does not do well on dry, elevated ground. The first tree to blossom in early spring.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 1.
4. Fascicle of staminate flowers, × 1.
5. Staminate flower, enlarged.
6. Fascicle of pistillate flowers, × 1.
7. Pistillate flower, enlarged.
8. Fruit, × 3/4.]

+ACERACEAE+

+Red Maple. Soft Maple+

_Acer rubrum L._

HABIT.--A medium-sized tree 40-50 feet high, occasionally in swamps 60-75 feet; trunk 1-3 feet in diameter; upright branches, which form a low, rather narrow, rounded crown.

LEAVES.--Opposite, simple, 3-4 inches long and nearly as broad; 3-5-lobed by broad, acute sinuses, the lobes irregularly doubly serrate or toothed; glabrous, green above, whitish and generally glabrous beneath, turning bright scarlet in autumn; petioles long, slender.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or dioecious; in few-flowered fascicles on shoots of the previous year, the pistillate red, the staminate orange; sepals 4-5; petals 4-5; stamens 5-8; ovary smooth.

FRUIT.--May-June, germinating immediately after reaching the ground; samaras small, on drooping pedicels 2-4 inches long; wings about 1 inch long, diverging at about a right angle.

WINTER-BUDS.--Dark red, blunt; terminal bud about 1/8 inch long, with bud-scales rounded at the apex; flower-buds clustered on side spurs.

BARK.--Twigs bright red, lustrous, becoming smooth and light gray on the branches; old trunks dark gray, ridged, separating into plate-like scales.

WOOD.--Heavy, close-grained, not strong, light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Throughout the entire state.

HABITAT.--Prefers swamp-lands or banks of streams; rarely found on hillsides.

NOTES.--A valuable shade and ornamental tree. Sugar has been made in small quantities from the sap.

1. Winter twig, × 1.
2. Leaf, × 1/2.
3. Raceme of staminate flowers, × 1/2.
4. Staminate flower, enlarged.
5. Raceme of pistillate flowers, × 1/2.
6. Pistillate flower, enlarged.
7. Fruit, × 1/2.]

+ACERACEAE+

+Norway Maple+

_Acer platanoides L._

HABIT.--A tall, handsome tree, with a height of 40-60 feet, and a trunk diameter of 1-2 feet, having a round, spreading crown of stout branches, resembling _A. saccharum_. Twigs coarse.

LEAVES.--Opposite, simple, 5-7 inches broad, and almost as long; thin; 5-7-lobed at maturity, lobes remotely coarse-toothed with the teeth drawn out into filamentous points, separated by rounded, scallop-like sinuses; glabrous, bright green both sides, turning pale yellow in autumn; petioles long, slender, exuding a milky juice when cut.

FLOWERS.--May-June, before or with the leaves; dioecious; large, yellow-green, in erect, short, flat racemes; sepals 5; petals 5; stamens 8.

FRUIT.--Ripens in autumn and germinates the following spring; pendent on long stalks; large, glabrous, paired samaras, with wings 2 inches long, diverging by nearly 180°.

WINTER-BUDS.--Yellow-green, red or dull red-brown; terminal bud about 1/4 inch long, broad, short-stalked, with bud-scales strongly keeled; lateral buds small, appressed; buds exuding a milky juice when cut.

BARK.--Twigs lustrous, light brown to greenish; trunk dark gray, becoming closely fissured, not scaly.

WOOD.--Moderately heavy, hard, close-grained, whitish or brownish, with white sapwood.

NOTES.--Exotic from Europe. Extensively planted in cities for its abundant shade. The roots strike deep and spread laterally, enabling the tree to hold its own in a city environment. It holds its leaves two weeks longer in autumn than do our native maples. A rapid grower.

1. Winter twig, × 1.
2. Leaf, × 1/2.
3. Flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Perfect flower, enlarged.
6. Fruit, × 1/2.]

+ACERACEAE+

+Sycamore Maple+

_Acer pseudo-platanus L._

HABIT.--A thrifty tree 50-60 feet high, with a trunk diameter of 2-3 feet; the crown roundish, spreading.

LEAVES.--Opposite, simple, 4-7 inches across, and as long as broad; thick; pentagonally 5-lobed, the lobes more or less ovate, separated by very narrow, acute sinuses extending about half-way to the midrib, the lobes coarsely and irregularly blunt-serrate, crenate-serrate, or slightly lobed; upper surface dark green and shining, somewhat wrinkled, but paler dull green and glaucous beneath; petioles long, stout.

