cc. Buds pale-pubescent above the middle, but usually glabrous

below, not lustrous; inner bark of trunk red. [2] _Q. coccinea_, p. 113.

+FAGACEAE+

+White Oak+

_Quercus alba L._

HABIT.--A large tree 60-80 feet high, with a trunk diameter of 2-4 feet; forming a short, thick trunk with stout, horizontal, far-reaching limbs, more or less gnarled and twisted in old age, and a broad, open crown.

LEAVES.--Alternate, simple, 5-9 inches long, about one-half as broad; obovate to oblong; 5-9-lobed, some with broad lobes and shallow sinuses, others with narrow lobes and deep, narrow sinuses, the lobes usually entire; thin and firm; glabrous, bright green above, pale or glaucous beneath; often persistent on the tree through the winter.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy catkins 2-3 inches long; the pistillate sessile or short-peduncled, reddish, tomentose; calyx campanulate, 6-8-lobed, yellow, hairy; corolla 0; stamens 6-8, with yellow anthers; stigmas red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; cup with small, brown-tomentose scales, inclosing one-fourth of the nut; nut oblong-ovoid, rounded at the apex, about 3/4 inch long, light brown; kernel sweet and edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid, obtuse; scales smooth, dark red-brown.

BARK.--Twigs at first bright green, tomentose, later reddish, and finally ashy gray; thick, light gray or whitish on old trunks, shallowly fissured into broad, flat ridges.

WOOD.--Very heavy, strong, hard, tough, close-grained, durable, light brown, with thin, light brown sapwood.

DISTRIBUTION.--Rare in the Upper Peninsula, common in the Lower Peninsula, especially in the lower half.

HABITAT.--Grows well in all but very wet soils, in all open exposures.

NOTES.--Slow and even of growth. Difficult to transplant.

+FAGACEAE+

+Bur Oak+

_Quercus macrocarpa Michx._

HABIT.--A large tree 60-80 feet high, with a trunk 2-4 feet in diameter; great, spreading branches form a broad, rugged crown.

LEAVES.--Alternate, simple, 6-10 inches long and one-half as broad; obovate to oblong, wedge-shaped at the base; crenately lobed, usually cut nearly to the midrib by two opposite sinuses near the middle; thick and firm; dark green and shining above, pale-pubescent beneath; petioles short, stout.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, hairy catkins 4-6 inches long; the pistillate sessile or short-stalked, reddish, tomentose; calyx 4-6-lobed, yellow-green, downy; corolla 0; stamens 4-6, with yellow anthers; stigmas bright red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; very variable in size and shape; cup typically deep, cup-shaped, tomentose, fringed at the rim, inclosing one-third or all of the nut; nut broad-ovoid, 1/2-1-1/2 inches long, brownish, pubescent; kernel white, sweet and edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid or conical, red-brown, pale-pubescent.

BARK.--Twigs yellow-brown, thick-tomentose, becoming ash-gray or brownish; branches with corky ridges; thick and gray-brown on the trunk, deeply furrowed.

WOOD.--Heavy, hard, strong, tough, close-grained, very durable, brownish, with thin, pale sapwood.

DISTRIBUTION.--Common throughout both peninsulas.

HABITAT.--Prefers rich, moist soil; bottom-lands; but is tolerant of many soils.

NOTES.--Rather slow of growth. Difficult to transplant.

+FAGACEAE+

+Swamp White Oak. Swamp Oak+

_Quercus bicolor Willd._ [_Quercus platanoides (Lam.) Sudw._]

HABIT.--A large tree 50-70 feet high, with a trunk diameter of 2-3 feet; forming a rather open, rugged crown of tortuous, pendulous branches and short, stiff, bushy spray.

LEAVES.--Alternate, simple, 5-7 inches long, 3-5 inches broad; obovate to oblong-obovate; coarsely sinuate-crenate or shallow-lobed; thick and firm; dark green and shining above, whitish and more or less tomentose beneath; petioles stout, about 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy catkins 3-4 inches long; the pistillate tomentose, on long, tomentose peduncles, in few-flowered spikes; calyx deeply 5-9-lobed, yellow-green, hairy; corolla 0; stamens 5-8, with yellow anthers; stigmas bright red.

FRUIT.--Autumn of first season; acorns on pubescent stems 1-4 inches long, usually in pairs; cup cup-shaped, with scales somewhat loose (rim often fringed), inclosing one-third of the nut; nut ovoid, light brown, pubescent at the apex, about 1 inch long; kernel white, sweet, edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, broadly ovoid to globose, obtuse; scales light brown, pilose above the middle.

BARK.--Twigs at first lustrous, green, becoming red-brown, finally dark brown and separating into large, papery scales which curl back; thick, gray-brown on the trunk, deeply fissured into broad, flat, scaly ridges.

WOOD.--Heavy, hard, strong, tough, coarse-grained, light brown, with thin, indistinguishable sapwood.

DISTRIBUTION.--Southern half of Lower Peninsula.

HABITAT.--Prefers moist, rich soil bordering swamps and along streams.

NOTES.--Fairly rapid in growth and reasonably easy to transplant.

+FAGACEAE+

+Chinquapin Oak. Chestnut Oak. Yellow Oak+

_Quercus muhlenbergii Engelm._ [_Quercus acuminata (Michx.) Houba_]

HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-3 feet; erect, somewhat short branches form a narrow, rounded crown.

LEAVES.--Alternate, simple, 4-7 inches long, 1-4 inches broad; oblong-lanceolate to obovate; coarsely toothed; thick and firm; lustrous, yellow-green above, pale-pubescent beneath; petioles slender, about 1 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy catkins 3-4 inches long; the pistillate sessile or in short spikes, hoary-tomentose; calyx campanulate, 5-8-lobed, yellow, hairy; corolla 0; stamens 5-8, with yellow anthers; stigmas red.

