Part 90

Distribution. Moist rocky hillsides usually in the shade of other trees, and really arborescent only on the western slopes of the high mountains of Tennessee and North Carolina; Newfoundland and Labrador to Hudson Bay, Manitoba, and Saskatchewan, and southward through the northern states, and westward to Minnesota and northeastern Iowa, and along the Appalachian Mountains to northern Georgia.

Occasionally cultivated as an ornament of parks and gardens in the northern states.

4. Acer pennsylvanicum L. Striped Maple. Moose Wood.

Leaves rounded or cordate at base, palmately 3-nerved, 3-lobed at apex, with short lobes contracted into a tapering serrate point, and finely and sharply doubly serrate, when they unfold thin, pale rose color and coated with ferrugineous pubescence, especially on the lower surface and on the petioles, and at maturity glabrous with the exception of tufts of ferrugineous hairs in the axils of the principal nerves on the two surfaces, thin, pale green above, rather paler below, 5′—6′ long and 4′—5′ wide; turning in the autumn clear light yellow; petioles stout, grooved, 1½′—2′ in length, with an enlarged base nearly encircling the branch. Flowers bright canary-yellow, opening toward the end of May or early in June when the leaves are nearly fully grown, on slender pedicels ¼′—½′ long, in slender drooping long-stemmed racemes 4′—6′ in length, the staminate and pistillate usually in different racemes on the same plant; sepals linear-lanceolate to obovate, ¼′ long and a little shorter and narrower than the obovate petals; stamens 7—8, shorter than the petals in the staminate flower, rudimentary in the pistillate flower; ovary purplish brown, glabrous, in the staminate flower reduced to a minute point; styles united nearly to the top, with spreading recurved stigmas. Fruit in long drooping racemes, glabrous, with thin spreading wings ¾′ long, and marked on one side of each nutlet by a small cavity; seeds ¼′ long, dark red-brown, and slightly rugose.

A tree, 30°—40° high, with a short trunk 8′—10′ in diameter, small upright branches, and slender smooth branchlets pale greenish yellow at first, bright reddish brown during their first winter, and at the end of two or three years striped like the trunk with broad pale lines; or often much smaller and shrubby in habit. Winter-buds: the terminal conspicuously stipitate, sometimes almost ½′ long, much longer than the axillary buds, covered by two thick bright red spatulate boat-shaped scales prominently keeled on the back, the inner scales green and foliaceous, becoming 1½′—2′ long, ½′ wide, pubescent, and bright yellow or rose color. Bark of the trunk ⅛′—¼′ thick, reddish brown, marked longitudinally by broad pale stripes, and roughened by many oblong horizontal excrescences. Wood light, soft, close-grained, light brown, with thick lighter colored sapwood of 30-40 layers of annual growth.

Distribution. Usually in the shade of other trees, often forming in northern New England a large part of their shrubby undergrowth; shores of Ha-Ha Bay, Quebec, westward along the shores of Lake Ontario and the islands of Lake Huron to northern Wisconsin, and southward through the Atlantic states and along the Appalachian Mountains to northern Georgia; ascending to altitudes of 5000°; common in the north Atlantic states, especially in the interior and elevated regions; of its largest size on the slopes of the Big Smoky Mountains, Tennessee, and of the Blue Ridge in North and South Carolina.

Sometimes cultivated as an ornamental tree in the northern states, and occasionally in Europe.