FLOWERS.--April, before the leaves; polygamo-monoecious; large, greenish yellow, in pendent racemes of umbellate cymes of about three each; sepals 5; petals 5; stamens 8, hairy; ovary hairy.

FRUIT.--Ripens in autumn and germinates the following spring; pendent on long stalks; large, glabrous, paired samaras, with wings 1-1/2 inches long, diverging at about a right angle.

WINTER-BUDS.--Bright green; terminal bud 1/4-1/2 inch long, ovoid to subglobose, blunt, with bud-scales more or less keeled; lateral buds small, divergent.

BARK.--Twigs lustrous, brown or gray, becoming slate colored on the branches; trunk gray or brownish, smooth or flaking off in short scales.

WOOD.--Moderately heavy, hard, compact, brownish, with white sapwood.

NOTES.--Exotic from Europe. Much planted in our cities, where it is thrifty, but short-lived. The crown is rather too broad for planting anywhere except on our widest streets. The leaves last two weeks longer in autumn than do those of our native maples.

1. Winter twig, × 1.
2. Leaf, × 1/2.
3. Staminate flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flowering branchlet, × 1/2.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+ACERACEAE+

+Boxelder. Ash-leaved Maple+

_Acer negundo L._ [_Negundo aceroides Muench._]

HABIT.--A sturdy little tree 30-50 feet high, with a trunk diameter of 1-2 feet. Trunk often divides near the ground into several stout, wide-spreading branches, forming a broad, unsymmetrical, open crown.

LEAVES.--Opposite, pinnately compound. Leaflets 3-5 in number, 2-4 inches long, 1-1/2-2-1/2 inches broad; ovate or oval; nearly entire, irregularly and remotely coarse-toothed above the middle, or sometimes 3-lobed (often giving the leaflet a jagged outline); apex acute, base variable; glabrous or somewhat pubescent at maturity, with prominent veins. Petioles slender, 2-3 inches long, the enlarged base leaving prominent crescent-shaped scars partly surrounding the winter-buds.

FLOWERS.--April, before or with the leaves; dioecious; small, yellow-green; the staminate in clusters on long, thread-like, hairy pedicels; the pistillate in narrow, drooping racemes; calyx hairy, 5-lobed; corolla 0; stamens 4-6; ovary pubescent.

FRUIT.--Early summer, but hanging until late autumn or early spring; narrow, flat, winged samaras, in pairs, clustered in drooping, racemose clusters.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, acute, inclosed in two dull red scales, often hoary or minutely pubescent; lateral buds obtuse, appressed.

BARK.--Twigs greenish to purple, glaucous; trunk pale gray or light brown, deeply cleft into broad ridges.

WOOD.--Light, soft, close-grained, weak, creamy white, with thick, hardly distinguishable sapwood.

DISTRIBUTION.--Lower Peninsula as far north as Saginaw Bay.

HABITAT.--Banks of streams and borders of swamps. Prefers deep, moist soil.

NOTES.--Accommodates itself to almost any situation. Easily transplanted. Much planted for shade and ornament. Fast-growing, but short-lived.

+SUMMER KEY TO THE SPECIES OF AESCULUS+

a. Leaflets usually 5; foliage ill-smelling when bruised; bark
broken into thick plates; prickly bur about 1 inch in
diameter. _A. glabra_, p. 199.

aa. Leaflets usually 7; foliage not ill-smelling when bruised;
bark broken into thin plates; prickly bur about 2 inches in
diameter. _A. hippocastanum_, p. 197.

+WINTER KEY TO THE SPECIES OF AESCULUS+

a. Terminal bud about 2/3 inch long; bud-scales covered with a
glaucous bloom, not conspicuously resinous; bark broken into
thick plates; prickly bur about 1 inch in diameter. _A.
glabra_, p. 199.

aa. Terminal bud 1-1-1/2 inches long; bud-scales conspicuously
sticky-resinous, glistening; bark broken into thin plates;
prickly bur about 2 inches in diameter. _A. hippocastanum_, p.
197.

1. Winter twig, × 3/4.
2. Leaf, × 1/6.
3. Leaflet, × 1/2.
4. Flower, × 1.
5. Fruit, × 1/2.]

+SAPINDACEAE+

+Horse-chestnut+

_Aesculus hippocastanum L._

HABIT.--A handsome tree, with a height of 40-60 feet and a trunk diameter of 1-2 feet, forming a broad, conical crown. The regularly occurring branches ascend from the trunk at first, gradually bend downwards as they lengthen, and end in a thick, upturning spray.