FRUIT.--Autumn of first season; sessile or short-stalked acorns; cup with small scales, hoary-tomentose, inclosing one-half of the nut; nut ovoid, about 3/4 inch long, light brown; kernel sweet, sometimes edible.

WINTER-BUDS.--Terminal bud 1/8 inch long, conical, acute; scales chestnut-brown, scarious on the margin.

BARK.--Twigs greenish at first, becoming gray-brown, finally gray or brown; thin, silvery gray or ash colored and flaky on the trunk.

WOOD.--Heavy, very hard, strong, close-grained, durable, dark brown, with thin, pale brown sapwood.

DISTRIBUTION.--Confined to the southern half of the Lower Peninsula.

HABITAT.--Prefers a limestone soil; dry hillsides; rich bottom-lands; rocky river-banks.

NOTES.--Grows uniformly until maturity. Leaves resemble those of the Chestnut. A form which differs from the type in having broader, obovate leaves broadest above the middle and a flaky bark has been described and named _Quercus Alexanderi Britton_.

+FAGACEAE+

+Red Oak+

_Quercus rubra L._

HABIT.--A large tree 70-80 feet high, with a trunk diameter of 2-4 feet; forming a broad, rounded crown of a few large, wide-spreading branches and slender branchlets.

LEAVES.--Alternate, simple, 5-9 inches long, 4-6 inches broad; oval to obovate; 5-11-lobed with coarse-toothed, bristle-tipped lobes tapering from broad bases and wide, oblique, rounded sinuses; thin and firm; dull dark green above, paler beneath; petioles stout, 1-2 inches long.

FLOWERS.--April-May, when the leaves are half grown; monoecious; the staminate in hairy catkins 4-5 inches long; the pistillate on short, glabrous peduncles; calyx 4-5-lobed, greenish; corolla 0; stamens 4-5, with yellow anthers; stigmas long, spreading, bright green.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup shallow, saucer-shaped, inclosing only the base of the nut; scales closely appressed, more or less glossy, puberulous, bright red-brown; nut oblong-ovoid with a broad base, about 1 inch long, red-brown; kernel white, very bitter.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, acute, light brown, smooth.

BARK.--Twigs lustrous, green, becoming reddish, finally dark brown; young trunks smooth, gray-brown; old trunks darker, shallowly fissured into thin, firm, broad ridges; inner bark light red, not bitter.

WOOD.--Heavy, hard, strong, coarse-grained, light red-brown, with thin, darker colored sapwood.

DISTRIBUTION.--Southern portion of Lower Peninsula as far north as Roscommon County.

HABITAT.--Prefers rich, moist loam; glacial drift; stream-banks. Grows well in all well-drained soils.

NOTES.--Grows rapidly. A good street tree.

+FAGACEAE+

+Pin Oak+

_Quercus palustris Muench._

HABIT.--A medium-sized tree 40-50 feet high, with a trunk diameter of 1-2 feet; forming an oblong or pyramidal crown of many upright, spreading branches, the lowermost drooping nearly to the ground.

LEAVES.--Alternate, simple, 4-6 inches long, 2-4 inches broad; obovate to ovate; 5-7-lobed by deep, wide, rounded sinuses, the lobes few-toothed, bristle-tipped; thin and firm; very lustrous, dark green above, paler beneath; petioles slender.

FLOWERS.--May, with the leaves; monoecious; the staminate in hairy catkins 2-4 inches long; the pistillate tomentose, borne on short, tomentose peduncles; calyx 4-5-lobed, hairy; corolla 0; stamens 4-5, with yellow anthers; stigmas recurved, bright red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup saucer-shaped with scales closely appressed, dark red-brown, inclosing only the base of the nut; nut nearly hemi-spherical, about 1/2 inch in diameter, light brown; kernel bitter.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid or conical, acute, light brown, smooth.

BARK.--Twigs dark red and tomentose at first, becoming lustrous, green, finally gray-brown; thick, gray-brown and smoothish on the trunk.

WOOD.--Heavy, hard, strong, coarse-grained, light brown, with thin, darker colored sapwood.

DISTRIBUTION.--Confined to the most southern portions of the Lower Peninsula.

HABITAT.--Prefers moist, rich soil; river-bottoms; borders of swamps.

NOTES.--Grows rapidly and uniformly. Easily transplanted. The tiny branchlets at a distance give the impression of the tree being full of pins.

+FAGACEAE+

+Scarlet Oak+

_Quercus coccinea Muench._

HABIT.--A tree 40-50 feet high and 12-15 inches in trunk diameter; long, slender branches form a rather open, rounded crown.

LEAVES.--Alternate, simple, 3-6 inches long and nearly as broad; broadly obovate to oval; 5-9-lobed by deep, wide, rounded sinuses, the lobes toothed and bristle-tipped; thin and firm; shining, bright green above, paler beneath, both sides glabrous; turning brilliant scarlet in autumn; petioles slender, 1-2 inches long.

FLOWERS.--May, with the leaves; monoecious; the staminate in glabrous catkins 3-4 inches long; the pistillate on pubescent peduncles 1/2 inch long, bright red, pubescent; calyx 4-5-lobed, reddish, pubescent; corolla 0; stamens usually 4, with yellow anthers; stigmas long, spreading, bright red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup top-shaped to cup-shaped, with closely imbricated, slightly puberulous, red-brown scales, inclosing about one-half of the nut; nut usually short-ovoid, 1/2-3/4 inch long, light red-brown; kernel whitish, bitter.

WINTER-BUDS.--Terminal bud about 1/4 inch long, broadly ovoid, acute, dark red-brown, pale-pubescent above the middle.