5. Acer macrophyllum Pursh. Broad-leaved Maple.

Leaves more or less cordate at the broad base, deeply 5-lobed by narrow sinuses acute in the bottom, the lobes acute or acuminate, the terminal lobe often 3-lobed, the others usually furnished with small lateral lobules, the lower lobes much smaller than the others, prominently 3—5-nerved, puberulous when they unfold, especially on the upper surface along the principal veins, and at maturity subcoriaceous, dark green and lustrous on the upper surface, pale on the lower surface, 8′—12′ in diameter; turning in the autumn bright orange color before falling; petioles stout, 10′—12′ in length, with enlarged bases united and encircling the stem and often furnished on the inside with small tufts of white hairs. Flowers bright yellow, fragrant, ¼′ long, on slender pubescent often branched pedicels ½′—¾′ in length, the staminate and pistillate together in graceful pendulous slightly puberulous racemes 4′—6′ long, appearing in April and May after the leaves are fully grown; sepals petaloid, obovate, obtuse and a little longer and broader than the spatulate petals; stamens 9—10, with long slender filaments hairy at base, exserted in the staminate flower and included in the pistillate flower, and orange-colored anthers; ovary hoary-tomentose, reduced in the staminate flower to a minute point; styles united at base only; stigmas long and exserted. Fruit fully grown by the 1st of July and ripening late in the autumn; nutlets covered with long pale hairs, their wings 1½′ long, ½′ wide, slightly divergent and glabrous with the exception of a few hairs on the thickened edge; seeds dark-colored, rugose and pitted, ¼′ long.

A tree, 80°—100° high, with a tall straight trunk 2°—3° in diameter, stout often pendulous branches forming a compact handsome head, and stout branchlets smooth and pale green at first, becoming bright green or dark red in their first winter, covered more or less thickly with small longitudinal white lenticels, and in their second summer gray or grayish brown. Winter-buds obtuse; terminal ¼′ long, with short broad slightly spreading dark red ciliate outer scales rounded on the back, those of the inner ranks green and foliaceous, and at maturity 1½′ long, colored and puberulous; axillary buds minute. Bark of the trunk ½′—¾′ thick, brown faintly tinged with red or bright reddish brown, deeply furrowed and broken on the surface into small square plate-like scales. Wood light, soft, not strong, close-grained, rich brown tinged with red, with thick lighter colored often nearly white sapwood of 60—80 layers of annual growth; more valuable than the wood produced by other deciduous-leaved trees of western North America, and in Washington and Oregon used in the interior finish of buildings, for furniture, and for axe and broom-handles.

Distribution. Banks of streams or on rich bottom-lands or the rocky slopes of mountain valleys; coast of Alaska south of latitude 55° north, southward along the islands and coast of British Columbia, through Washington and Oregon west of the Cascade Mountains, and southward along the coast ranges and the western slopes of the Sierra Nevada to the San Bernardino Mountains, and to Hot Spring Valley, San Diego County, California; on the Sierra Nevada usually between altitudes of 2000° and 5000° and on the southern mountains rarely above 3000°; most abundant and of its largest size in the humid climate and rich soil of the bottom-lands of southwestern Oregon, forming extensive forests; in California usually much smaller, especially on the coast ranges.

Generally planted in the Pacific States for shade and as a street tree, and occasionally in the Eastern States as far north as Long Island, New York, and in western Europe; not hardy in Massachusetts.

6. Acer saccharum Marsh. Sugar Maple. Rock Maple.

Leaves rarely in whorls of 3, heart-shaped by a broad sinus, truncate or sometimes cuneate at base, 3—5-lobed, the lobes usually acute sparingly sinuate-toothed usually 3-lobulate at apex, with 3—5 conspicuous nerves, and reticulate veinlets, when they unfold coated below with pale pubescence, glabrous or more or less pubescent on the nerves below (var. _Schneckii_ Rehd.) and at maturity, 4′—5′ in diameter, often rather coriaceous, dark green and opaque on the upper surface, green or pale (var. _glabrum_ Sarg.) on the lower surface; turning in the autumn brilliant shades of deep red, scarlet and orange or clear yellow; petioles slender, glabrous, 1½—3′ in length. Flowers appearing with the leaves on slender more or less hairy pedicels ¾′—3′ long, in nearly sessile umbel-like corymbs from terminal leaf-buds and lateral leafless buds, the staminate and pistillate in the same or in separate clusters on the same or on different trees; calyx broad-campanulate, 5-lobed by the partial union of the obtuse sepals, greenish yellow, hairy on the outer surface; corolla 0; stamens 7—8, with slender glabrous filaments twice as long as the calyx in the staminate flower and much shorter in the pistillate flower; ovary obtusely lobed, pale green, covered with long scattered hairs, in the staminate flower reduced to a minute point; styles united at base only, with 2 long exserted stigmatic lobes. Fruit ripening in the autumn, glabrous, with broad thin and usually divergent wings ½′—1′ long; seeds smooth, bright red-brown, ¼′ long.