LEAVES.--Opposite, digitately compound. Leaflets usually 7, rarely 5, 5-7 inches long, 1-1/2-2-1/2 inches broad; obovate, wedge-shaped at the base; irregularly and bluntly serrate; thick; rough, dark green above, paler beneath, turning a rusty yellow in autumn. Petioles long, grooved, swollen at the base.

FLOWERS.--May-June, after the leaves; polygamo-monoecious; large, whitish, in showy, upright, terminal thyrses 8-12 inches long; pedicels jointed, 4-6-flowered; calyx campanulate, 5-lobed; petals 5, white, spotted with yellow and red, clawed; stamens 7, thread-like, longer than the petals.

FRUIT.--October; a leathery, globular capsule about 2 inches in diameter, roughened with short spines; containing 1-3 large, smooth, lustrous, brown nuts, marked by large, pale scars.

WINTER-BUDS.--Terminal buds 1-1-1/2 inches long, acute, brownish, covered with glistening, resinous gum; inner scales yellowish, becoming 1-1/2-2 inches long in spring, remaining until the leaves are nearly half grown.

BARK.--Twigs smooth, red-brown; trunk dark brown and broken into thin plates by shallow fissures; rich in tannin, bitter.

WOOD.--Light, soft, close-grained, weak, whitish, with thin, light brown sapwood.

NOTES.--A native of Greece, extensively cultivated throughout Europe and America, where it is a favorite shade tree. A double-flowered variety, _Aesculus hippocastanum, v. flòre plèno_, which bears no fruit is a common garden form.

1. Winter twig, × 1.
2. Leaf, × 1/6.
3. Leaflet, × 1/2.
4. Flower, × 2.
5. Fruit, × 1/2.
6. Nut, × 1/2.]

+SAPINDACEAE+

+Ohio Buckeye+

_Aesculus glabra Willd._

HABIT.--A medium-sized tree 30-50 feet in height, with a trunk not over 2 feet in diameter; usually much smaller; slender, spreading branches, forming a broad, rounded crown; twigs thick.

LEAVES.--Opposite, digitately compound. Leaflets usually 5, rarely 7, 3-6 inches long, 1-1/2-2-1/2 inches broad; ovate or oval, gradually narrowed to the entire base; irregularly and finely serrate; glabrous, yellow-green above, paler beneath, turning yellow in autumn. Petioles 4-6 inches long, slender, enlarged at the base. Foliage ill-smelling when bruised.

FLOWERS.--April-May, after the leaves; polygamo-monoecious; small, yellow-green, in terminal panicles 5-6 inches long and 2-3 inches broad, more or less downy; pedicels 4-6-flowered; calyx campanulate, 5-lobed; petals 4, pale yellow, hairy, clawed; stamens 7, with long, hairy filaments.

FRUIT.--October; a thick, leathery, prickly capsule, about 1 inch in diameter, containing a single large, smooth, lustrous, brown nut. A large pale scar gives the name "Buckeye".

WINTER-BUDS.--Terminal buds 2/3 inch long, acute, resinous, brownish; inner scales yellow-green, becoming 1-1/2-2 inches long in spring and remaining until the leaves are nearly half grown.

BARK.--Twigs smooth, red-brown, becoming ashy gray; old trunks densely furrowed and broken into thick plates; ill-smelling when bruised.

WOOD.--Light, soft, close-grained, weak, whitish, with thin, light brown sapwood.

NOTES.--A native of the Mississippi River Valley. Occasionally planted in southern Michigan for ornamental purposes, but is less popular than the Horse-chestnut.

1. Winter twig, × 1.
2. Leaf, × 1/2.
3. Cyme of flowers, with its bract, × 1/2.
4. Flower, with two petals, petaloid scales
and stamens removed, enlarged.
5. Stamen, enlarged.
6. Fruit, × 1/2.]

+TILIACEAE+

+Basswood+

_Tilia americana L._

HABIT.--A tree usually 60-70 feet high, with a tall, straight trunk 2-4 feet in diameter; numerous slender branches form a dense, ovoid or rounded crown.

LEAVES.--Alternate, simple, 5-6 inches long, 3-4 inches broad; obliquely heart-shaped; coarsely serrate; thick and firm; glabrous, dull dark green above, paler beneath; petioles slender, 1-2 inches long.