BARK.--Twigs at first scurfy-pubescent, later lustrous, green, finally smooth, light brown; thick, dark gray or brown on old trunks, shallowly fissured, scaly; inner bark red, not bitter.

WOOD.--Heavy, hard, strong, coarse-grained, light red-brown, with thick, darker brown sapwood.

DISTRIBUTION.--Lower Peninsula, southern half.

HABITAT.--Prefers a light, dry, sandy soil.

NOTES.--Rapid of growth. Desirable for ornamental planting.

+FAGACEAE+

+Hill's Oak. Northern Pin Oak. Black Oak+

_Quercus ellipsoidalis E. J. Hill_

HABIT.--A tree 50-60 feet high, with a short trunk 2-3 feet in diameter; forming a rather narrow, oblong crown of upright and horizontal branches. Many small, drooping branches are sent out near the ground, which eventually die; and it is to the stubs or pins which persist about the trunk that the appelation Pin Oak is due.

LEAVES.--Alternate, simple, 3-7 inches long and about as broad; oval to nearly orbicular; narrowly 5-7-lobed by deep, wide, rounded sinuses, the lobes few-toothed, bristle-tipped; thin and firm; lustrous, bright green above, paler beneath, both sides glabrous except for the tufts of hairs in the axils of the veins beneath; petioles slender, glabrous.

FLOWERS.--May, with the leaves; monoecious; the staminate in puberulous catkins 2-3 inches long; the pistillate red, tomentose, borne on stout, tomentose, 1-3-flowered peduncles; calyx 2-5-lobed or-parted, glabrous except at the apex, which is fringed with long, twisted hairs; corolla 0; stamens 2-5, with short filaments; stigmas 3, recurved, dark red.

FRUIT.--Autumn of second season; short-stalked or nearly sessile acorns; cup top-shaped, with scales thin, puberulous, inclosing one-third to one-half of the nut; nut ellipsoid, 1/2-3/4 inch long, light brown, puberulous; kernel yellow, bitter.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, ovoid, rather obtuse, slightly angular, lustrous, red-brown.

BARK.--Twigs bright red-brown, covered with matted, pale hairs, becoming glabrous, dark gray or brown; thin, dull gray to dark brown, rather smooth or closely ribbed on the trunk; inner bark yellow.

WOOD.--Heavy, hard, strong, coarse-grained, red-brown, with thin, paler sapwood.

DISTRIBUTION.--South-western part of the Lower Peninsula, but limits not definitely known.

HABITAT.--Well-drained uplands, especially on clays; occasionally on the borders of ponds and in low woods.

NOTES.--A new and comparatively little known species.

+FAGACEAE+

+Yellow Oak. Black Oak+

_Quercus velutina Lam._

HABIT.--A medium-sized tree 50-60 feet high and 1-3 feet in trunk diameter; slender branches and stout branchlets form a wide-spreading, rounded crown.

LEAVES.--Alternate, simple, 5-10 inches long, 3-8 inches broad; ovate to oblong; usually 7-lobed, some with shallow sinuses and broad, rounded, mucronate lobes, others with wide, rounded sinuses extending half-way to the midrib or farther and narrow-oblong or triangular, bristle-tipped lobes, the lobes more or less coarse-toothed, each tooth bristle-tipped; thick and leathery; dark green and shining above, pale and more or less pubescent beneath; petioles stout, yellow, 3-6 inches long.

FLOWERS.--May, when the leaves are half grown; monoecious; the staminate in pubescent catkins 4-6 inches long; the pistillate reddish, on short, tomentose peduncles; calyx acutely 3-4-lobed, reddish, hairy; corolla 0; stamens usually 4-5, with acute, yellow anthers; stigmas 3, divergent, red.

FRUIT.--Autumn of second season; sessile or short-stalked acorns; cup cup-shaped or turbinate, inclosing about one-half of the nut; scales thin, light brown, hoary; nut ovoid, 1/2-3/4 inch long, red-brown, often pubescent; kernel yellow, bitter.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid to conical, obtuse, strongly angled, hoary-tomentose.

BARK.--Twigs at first scurfy-pubescent, later glabrous, red-brown, finally mottled gray; thick and nearly black on old trunks, deeply furrowed and scaly; inner bark thick, yellow, very bitter.

WOOD.--Heavy, hard, strong, coarse-grained, bright red-brown, with thin, paler sapwood.

DISTRIBUTION.--Southern half of the Lower Peninsula.

HABITAT.--Prefers glacial drift; dry or gravelly uplands; poor soils.

NOTES.--Rapid of growth. Undesirable for street use.

+FAGACEAE+

+Black Jack+

_Quercus marilandica Muench._

HABIT.--A small, shrubby tree 20-30 feet high, with a trunk diameter of 6-14 inches; spreading, often contorted branches form a rounded or obovoid crown.

LEAVES.--Alternate, simple, 5-7 inches long and broad; broad-obovate; more or less 3-lobed at the apex, the lobes entire or toothed, bristle-tipped, very variable in size and shape; thick and leathery; very lustrous and dark green above, yellowish and scurfy-pubescent beneath; petioles short, stout.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, hoary catkins 2-4 inches long; the pistillate rusty-tomentose, on short, rusty-tomentose peduncles; calyx 4-5-lobed, thin, scarious, tinged with red, pale-pubescent; corolla 0; stamens 4, with apiculate, red anthers; stigmas recurved, dark red.

FRUIT.--Autumn of second season; short-stalked acorns; cup turbinate, with large, red-brown, rusty-tomentose scales, inclosing about one-half of the nut; nut subglobose, about 3/4 inch long, yellow-brown, puberulous; kernel yellowish.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, acute, prominently angled; scales light red-brown, rusty-hairy.

BARK.--Twigs at first light red and scurfy, later glabrous, red-brown, and finally brown or ashy gray; thick and almost black on the trunk, divided into nearly square plates.