A tree, 100°—120° high, with a trunk often 3°—4° in diameter, rising sometimes in the forest to the height of 60°—70° without branches, or in open situations developing 8°—10° from the ground stout upright branches forming while the tree is young a narrow egg-shaped head, ultimately spreading into a broad round-topped dome often 70°—80° across, and slender glabrous branchlets green at first, becoming reddish brown by the end of their first season, lustrous, marked by numerous large pale oblong lenticels, and in their second winter pale brown tinged with red. Winter-buds acute, ¼′ long, with purple slightly puberulous outer scales, and inner scales becoming 1½′ long, narrow-obovate, short-pointed at apex, thin, pubescent, and bright canary yellow. Bark of young stems and of large branches pale, smooth or slightly fissured, becoming on large trunks ½′—¾′ thick and broken into deep longitudinal furrows, the light gray-brown surface separating into small plate-like scales. Wood heavy, hard, strong, close-grained, tough, light brown tinged with red, with thin sapwood of 30-40 layers of annual growth; largely used for the interior finish of buildings, especially for floors, in the manufacture of furniture, in turnery, shipbuilding, for shoe-lasts and pegs, and largely as fuel. Accidental forms with the grain curled and contorted, known as curly maple and bird’s-eye maple, are common and are highly prized in cabinet-making. The ashes of the wood are rich in alkali and yield large quantities of potash. Maple sugar is principally made from the sap of this tree.

Distribution. Newfoundland and Nova Scotia, westward to the Lake of the Woods, Ontario, and southward through eastern Canada and the northern states, and along the Appalachian Mountains to northern Georgia; in central Alabama and Mississippi, and westward in the United States to Minnesota, northeastern South Dakota (coulées of Little Minnesota River, Roberts County), central and northwestern Iowa, eastern Kansas, central Oklahoma, and eastern Louisiana; most abundant northward; ascending in North Carolina the Alleghany Mountains to altitudes of 3000°; the var. _glabrum_ rare and local in the north from Prince Edwards Island and Lake St. John, Quebec, to Iowa and southward to Pennsylvania, Ohio and central Tennessee; more abundant southward; apparently the only form but not common in South Carolina, Alabama, Mississippi, Louisiana and southern Arkansas; the var. _Schneckii_ with leaves glaucous or glaucescent below and more or less densely pubescent with spreading hairs, on the under side of the midrib and veins and on the petioles, southern Indiana and Illinois to western Kentucky and western and middle Tennessee, northwestern Georgia (near Rome, Floyd County), and to eastern Missouri southward to Williamsville, Wayne County.

Commonly planted as a shade and ornamental tree in the northern states.

More distinct are the following varieties:

Acer saccharum var. Rugelii Rehd.

Leaves thick, 3′—5′ long and 4′—6′ wide, pale and glabrous below, 3-lobed by broad rounded sinuses, rounded or slightly cordate at base, the lobes long-acuminate, usually entire, the middle lobe occasionally slightly undulate, the lateral lobes spreading, sometimes furnished near the base with a short acute lobule.

Distribution. Southeastern Ohio to western Pennsylvania (Kittaning, Armstrong County) and eastern and middle Tennessee, and to southern Ontario, the southern peninsula of Michigan, eastern and central Indiana, southern Illinois, eastern Missouri and northwestern Arkansas (Eureka Springs, Carroll County); rare and local in its extreme form; its 3-lobed leaves sometimes appearing on upper branches of trees bearing on lower branches leaves of the typical Sugar Maple.

Acer saccharum var. sinuosum Sarg.

_Acer sinuosum_ Rehd.