FLOWERS.--June-July, after the leaves; perfect, regular; yellowish white, downy, fragrant; borne on slender pedicels in loose, drooping cymes, the peduncle attached for half its length to a narrow, oblong, yellowish bract; sepals 5, downy; petals 5, creamy white; stamens numerous, in 5 clusters; ovary 5-celled; stigma 5-lobed.

FRUIT.--October; globose, nut-like, woody, gray, tomentose, about the size of peas.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, often lopsided, smooth, dark red, 1/4 inch long.

BARK.--Twigs smooth, reddish gray, becoming dark gray or brown; dark gray and smooth on young stems, on old trunks thick, deeply furrowed into broad, scaly ridges.

WOOD.--Light, soft, close-grained, tough, light red-brown, with thick sapwood of nearly the same color.

DISTRIBUTION.--Common in most parts of the Lower Peninsula, frequent in the Upper Peninsula.

HABITAT.--Prefers rich, well-drained, loamy soils.

NOTES.--Rapid in growth. Easily transplanted. Recommended for street and ornamental planting.

+SUMMER KEY TO THE SPECIES OF CORNUS+

a. Leaves mostly alternate; branches usually greenish; flowers
not surrounded by large petal-like bracts; fruit globular,
blue, borne many in loose clusters. _C. alternifolia_, p. 207.

aa. Leaves opposite; branches usually reddish or yellowish;
flowers surrounded by large petal-like bracts; fruit ovoid,
scarlet, borne in close clusters of 3-4. _C. florida_, p. 205.

+WINTER KEY TO THE SPECIES OF CORNUS+

a. Leaf-scars mostly alternate; buds light brown; branches
usually greenish. _C. alternifolia_, p. 207.

aa. Leaf-scars opposite; buds greenish; branches usually
reddish or yellowish. _C. florida_, p. 205.

1. Winter twig, with leaf buds, × 1.
2. Portion of twig, enlarged.
3. Winter twig, with flower bud, × 1.
4. Leaf, × 1/2.
5. Flowering branchlet, × 1/2.
6. Flower, enlarged.
7. Fruit, × 1.]

+CORNACEAE+

+Flowering Dogwood. Dogwood. Boxwood+

_Cornus florida L._

HABIT.--A bushy tree with a height of 15-30 feet and a short trunk 8-12 inches in diameter; slender, spreading branches form a flat-topped crown.

LEAVES.--Opposite, closely clustered at the ends of the branchlets, simple, 3-5 inches long, 2-3 inches broad; ovate to elliptical; obscurely wavy-toothed; thick and firm; bright green, covered with minute, appressed hairs above, pale and more or less pubescent beneath, turning bright scarlet in autumn; petioles short, grooved.

FLOWERS.--May, with the leaves; perfect; greenish; in dense clusters, surrounded by 4 large, white or pinkish, petal-like bracts (often mistaken for the corolla), borne on short, stout peduncles; calyx 4-lobed, light green; petals 4, yellow-green; stamens 4, alternate with the petals; ovary 2-celled.

FRUIT.--October; an ovoid, scarlet drupe, borne in close clusters of 3-4; flesh is bitter.

WINTER-BUDS.--Leaf-buds narrow-conical, acute, greenish; flower-buds spherical or vertically flattened, grayish.

BARK.--Twigs pale green, becoming red or yellow-green their first winter, later becoming light brown or red-gray; red-brown or blackish on the trunk, often separating into quadrangular, plate-like scales.

WOOD.--Heavy, hard, strong, tough, close-grained, brownish, with thick, lighter colored sapwood.

DISTRIBUTION.--Southern Michigan as far north as the Grand-Saginaw Valley.

HABITAT.--Prefers rich, well-drained soil, usually under the shade of other trees.

NOTES.--A valuable species for ornamental purposes. Rather slow of growth.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 3/4.
4. Flowering branchlet, × 1/2.
5. Flower, enlarged.
6. Fruiting branchlet, × 1/2.]

+CORNACEAE+

+Blue Dogwood. Alternate-leaved Dogwood+

_Cornus alternifolia L. f._

HABIT.--A small tree or large shrub reaching a height of 25-30 feet and a trunk diameter of 6-8 inches; more often smaller than this. The long, slender branches are arranged in irregular whorls, forming flat, horizontal tiers, giving the tree a storied effect.

LEAVES.--Mostly alternate and clustered at the ends of the branchlets; simple, 3-5 inches long, 2-1/2-3 inches broad; oval or ovate, long-pointed, wedge-shaped at the base; obscurely wavy-toothed; thin; dark green, nearly glabrous above, paler and covered with appressed hairs beneath, turning yellow and scarlet in autumn; petioles slender, grooved, hairy, with clasping bases.