WOOD.--Heavy, hard, strong, dark brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Southern Michigan (Ann Arbor and Lansing).

HABITAT.--Dry, sandy or clay barrens.

NOTES.--Rare in Michigan.

+FAGACEAE+

+Shingle Oak+

_Quercus imbricaria Michx._

HABIT.--A tree 40-50 feet high, with a trunk diameter of 1-2 feet; forming a rather open, rounded crown of slender, horizontal branches.

LEAVES.--Alternate, simple, 4-6 inches long, 1-2 inches broad; oblong-lanceolate to oblong-obovate; entire or somewhat undulate; thin, very lustrous, dark green above, paler and pubescent beneath; petioles stout, pubescent, 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, hoary-tomentose catkins 2-3 inches long; the pistillate on slender, tomentose peduncles; calyx 4-lobed, yellow, downy; corolla 0; stamens 4-5, with yellow anthers; stigmas short, recurved, greenish yellow.

FRUIT.--Autumn of second season; acorns on stout peduncles 1/2 inch long; cup cup-shaped, with red-brown, downy scales, inclosing one-third to one-half of the nut; nut subglobose, about 1/2 inch long, dark brown, often striate; kernel very bitter.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid, acute, lustrous, brown.

BARK.--Twigs lustrous, dark green, becoming brown; thick on old trunks, light brown and slightly fissured.

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

DISTRIBUTION.--Of rare occurrence in Michigan. Reported in Kalamazoo, St. Joseph and Washtenaw Counties, Lower Peninsula.

HABITAT.--Rich uplands; fertile river-bottoms.

NOTES.--Desirable for ornamental uses. Hardy. Rapid of growth.

+SUMMER KEY TO THE SPECIES OF ULMUS+

a. Leaves essentially smooth on both sides; branches often with corky, wing-like ridges; lowermost branches usually short and strongly drooping; main trunk usually continuous into the crown without dividing, giving to the tree a narrow-oblong outline. _U. racemosa_, p. 129.

aa. Leaves usually rough on one or on both sides; branches without corky ridges; lowermost branches not short, not strongly drooping; main trunk usually dividing into several large limbs, giving to the tree a more or less vase-shaped outline.

b. Leaves usually rough above, but smooth beneath, with petioles glabrous; bark of trunk gray, deeply fissured into broad, scaly ridges; inner bark not mucilaginous. _U. americana_, p. 127.

bb. Leaves usually rough both sides, with petioles hairy; bark of trunk dark red-brown, shallowly fissured into large, loose plates; inner bark mucilaginous. _U. fulva_, p. 125.

+WINTER KEY TO THE SPECIES OF ULMUS+

a. Buds conspicuously rusty-tomentose; twigs more or less pubescent; inner bark very mucilaginous when chewed. _U. fulva_, p. 125.

aa. Buds not conspicuously rusty-tomentose; twigs glabrous; inner bark not mucilaginous.

b. Bundle-scars usually 3; buds 1/8 inch long, glabrous; twigs without corky ridges; outline of tree vase-shaped. _U. americana_, p. 127.

bb. Bundle-scars usually 4-6 in a curved line; buds 1/4 inch long, somewhat pilose; twigs often with corky ridges; outline of tree narrow-oblong. _U. racemosa_, p. 129.

+URTICACEAE+

+Slippery Elm. Red Elm+

_Ulmus fulva Michx._ [_Ulmus pubescens Walt._]

HABIT.--A medium-sized tree 40-60 feet high, with a short trunk 1-2 feet in diameter; spreading branches form a broad, open, flat-topped crown.

LEAVES.--Alternate, simple, 4-7 inches long, about one-half as broad; ovate-oblong; coarsely doubly serrate; thick and firm; dark green and rough above, paler and somewhat rough beneath; petioles short, stout, hairy.

FLOWERS.--March-April, before the leaves; mostly perfect; borne on short pedicels in crowded fascicles; calyx campanulate, 5-9-lobed, green, hairy; corolla 0; stamens 5-9, with dark red anthers; stigmas 2, reddish purple.

FRUIT.--May; semi-orbicular, 1-seeded samaras, short-stalked in dense clusters; seed cavity brown-tomentose; wings smooth, nearly 3/4 inch long.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, obtuse, dark brown, rusty-tomentose, 1/4 inch long.

BARK.--Twigs at first bright green and pubescent, becoming light to dark brown or grayish; thick on old trunks, dark red-brown, shallowly fissured into large, loose plates; inner bark mucilaginous.

WOOD.--Heavy, hard, strong, very close-grained, durable, easy to split while green, dark red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Of frequent occurrence throughout the state.

HABITAT.--Prefers stream-banks and bottom-lands; rich, moist hillsides; rocky ridges and slopes.

NOTES.--Grows more rapidly than _U. americana_.

+URTICACEAE+

+White Elm. American Elm. Water Elm+

_Ulmus americana L._

HABIT.--A tree 75-100 feet high, with a trunk diameter of 2-6 feet; commonly dividing 20-30 feet above the ground into a few large branches which rise upward and outward to form a vase-shaped outline.

LEAVES.--Alternate, simple, 4-6 inches long, one-half as broad; obovate-oblong to oval; coarsely doubly serrate; thick and firm; dark green and rough above, pale and pubescent or glabrous beneath; petioles short and stout.

FLOWERS.--March-April, before the leaves; mostly perfect; small, brown to red; borne on slender pedicels in loose fascicles; calyx campanulate, 5-9-lobed; corolla 0; stamens 4-9, with bright red anthers; ovary 2-celled; styles 2, green.

FRUIT.--May; ovate, 1-seeded samaras, smooth both sides, hairy on the margin, 1/2 inch long, long-stemmed in crowded clusters.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, flattened, glabrous, brown, 1/8 inch long.