Leaves suborbicular, broader than long, 3—5-lobed with short triangular-ovate to triangular-oblong obtuse lobes, entire or on vigorous shoots occasionally dentate, usually broad-cordate at base, often with the nerves of the two lateral lobes projecting into the broad sinus and forming its base, when they unfold glabrous and purplish above, loosely hairy below, soon glabrous, and at maturity dark yellow-green and lustrous on the upper surface, pale, reticulate-venulose and glabrous except in the axils of the principal veins on the lower surface, 3—5-nerved, usually not more than 1½′ long, occasionally up to 2¾′ long and 3′ wide; petioles slender, glabrous, ½′—1½′ in length. Flowers appearing with the leaves, on slender glabrous pedicels, ½′—1¼ long, in 3—8-flowered nearly sessile corymbs; calyx broad-campanulate or cupulate, with short semiorbicular lobes ciliate on the margins; petals 0; stamens usually 6, with slender filaments longer than the calyx of the staminate flower; style divided to below the middle, with two spreading stigmas. Fruit glabrous, with long and broad almost horizontally spreading nutlets, convex, smooth, pale yellow-brown, the wing curved upward.

A tree, rarely more than 20° high with a short trunk 8′—10′ in diameter, small branches forming an open irregular head, and slender glabrous branchlets light green above when they first appear, becoming pale red-brown and marked by pale lenticels during their first season and ultimately dull gray-brown. Bark of the trunk smooth, pale gray. Winter-buds small, obtuse, covered with dark brown scales, those of the inner ranks accrescent, linear-oblong, scarlet or pink, up to 1⅛′ in length when fully grown.

Distribution. Edwards Plateau of western Texas, banks and bluffs of Cibolo Creek, near Boerne, Kendall County, on the rocky banks of upper Saco Creek, Bandera County, and at the base of a high limestone bluff near Utopia, Uvalde County; rare and local.

7. Acer floridanum Pax. Sugar Maple.

Leaves rounded, truncate or slightly cordate at the broad base, 3—5-lobed, with short obtuse or acute entire or lobulate lobes, when they unfold sparingly hairy on the upper surface and hoary-tomentose on the lower surface, and at maturity thin, dark green and lustrous above, pale or glaucescent and pubescent below, 1½′—3′ in diameter, and prominently 3—5-nerved, with stout spreading lateral veins and conspicuous reticulate veinlets; turning yellow and scarlet in the autumn before falling; petioles slender, glabrous, or pubescent generally becoming glabrous, 1½′—3′ in length, with an enlarged base nearly encircling the branchlet. Flowers appearing with the leaves on slender elongated sparingly hairy ultimately glabrous or villose-tomentose (var. _villipes_ Rehd.) pedicels, in many-flowered drooping nearly sessile corymbs; calyx campanulate, yellow, about ⅛′ long, persistent under the fruit, the short lobes ciliate on the margins with long pale hairs; corolla 0. Fruit green, sparingly villose until fully grown, usually becoming glabrous, with spreading occasionally erect wings ⅜′—¾′ long; seeds smooth, bright red-brown, about ¼′ long.

A tree, occasionally 50°—60° high, with a trunk rarely 3° in diameter, small erect and spreading branches, and slender glabrous or more or less densely villose-tomentose (var. _villipes_ Rehdr.) branchlets, light green when they first appear, becoming rather light red-brown during their first season, and covered with minute pale lenticels; usually smaller. Winter-buds obtuse, about ⅛′ long, with dark chestnut-brown obtuse scales and bright rose-colored linear-spatulate inner scales often 1′ long when fully grown. Bark of the trunk thin, smooth, pale, becoming near the base of old trees thick, dark, and deeply furrowed.

Distribution. River banks and low wet woods, southeastern Virginia (near McKinney, Dinwiddie County, _W. W. Ashe_), valley of the Roanoke River near Weldon, Halifax County, North Carolina, and southward to southern Georgia and western Florida to Lafayette County; near Selma, Dallas County, Alabama; West Feliciana Parish and through western Louisiana to eastern Texas (Harrison and St. Augustine Counties), and southern Arkansas (Fulton, Hempstead County); the var. _fillipes_ near Raleigh, Walker County, North Carolina, Calhoun Falls, Abbeville County, South Carolina, Shell Bluff on the Savannah River, Burke County, Cuthbert, Randolph County, and Columbus, Muscogee County, Georgia; River Junction, Gadsden County, Florida, and on the San Luis Mountains, southern New Mexico (_A. brachypterum_ Woot. & Stanl.).