FLOWERS.--May-June, after the leaves; perfect; borne on slender pedicels in many-flowered, irregular, open cymes from the season's shoots; calyx cup-shaped, obscurely 4-toothed, covered with fine, silky, white hairs; petals 4, cream colored; stamens 4; ovary 2-celled.

FRUIT.--October; a globular, blue-black drupe, borne in loose, red-stemmed clusters; flesh bitter.

WINTER-BUDS.--Leaf-buds small, acute, light brown; flower-buds spherical or vertically flattened.

BARK.--Twigs greenish or reddish, becoming smooth, dark green; thin, dark red-brown and shallowly fissured on the trunk.

WOOD.--Heavy, hard, close-grained, red-brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Scattered throughout both peninsulas.

HABITAT.--Prefers moist, well-drained soil on the borders of streams and swamps, often in the shade of other trees.

NOTES.--Hardy throughout the state. Easily transplanted. The only _Cornus_ with alternate leaves and branches.

1. Winter twig, × 1.
2. Portion of twig, enlarged.
3. Leaf, × 3/4.
4. Staminate flowering branchlet, × 1/2.
5. Staminate flower, enlarged.
6. Pistillate flowering branchlet, × 1/2.
7. Pistillate flower, enlarged.
8. Fruit, × 1/2.]

+CORNACEAE+

+Black Gum. Pepperidge+

_Nyssa sylvatica Marsh._ [_Nyssa multiflora Wang._]

HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-2 feet, forming a rounded to cylindrical crown of slender, spreading, pendulous branches and a stiff, flat spray.

LEAVES.--Alternate, simple, 2-5 inches long, one-half as broad; oblong-obovate to oval; entire, or sometimes wavy-margined; thick and firm; very lustrous and dark green above, pale and often hairy beneath, turning bright scarlet, on the upper surface only, in autumn; petioles short.

FLOWERS.--May-June, with the leaves; polygamo-dioecious; greenish; borne on slender, downy peduncles; the staminate slender-pedicelled, in many-flowered heads; the pistillate sessile, in several-flowered clusters; calyx cup-shaped, 5-toothed; petals 5; stamens 5-10; stigma stout, terete, recurved.

FRUIT.--October; fleshy drupes, ovoid, blue-black, about 1/2 inch long, sour, in clusters of 1-3.

WINTER-BUDS.--1/8-1/4 inch long, ovoid, obtuse, dark red.

BARK.--Twigs greenish or light brown, smooth or often downy, becoming smooth, dark red-brown; thick, red-brown on old trunks, deeply furrowed.

WOOD.--Heavy, soft, strong, very tough, difficult to split, not durable in contact with the soil, pale yellow, with thick, whitish sapwood.

DISTRIBUTION.--Frequent in the southern half of the Lower Peninsula. Has been reported as far north as Manistee.

HABITAT.--Prefers the borders of swamps and low, wet lands. Rarely flourishes in exposed situations.

NOTES.--Of great ornamental value. Not easily transplanted. Pith of twigs with thin, transverse partitions.

+SUMMER KEY TO THE SPECIES OF FRAXINUS+

a. Lateral leaflets sessile. _F. nigra_, p. 221.

aa. Lateral leaflets petioluled.

b. Twigs, petioles and lower sides of leaves pubescent. _F.
pennsylvanica_, p. 215.

bb. Twigs, petioles and lower sides of leaves essentially
glabrous.

c. Twigs prominently 4-angled. _F. quadrangulata_, p. 219.

cc. Twigs terete.

d. Lower sides of leaves essentially of the same color as the
upper; leaflet-margins rather finely sharp-serrate. _F.
pennsylvanica lanceolata_, p. 217.

dd. Lower sides of leaves paler than the upper;
leaflet-margins entire or obscurely serrate. _F. americana_,
p. 213.

WINTER KEY TO THE SPECIES OF FRAXINUS

a. Twigs prominently 4-angled; fruit falling in early autumn.
_F. quadrangulata_, p. 219.

aa. Twigs terete; fruit often persistent on the tree until
mid-winter or the following spring.

b. Buds rusty-tomentose; twigs more or less downy. _F.
pennsylvanica_, p. 215.

bb. Buds not tomentose; twigs not downy.

c. Terminal bud black or nearly so, showing 3 pairs of scales
in cross-section; bud-scales apiculate at the apex; samaras
with broad wings, the seed portion flattish; bark flaky,
rubbing off on the hand. _F. nigra_, p. 221.

cc. Terminal bud brownish, showing 4 pairs of scales in
cross-section; bud-scales rounded at the apex; samaras with
narrow wings, the seed portion terete; bark ridged, not flaky
and rubbing off on the hand.

d. Upper margin of leaf-scars deeply concave. _F. americana_,
p. 213.

dd. Upper margin of leaf-scars not concave, but straight
across or projecting upward. _F. pennsylvanica lanceolata_, p.
217.