BARK.--Twigs at first light green and downy, becoming glabrous, red-brown, finally ash-gray; on old trunks thick, ash-gray, deeply fissured into broad, scaly ridges.

WOOD.--Heavy, hard, strong, tough, difficult to split, coarse-grained, light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers deep, rich, moist loam; bottom-lands; stream-banks.

NOTES.--Grows rapidly. Long-lived. The roots run along near the surface of the ground for a great distance. An ideal street tree.

+URTICACEAE+

+Cork Elm. Rock Elm+

_Ulmus racemosa Thomas_ [_Ulmus Thomasi Sarg._]

HABIT.--A large tree sometimes reaching a height of 100 feet and a trunk diameter of 5 feet, but usually somewhat smaller; strongly drooping lateral and lower branches form a narrow, oblong crown.

LEAVES.--Alternate, simple, 3-6 inches long, one-half as broad; obovate to oblong-oval, more or less dished; coarsely doubly serrate; thick and firm; lustrous, dark green above, pale-pubescent beneath; petioles pubescent, 1/4 inch long.

FLOWERS.--March-April, before the leaves; mostly perfect; greenish; borne on slender, drooping pedicels in loose racemes; calyx campanulate, 7-8-lobed; corolla 0; stamens 7-8, with purple anthers; ovary hairy, 2-styled.

FRUIT.--May; ovate, 1-seeded samaras, pubescent all over, 1/2 inch long.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, acute, brown, pilose, 1/4 inch long.

BARK.--Twigs at first light brown and pubescent, becoming lustrous, red-brown, finally gray-brown with corky, wing-like ridges; thick and grayish on the trunk, with wide fissures separating broad, flat, scaly ridges.

WOOD.--Heavy, very strong and tough, close-grained, light red-brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Frequent in the southern third of the Lower Peninsula.

HABITAT.--Dry, gravelly uplands; rocky ridges and slopes; heavy clay soils; river-banks.

NOTES.--A good street tree, but less graceful in habit than _U. americana_.

+URTICACEAE+

+Hackberry. Nettle-tree+

_Celtis occidentalis L._

HABIT.--A medium-sized tree, 40-60 feet high, with a short, straight trunk 1-2 feet in diameter which branches a few feet from the ground into a few large limbs and many slender, horizontal, zigzag branches, forming a broad, rounded crown.

LEAVES.--Alternate, simple, 2-4 inches long and one-half as broad; ovate to ovate-lanceolate, oblique at the base, usually long-pointed; coarsely serrate above the entire base; thin; glabrous, light green above, paler beneath, turning light yellow late in autumn; petioles short, slender, hairy.

FLOWERS.--May, with or soon after the leaves; polygamo-monoecious; greenish; inconspicuous; on slender pedicels; the staminate in clusters at the base of the shoot, the pistillate usually solitary in the axils of the upper leaves; calyx greenish, deeply 5-lobed; corolla 0; stamens 5; ovary 1-celled.

FRUIT.--September-October, remaining on the tree through the winter; slender-stalked, fleshy, globular drupes, 1/4 inch long, dark purple; edible.

WINTER-BUDS.--Terminal bud absent; lateral buds light brown, 1/4 inch long, ovoid, acute, flattened, the tip appressed.

BARK.--Twigs greenish, puberulous, becoming lustrous, red-brown in their first winter; on old trunks thick, light brown or silvery gray, broken into deep, short ridges or warty excrescences.

WOOD.--Heavy, soft, coarse-grained, weak, light yellow, with thick, whitish sapwood.

DISTRIBUTION.--Common throughout the Lower Peninsula.

HABITAT.--Prefers rich, moist, well-drained soil, but will grow on gravelly or rocky hillsides. Common along river-banks.

NOTES.--Hardy throughout its range. Grows slowly and irregularly in youth. Easily transplanted. Not desirable as a street tree, but appears well in ornamental grounds. Very tolerant of shade.

+URTICACEAE+

+Osage Orange+

_Maclura pomifera (Raf.) Schneider_ [_Toxylon pomiferum Raf._] [_Maclura aurantiaca Nutt._]

HABIT.--A tree 20-30 feet high, with a short trunk 1-2 feet in diameter; divides into a few large limbs with curving branches, forming a symmetrical, rounded crown.

LEAVES.--Alternate, simple, 3-5 inches long, 2-3 inches broad; ovate to oblong-lanceolate; entire; thick and firm; dark green and shining above, paler beneath; petioles slender, pubescent, 1-1/2-2 inches long.

FLOWERS.--June, after the leaves; dioecious; the staminate slender-pedicelled, borne in a dense raceme at the end of long, slender, drooping peduncles; the pistillate in dense, globose heads at the end of short, stout peduncles; calyx 4-lobed, hairy; corolla 0; stamens 4; style covered with white, stigmatic hairs.

FRUIT.--Autumn; pale green, orange-like, 4-5 inches in diameter, composed of numerous small drupes, crowded and grown together.

WINTER-BUDS.--Terminal bud absent; lateral buds depressed-globular, partly hidden in the bark, pale brown.

BARK.--Twigs at first bright green, pubescent, becoming orange-brown and armed with stout, straight, axillary spines; dark orange-brown on the trunk and deeply furrowed.

WOOD.--Heavy, very hard and strong, flexible, coarse-grained, very durable, bright orange, with thin, lemon colored sapwood.

NOTES.--A native of the South, but hardy throughout Michigan. A desirable ornamental tree. Extensively planted for hedges.

+URTICACEAE+

+Red Mulberry+

_Morus rubra L._

HABIT.--A small tree 20-30 feet high, with a short trunk 10-15 inches in diameter; forming a dense, round-topped crown of stout, spreading branches and more or less zigzag, slender branchlets.