1. Winter twig, × 1.
2. Leaf, × 1/4.
3. Staminate flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flowering branchlet, × 1/2.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+OLEACEAE+

+White Ash+

_Fraxinus americana L._

HABIT.--A large tree 50-75 feet high, with a trunk diameter of 2-3 feet; forming an open, pyramidal crown of long, slender, lateral branches and a stout, rather sparse spray.

LEAVES.--Opposite, pinnately compound, 8-12 inches long. Leaflets usually 7-9, 3-5 inches long, 1-2 inches broad; short-stalked; ovate to oblong-lanceolate; entire or obscurely serrate; thick and firm; glabrous, dark green above, paler beneath. Petioles glabrous, stout, grooved.

FLOWERS.--May, before the leaves; dioecious; borne in loose panicles on shoots of the previous season; calyx campanulate, 4-lobed; corolla 0; stamens 2, rarely 3; ovary 2-celled.

FRUIT.--August-September, persistent on the branches until mid-winter or the following spring; samaras 1-2 inches long, in crowded, drooping, paniculate clusters 6-8 inches long.

WINTER-BUDS.--Short, rather obtuse; bud-scales apiculate, keeled, 4 pairs, rusty-brown.

BARK.--Twigs at first dark green, becoming gray or light brown, often covered with a glaucous bloom; gray, deeply furrowed into firm, narrow, flattened ridges on the trunk.

WOOD.--Heavy, hard, strong, close-grained, tough, brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Of common occurrence throughout the state.

HABITAT.--Prefers a rich, moist, loamy soil, but grows in any well-drained situation; common along stream-beds.

NOTES.--Grows rapidly. Easily transplanted. Fairly free from disease. Leaves appear late in spring.

1. Winter twig, × 1.
2. Leaf, × 1/3.
3. Staminate flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flowering branchlet, × 1/2.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+OLEACEAE+

+Red Ash+

_Fraxinus pennsylvanica Marsh._ [_Fraxinus pubescens Lam._]

HABIT.--A medium-sized tree 30-50 feet high, with a trunk diameter of 1-2 feet; stout, upright branches and slender branchlets form a compact, broad, irregular crown.

LEAVES.--Opposite, pinnately compound, 10-12 inches long. Leaflets 7-9, 3-5 inches long, 1-1-1/2 inches broad; short-stalked; oblong-lanceolate to ovate; slightly serrate or entire; thin and firm; glabrous, yellow-green above, pale and silky-downy beneath. Petioles stout, pubescent.

FLOWERS.--May, with the leaves; dioecious; borne in compact, downy panicles on shoots of the previous season; calyx cup-shaped, 4-toothed; corolla 0; stamens 2, rarely 3; ovary 2-celled.

FRUIT.--Early autumn, persistent on the branches throughout the winter; samaras 1-2 inches long, in open, paniculate clusters.

WINTER-BUDS.--Small, rounded; bud-scales rounded on the back, 3 pairs, rusty-brown, tomentose.

BARK.--Twigs pale-pubescent at first, lasting 2-3 years or often disappearing during the first summer, finally ashy gray or brownish and often covered with a glaucous bloom; brown or dark gray on the trunk, with many longitudinal, shallow furrows; somewhat scaly.

WOOD.--Heavy, hard, strong, brittle, coarse-grained, light brown, with thick, yellow-streaked sapwood.

DISTRIBUTION.--Not a common tree. Most frequent in the southern half of the Lower Peninsula, but has been reported further north, i.e., Drummond's Island and Keweenaw County, Upper Peninsula.

HABITAT.--Prefers wet or moist, rich loam; river-banks; swampy lowlands.

NOTES.--A rapid grower in youth. Fairly immune from insect and fungous diseases.

1. Winter twig, × 1.
2. Leaf, × 1/3.
3. Staminate flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flowering branchlet, × 1/2.
6. Pistillate flower, enlarged.
7. Fruit, × 1.]

+OLEACEAE+

+Green Ash+

_Fraxinus pennsylvanica lanceolata (Borkh.) Sarg._ [_Fraxinus lanceolata Borkh._] [_Fraxinus viridis Michx. f._]

Considered by some authors to be a distinct species, and by others a variety of _F. pennsylvanica Marsh._, which it resembles. The main points of difference are:

The usual absence of pubescence from the branchlets,
the underside of the leaflets, and the petioles.

The rather narrower, shorter, and more sharply
serrate leaflets.

The color of the leaves, which is bright green on both
sides.

A very hardy tree, of rapid growth and desirable habit, making it useful for ornamental and street planting. Easily transplanted.

Of rare occurrence in Michigan, but has been reported from several localities.

1. Winter twig, × 1.
2. Leaf, × 1/2.
3. Flowering branchlet, × 1.
4. Flower, enlarged.
5. Fruit, × 1/2.]

+OLEACEAE+

+Blue Ash+

_Fraxinus quadrangulata Michx._

HABIT.--A large tree 50-80 feet high, with a trunk diameter of 1-3 feet; small, spreading branches and stout, 4-angled, more or less 4-winged branchlets form a narrow crown.

LEAVES.--Opposite, pinnately compound, 8-12 inches long. Leaflets 5-9, usually 7, 3-5 inches long, 1-2 inches broad; short-stalked; ovate-oblong to lanceolate, long-pointed; coarsely serrate; thick and firm; yellow-green above, paler beneath, glabrous. Petioles slender, glabrous.

FLOWERS.--April, before the leaves; perfect; borne in loose panicles on shoots of the previous season; calyx reduced to a ring; corolla 0; stamens 2; ovary 2-celled.

FRUIT.--September-October, falling soon after; samaras 1-2 inches long, in long, loose, paniculate clusters.

WINTER-BUDS.--Short, rather obtuse; bud-scales rounded on the back, 3 pairs, dark red-brown, somewhat pubescent.

BARK.--Twigs orange, rusty-pubescent, becoming brownish or grayish; on the trunk light gray tinged with red, irregularly divided into large, plate-like scales, often with the shaggy appearance of a Shagbark Hickory.

WOOD.--Heavy, hard, close-grained, brittle, light yellow-streaked with brown, with thick, light yellow sapwood.

DISTRIBUTION.--Occasionally in the southern half of the Lower Peninsula. Nowhere abundant.

HABITAT.--Prefers rich, limestone hills, but grows well in fertile bottom-lands.

NOTES.--Hardy and grows rapidly. A blue dye is made by macerating the inner bark in water.

1. Winter twig, × 1.
2. Leaf, × 1/3.
3. Staminate flowering branchlet, × 1/2.
4. Staminate flower, enlarged.
5. Pistillate flowering branchlet, × 1/2.
6. Pistillate flowers, enlarged.
7. Fruit, × 1.]

+OLEACEAE+

+Black Ash+

_Fraxinus nigra Marsh._ [_Fraxinus sambucifolia Lam._]

HABIT.--A tall tree 60-80 feet high, with a trunk diameter of 1-2 feet; slender, upright branches form in the forest a narrow crown, in the open a rounded, ovoid crown.

LEAVES.--Opposite, pinnately compound, 12-16 inches long. Leaflets 7-11, 3-5 inches long, 1-2 inches broad; sessile, except the terminal; oblong to oblong-lanceolate, long-pointed; remotely, but sharply serrate; thin and firm; dark green above, paler beneath, glabrous. Petioles stout, grooved, glabrous.

FLOWERS.--May, before the leaves; polygamo-dioecious; borne in loose panicles on shoots of the preceeding season; calyx 0; corolla 0; stamens 2; ovary 2-celled.

FRUIT.--August-September, falling early, or sometimes hanging on the tree until the following spring; samaras 1-1-1/2 inches long, in open, paniculate clusters 8-10 inches long.

WINTER-BUDS.--Ovoid, pointed; bud-scales rounded on the back, 3 pairs, almost black.

BARK.--Twigs at first dark green, becoming ashy gray or orange, finally dark gray and warted; thin, soft ash-gray and scaly on the trunk. Bark flakes off on rubbing with the hand.

WOOD.--Heavy, tough, coarse-grained, weak, rather soft, dark brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Common throughout most portions of Michigan.

HABITAT.--Prefers deep, cold swamps and low river-banks, but grows in any good soil.

NOTES.--Hardy throughout the state. Not easily transplanted. Foliage falls early in autumn.