LEAVES.--Alternate, simple, 3-5 inches long, nearly as broad; outline variable, ovate to semi-orbicular, often 3-5-lobed; coarsely serrate; thin; dark blue-green and smooth or rough above, pale and more or less downy beneath; petioles 1-2 inches long, smooth, exuding a milky juice when cut.

FLOWERS.--May, with the leaves; monoecious or dioecious; the staminate in dense spikes 1-2 inches long, on short, hairy peduncles; the pistillate in dense spikes about 1 inch long, on short, hairy peduncles; calyx 4-lobed, hairy; corolla 0; stamens 4, with green anthers; stigmas 2, spreading.

FRUIT.--July; 1 inch long; consisting of drupes about 1/32 inch long, each inclosed in a thickened, fleshy calyx; berry-like; bright red at first, finally blackish; sweet, juicy, edible.

WINTER-BUDS.--Terminal bud absent; lateral buds ovoid, abruptly pointed, 1/4 inch long, lustrous, light brown.

BARK.--Twigs greenish and more or less downy, becoming smooth and brownish; trunk dark brown tinged with red and more or less furrowed.

WOOD.--Light, soft, weak, rather tough, coarse-grained, very durable, pale orange, with thick, lighter colored sapwood.

DISTRIBUTION.--Southern portion of the Lower Peninsula, as far north as the Muskegon river.

HABITAT.--Prefers rich soil in river-bottoms.

NOTES.--Easily transplanted. Grows rapidly in good, moist soil.

+MAGNOLIACEAE+

+Tulip Poplar. Tulip-tree. White-wood+

_Liriodendron tulipifera L._

HABIT.--A large tree 70-100 feet high, with a columnar trunk 2-5 feet in diameter; forming a rather open, conical crown of slender branches.

LEAVES.--Alternate, simple, 5-6 inches long and broad; 4-lobed; entire; lustrous, dark green above, pale or glaucous beneath, turning clear yellow in autumn; petioles slender, angled, 5-6 inches long.

FLOWERS.--May-June, after the leaves; perfect; terminal; solitary on stout peduncles; tulip-shaped, greenish yellow, 1-1/2-2 inches long; sepals 3, greenish, early deciduous; petals 6, in 2 rows, greenish yellow with an orange spot at the base, early deciduous; stamens numerous, somewhat shorter than the petals; pistils numerous, clinging together about a central axis; ovary 1-celled.

FRUIT.--September-October; a narrow, light brown cone 2-1/2-3 inches long, composed of numerous carpels; carpels long, flat, with a 1-2-seeded nutlet at the base, separating from the slender spindle at maturity.

WINTER-BUDS.--Terminal bud 1/2-1 inch long, obtuse, flattish, dark red, covered with a glaucous bloom.

BARK.--Twigs smooth, lustrous, reddish, becoming brownish, and at length gray; ashy gray, thin and scaly on young trunks, becoming thick, brownish, and deeply furrowed with age.

WOOD.--Light, soft, brittle, weak, easily worked, light yellow or brown, with thin, cream-white sapwood.

DISTRIBUTION.--Lower Peninsula south of the Grand River. Formerly common, but becoming rare.

HABITAT.--Prefers deep, rich, rather moist soil, but adapts itself readily to any good, light soil.

NOTES.--Difficult to transplant, but rapid of growth when once established. Not disfigured by insect enemies. Good for ornamental planting.

+LAURACEAE+

+Sassafras+

_Sassafras variifolium (Salisb.) Ktse._ [_Sassafras sassafras (L.) Karst._] [_Sassafras officinale Nees & Eberm._]

HABIT.--Usually a large shrub, but often a small tree 20-40 feet high, with a trunk diameter of 10-20 inches; stout, often contorted branches and a bushy spray form a flat, rather open crown.

LEAVES.--Alternate, simple, 3-6 inches long, 2-4 inches broad; oval to oblong or obovate; entire or 1-3-lobed with deep, broad sinuses and finger-like lobes; thin; dull dark green above, paler beneath; petioles slender, about 1 inch long.

FLOWERS.--May, with the leaves; dioecious; greenish yellow; on slender pedicels, in loose, drooping, few-flowered racemes 2 inches long; calyx deeply 6-lobed, yellow-green; corolla 0; stamens of staminate flower 9, in 3 rows, of pistillate flower 6, in 1 row; ovary 1-celled.

FRUIT.--September-October; an oblong-globose, lustrous, dark blue berry, 3/8 inch long, surrounded at the base by the scarlet calyx, borne on club-shaped, bright red pedicels.

WINTER-BUDS.--Terminal buds 1/3 inch long, ovoid, acute, greenish, soft-pubescent, flower-bearing; lateral buds much smaller, sterile or leaf-bearing. Aromatic.

BARK.--Twigs glabrous, lustrous, yellow-green, spicy-aromatic, becoming red-brown and shallowly fissured when 2-3 years old; thick, dark red-brown and deeply and irregularly fissured into firm, flat ridges on old trunks.

WOOD.--Soft, weak, brittle, coarse-grained, very durable in the soil, aromatic, dull orange-brown, with thin, light yellow sapwood.

DISTRIBUTION.--Southern portion of Lower Peninsula as far north as Grayling.

HABITAT.--Prefers well-drained, stony or sandy soil; woods; abandoned fields; peaty swamps.

NOTES.--Rapid of growth. Suckers freely. Difficult to transplant. Propagated easily from seed.

+PLATANACEAE+

+Sycamore. Button-wood. Buttonball-tree+

_Platanus occidentalis L._

HABIT.--A large tree 70-100 feet high, with a trunk diameter of 3-8 feet; commonly dividing near the ground into several large secondary trunks, forming a broad, open, irregular crown of massive, spreading branches.