+SUMMER KEY TO THE SPECIES OF CATALPA+

a. Leaves 5-8 inches long, thick; flowers 1-1/2 inches across,
prominently yellow-spotted; seeds with _pointed_, fringed
wings at each end; branches rather crooked and straggling;
bark thin, separating into thin scales on the trunk. _C.
bignonioides_, p. 227.

aa. Leaves 8-12 inches long, thin; flowers 2-1/2 inches
across, not prominently spotted; seeds with _rounded_,
wide-fringed wings at each end; branches not crooked and
straggling; bark thick, separating into thick scales on the
trunk. _C. speciosa_, p. 225.

+WINTER KEY TO THE SPECIES OF CATALPA+

a. Fruiting capsules about 1/4 inch thick; seeds with
_pointed_, fringed wings at each end; branches rather crooked
and straggling; bark thin, separating into thin scales on the
trunk. _C. bignonioides_, p. 227.

aa. Fruiting capsules about 1/2 inch thick, seeds with
_rounded_, wide-fringed wings at each end; branches not
crooked and straggling; bark thick, separating into thick
scales on the trunk. _C. speciosa_, p. 225.

1. Winter twig, × 1.
2. Leaf, × 1/4.
3. Panicle of flowers, × 3/8.
4. Fruit, × 1/2.
5. Seed, × 1.]

+BIGNONIACEAE+

+Hardy Catalpa+

_Catalpa speciosa Warder._

HABIT.--A tree 50-75 feet high, with a short, often crooked trunk and a broad, rounded crown of slender, spreading branches and thick branchlets.

LEAVES.--Opposite or whorled, simple, 8-12 inches long, 6-8 inches broad; heart-shaped; entire or sometimes slightly lobed; thick and firm; glabrous, dark green above, downy beneath, with clusters of dark, nectariferous glands in the axils of the primary veins, turning black and falling with the first severe frost; petioles long, stout, terete.

FLOWERS.--June-July, after the leaves are full grown; perfect; borne on slender, purplish pedicels in open, few-flowered panicles 5-6 inches long; calyx 2-lobed, purple; corolla white with inconspicuous yellow spots, campanulate, 5-lobed, 2-1/2 inches broad; stamens 2, staminodia 3; ovary 2-celled.

FRUIT.--Ripens in early autumn; slender, 2-celled, cylindrical capsule 10-20 inches long and about 1/2 inch thick; hangs on tree all winter, opening in spring before falling; seeds light brown, 1 inch long, with rounded, wide-fringed wings at each end.

WINTER-BUDS.--Terminal bud absent; lateral buds brownish, globose, inconspicuous.

BARK.--Twigs greenish, often with purple tinge, becoming orange or red-brown and covered with a slight bloom the first winter, finally darker with age; thick, red-brown, broken into thick scales on the trunk.

WOOD.--Light, soft, weak, coarse-grained, light brown, with very thin, almost white sapwood; very durable in contact with the soil.

NOTES.--A native of Illinois, Indiana, and the states adjoining on the south, but much planted in Michigan as a shade and ornamental tree. Closely resembles _C. bignonioides_, but is a larger and hardier tree.

1. Winter twig, × 1.
2. Leaf, × 3/8.
3. Panicle of flowers, × 1/3.
4. Fruit, × 1/2.
5. Seed, × 1.]

+BIGNONIACEAE+

+Catalpa+

_Catalpa bignonioides Walt._ [_Catalpa catalpa (L.) Karst._]

HABIT.--A tree 40-30 feet high, with a short, thick trunk and a broad, irregular crown of long, crooked branches and coarse, upright branchlets.

LEAVES.--Opposite or whorled, simple, 5-8 inches long, 4-5 inches broad; heart-shaped; entire or sometimes slightly lobed; thin and firm; glabrous, light green above, downy beneath, with dark, nectariferous glands in the axils of the primary veins, turning black and falling with the first severe frost; petioles long, stout, terete.

FLOWERS.--June-July, after the leaves are full grown; perfect; borne on slender, hairy pedicels in compact, many-flowered panicles 8-10 inches long; calyx 2-lobed, green or purple; corolla white with yellow spots, campanulate, 5-lobed, 1-1/2 inches broad; stamens 2, staminodia 3; ovary 2-celled.

FRUIT.--Ripens in early autumn; slender, 2-celled, cylindrical capsule 8-20 inches long and about 1/4 inch thick; hangs on tree all winter, opening in spring before falling; seeds silvery gray, 1 inch long, with pointed, fringed wings at each end.

WINTER-BUDS.--Terminal bud absent; lateral buds, brownish, globose, inconspicuous.