LEAVES.--Alternate, simple, 5-10 inches long and broad; broadly ovate in outline; more or less 3-5-lobed by broad, shallow sinuses, the lobes sinuate-toothed; thin and firm; bright green above, paler beneath, glabrous both sides; petioles stout, puberulous, 1-2 inches long.

FLOWERS.--May, with the leaves; monoecious; borne in dense heads; the staminate dark red, on short, axillary peduncles; the pistillate greenish, on long, slender, terminal peduncles; sepals 3-6, minute; petals 3-6, minute; stamens 3-6, usually 4; styles long, incurved, red.

FRUIT.--October, persistent on the limbs through the winter; brown heads about 1 inch in diameter, on slender, glabrous stems 3-6 inches long.

WINTER-BUDS.--Terminal bud absent; lateral buds 1/4-3/8 inch long, conical, blunt, lustrous, pale brown; forming in summer within the petiole of the leaf.

BARK.--Twigs pale green and tomentose, becoming smooth, dark green, finally grayish; thick, red-brown on the trunk and broken into oblong, plate-like scales, separating higher up into thin plates which peel off, exposing the greenish or yellowish inner bark.

WOOD.--Heavy, tough, hard, rather weak, coarse-grained, difficult to split, light red-brown, with thick, darker colored sapwood.

DISTRIBUTION.--Lower Peninsula as far north as Roscommon County.

HABITAT.--Prefers rich bottom-lands along the borders of rivers and lakes.

NOTES.--Rapid of growth. Bears transplanting well. Often planted as a shade tree. Fungous diseases disfigure it seriously.

+SUMMER KEY TO THE SPECIES OF PYRUS+

a. Leaves simple; fruit a light green pome an inch or more in diameter; branches contorted, bearing many short, spur-like branchlets. _P. coronaria_, p. 145.

aa. Leaves compound; fruit berry-like, 1/4 inch in diameter, bright red; branches not contorted, not bearing many short, spur-like branchlets. _P. americana_, p. 147.

+WINTER KEY TO THE SPECIES OF PYRUS+

a. Bundle-scars 3 or in 3 compound, but distinct groups; buds 1/8-1/4 inch long; branches contorted, bearing many short, spur-like branchlets; fruit a pome an inch or more in diameter, light green. _P. coronaria_, p. 145.

aa. Bundle-scars 4-many in a single U-shaped line, not forming 3 distinct groups; buds about 1/2 inch long; branches not contorted, not bearing many short, spur-like branchlets; fruit berry-like, 1/4 inch in diameter, bright red. _P. americana_, p. 147.

+ROSACEAE+

+Sweet Crab. American Crab+

_Pyrus coronaria L._ [_Malus coronaria Mill._]

HABIT.--Often a bushy shrub, but frequently a small tree 15-25 feet high, with a trunk 8-12 inches in diameter; forming a broad, rounded crown of rigid, contorted branches bearing many short, spur-like branchlets.

LEAVES.--Alternate, simple, 3-4 inches long, almost as broad; ovate to nearly triangular; sharply and deeply serrate, sometimes lobed; membranaceous; bright green above, paler beneath, glabrous both sides; petioles long, slender, often with two dark glands near the middle.

FLOWERS.--May, after the leaves; perfect; 1-1/2-2 inches across; very fragrant; borne on slender pedicels in 5-6-flowered umbels; calyx urn-shaped, 5-lobed, tomentose; petals 5, rose colored to white; stamens 10-20; ovary hairy; styles 5.

FRUIT.--October; a depressed-globose pome, 1-1-1/2 inches in diameter, pale green, very fragrant, with a waxy surface.

WINTER-BUDS.--Terminal bud 1/8-1/4 inch long, obtuse, bright red; lateral buds smaller.

BARK.--Twigs at first hoary-tomentose, becoming glabrous, red-brown; thin, red-brown, breaking into longitudinal fissures on the trunk.

WOOD.--Heavy, rather soft, close-grained, weak, red-brown, with thick, yellow sapwood.

DISTRIBUTION.--Southern portion of the Lower Peninsula as far north as Roscommon County.

HABITAT.--Rich, moist, but well-drained soil in thickets and along streams.

NOTES.--An excellent ornamental tree or shrub for small gardens and shrubberies. The fruit is sometimes gathered for making preserves.

+ROSACEAE+

+Mountain Ash+

_Pyrus americana (Marsh.) DC._ [_Sorbus americana Marsh._]

HABIT.--A small tree 15-20 feet high, with a trunk diameter of not over a foot; branches slender, spreading, forming a narrow, rounded crown.

LEAVES.--Alternate, compound, 6-9 inches long. Leaflets 9-17, 2-3 inches long and 1/2-3/4 inch broad; sessile or nearly so, except the terminal; lanceolate to oblong-lanceolate, taper-pointed; finely and sharply serrate above the entire base; membranaceous; glabrous, dark yellow-green above, paler beneath, turning clear yellow in autumn. Petioles slender, grooved, enlarged at the base.

FLOWERS.--May-June, after the leaves; perfect; 1/8 inch across; borne on short, stout pedicels in many-flowered, flat cymes 3-5 inches across; calyx urn-shaped, 5-lobed, puberulous; petals 5, white; stamens numerous; styles 2-3.

FRUIT.--October, but persistent on the tree throughout the winter; a berry-like pome, subglobose, 1/4 inch in diameter, bright red, with thin, acid flesh; eaten by birds in the absence of other food.

WINTER-BUDS.--Terminal bud about 1/2 inch long, ovoid, acute, with curved apex; lateral buds smaller, appressed; scales rounded on the back, purplish red, more or less pilose above, gummy.

BARK.--Twigs at first red-brown and hairy, becoming glabrous, dark brown; thin, light gray-brown on the trunk, smooth, or slightly roughened on old trees; inner bark fragrant.

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

DISTRIBUTION.--Ludington and northward, principally along the shore of L. Michigan, but common throughout the Upper Peninsula.

HABITAT.--Prefers rich, moist soil on river-banks and on the borders of cold swamps; rocky hillsides and mountains.

NOTES.--More often a shrub. Easily transplanted, but slow of growth. One of the most beautiful trees of our northern forests.

+ROSACEAE+

+Serviceberry+

_Amelanchier canadensis (L.) Medic._

HABIT.--A small tree 25-40 feet in height, with a tall trunk 6-12 inches in diameter; forming a narrow, rounded crown of many small limbs and slender branchlets.

LEAVES.--Alternate, simple, 3-4 inches long and about one-half as broad; ovate to obovate; finely and sharply serrate; glabrous, dark green above, paler beneath; petioles slender, about 1 inch long.

FLOWERS.--April, when the leaves are about one-third grown; perfect; large, white, borne in drooping racemes 3-5 inches long; calyx 5-cleft, campanulate, villous on the inner surface; petals 5, strap-shaped, white, about 1 inch in length; stamens numerous; styles 5, united below.

FRUIT.--June-August; globular, berry-like pome, 1/3-1/2 inch long; turning from bright red to dark purple with slight bloom; sweet and edible when ripe.

WINTER-BUDS.--Yellow-brown, narrow-ovoid to conical, sharp-pointed, 1/4-1/2 inch long; bud-scales apiculate, slightly pubescent.

BARK.--Twigs smooth, light green, becoming red-brown; thin, pale red-brown on the trunk, smoothish or divided by shallow fissures into narrow, longitudinal, scaly ridges.

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

DISTRIBUTION.--Common throughout the state.

HABITAT.--Prefers rich soil of dry, upland woods and hillsides.

NOTES.--Hardy throughout the state. Grows in all soils and situations except in wet lands.

+ROSACEAE+

+The Haws, Thorns, Hawthorns or Thorn-apples+

_Crataegus L._

Owing to the complexity of the various forms in this group, the present state of uncertainty as to the value of certain characters, and the questionable validity of many of the assigned names, it is thought to be beyond the scope of this bulletin to give more than a general description of the group as a whole, recommending the more ambitious student to the various manuals and botanical journals and papers for more detailed information.

The _Crataegi_ are generally low, wide-spreading trees or shrubs, with strong, tortuous branches and more or less zigzag branchlets usually armed with stiff, sharp thorns. The bark varies from dark red to gray and is shallowly fissured or scaly. The leaves are alternate, simple, generally serrate, often lobed, with short or long petioles. The flowers appear in May or June, with or after the leaves, in simple or compound corymbs, whitish or pinkish, perfect. The fruit is a red to yellow, sometimes blue or black pome, subglobose to pear-shaped, with usually dry and mealy flesh and 1-5 seeds. The winter-buds are small, nearly globose, lustrous brown. _Crataegus_ produces wood which is heavy, hard, tough, close-grained, red-brown, with thick, pale sapwood. The Haws are trees of the pasture-lands, the roadside, the open woods and the stream-banks, and are more common in the southern than in the northern portions of the state. Some of the species are desirable as ornaments in parks and gardens on account of their beautiful and abundant flowers and showy fruits.

+SUMMER KEY TO THE SPECIES OF PRUNUS+

a. Leaves oblong-ovate to obovate, abruptly acuminate at the apex; marginal teeth not incurved.

b. Margin of leaves sharp-serrate with spreading teeth; leaves not rugose, the veins not prominent; fruit 1/4-1/2 inch long, bright red, racemose, July-August; bark of trunk brown, smooth or only slightly fissured; usually a large shrub. _P. virginiana_, p. 157.

bb. Margin of leaves crenate-serrate; leaves more or less rugose, the veins prominent; fruit about 1 inch long orange-red, clustered, August-September; bark of trunk gray-brown, early splitting off in large, thick plates; a small tree. _P. nigra_, p. 161.

aa. Leaves oval to oblong-lanceolate, taper-pointed at the apex; marginal teeth incurved.

b. Fruit light red, clustered, July-August; twigs usually less than 1/16 inch thick; pith of twigs brown; tree northern. _P. pennsylvanica_, p. 139.

bb. Fruit black, racemose, August-September; twigs usually more than 1/16 inch thick; pith of twigs white; tree southern. _P. serotina_, p. 155.

+WINTER KEY TO THE SPECIES OF PRUNUS+

a. Terminal bud present; bark of young trunks rather smooth.

b. Buds clustered at the tips of all shoots; twigs usually less than 1/16 inch thick; pith of twigs brown. _P. pennsylvanica_, p. 159.

bb. Buds not clustered, or clustered only on short, spur-like branchlets; twigs usually more than 1/16 inch thick; pith of twigs white.

c. Buds usually 1/4 inch or less in length; bud-scales uniform in color, apiculate at the apex; bark on old trunks blackish, rough-scaly; small to large tree. _P. serotina_, p. 155.

cc. Buds usually 1/4-1/2 inch long; bud-scales grayish on the margins, rounded at the apex; bark on old trunks brown, smooth or only slightly fissured; usually a large shrub. _P. virginiana_, p. 157.

aa. Terminal bud absent; bark of young trunks early splitting off in large, thick plates. _P. nigra_, p. 161.

+ROSACEAE+

+Black Cherry+

_Prunus serotina Ehrh._ [_Padus serotina (Ehrh.) Agardh._]

HABIT.--A medium-sized tree 40-50 feet high and 8-36 inches in trunk diameter; branches few, large, tortuous, forming a rather spreading, oblong or rounded crown.

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.

+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.

+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.

+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.

+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.

+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.

+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.

+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.

+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.