Sometimes planted as a shade-tree; the prevailing tree in the streets and squares of Raleigh, North Carolina.

8. Acer grandidentatum Nutt. Sugar Maple.

Leaves cordate or truncate at base, 3-lobed by broad shallow sinuses, the lobes acute or obtuse, entire or slightly lobulate, sparingly hairy on the upper surface and thickly coated with dense pale tomentum on the lower surface when they unfold, and at maturity thick and firm, dark green and lustrous above, pale and pubescent below, especially on the stout nerves and veins, or rarely glabrous, 2′—5′ in diameter; turning in the autumn before falling yellow and scarlet; petioles stout, 1′—2′ in length, glabrous, often red after midsummer, encircling the branchlet with their large base villose on the inner surface. Flowers appearing with the leaves on long slender drooping villose pedicels, in short-stalked corymbs; calyx campanulate, yellow, sparingly hairy with long pale hairs, about ¼′ long, with broad rounded lobes, often persistent under the fruit; corolla 0; stamens 7 or 8, much longer than the calyx, in the pistillate flower shorter than the calyx; ovary usually glabrous, with long spreading stigmatic lobes, rudimentary in the staminate flower. Fruit often rose-colored at midsummer, green at maturity, glabrous or rarely sparingly hairy, with spreading or erect wings ½′—1′ long; seeds smooth, light red-brown, about ¼′ long.

A tree, occasionally 30°—40° high, with a trunk 8′—10′ in diameter, stout usually erect branches, and slender glabrous bright red branchlets marked by numerous small pale lenticels and nearly encircled by the narrow leaf-scars, with conspicuous bands of long pale hairs in their axils. Winter-buds acute or acuminate, about 1/16′ long, bright red-brown, with puberulous-ciliate outer scales and obovate apiculate inner scales sometimes ½′ long when fully grown. Bark of the trunk thin, dark brown, separating on the surface into plate-like scales. Wood heavy, hard, close-grained, bright brown or nearly white, with thick sapwood.

Distribution. Banks of mountain streams usually at altitudes of 5000°—6000° above the sea; on the Salt River Mountains, western Wyoming; valley of the Columbia River in northern Montana, southeastern Idaho (Pocatello, Oneida County), Wasatch Mountains, Utah, mountains of Arizona and of southern New Mexico; on the Guadalupe Mountains, western Texas, and on the Wichita Mountains, southwestern Oklahoma (_G. W. Stevens_); in Coahuila; rare and local.

Occasionally cultivated; hardy in the Arnold Arboretum.

9. Acer nigrum Michx. Black Maple.

Leaves generally 3 or occasionally 5-lobed, with abruptly short-pointed acute or acuminate lobes, undulate and narrowed from broad shallow sinuses and rarely furnished with short lateral spreading lobules, cordate at base with a broad sinus usually more or less closed by the approximation or imbrication of the basal lobes, occasionally 3-lobed with a broad long-acuminate nearly entire terminal lobe, and rounded or slightly cordate at base (var. _Palmeri_ Sarg.), covered below when they unfold with hoary tomentum and above with caducous pale hairs, and at maturity thick and firm in texture, dull green on the upper surface, yellow-green and soft-pubescent, especially along the yellow veins on the lower surface, and 5′—6′ long and wide, with drooping sides; turning bright clear yellow in the autumn; petioles stout, tomentose or pubescent, sometimes becoming glabrous at maturity, usually pendent, 3′—5′ in length, much enlarged at base, frequently nearly inclosing the buds, in falling leaving narrow scars almost encircling the branchlet and furnished in their axils with tufts of long pale hairs; stipules triangular and dentate or foliaceous, sessile or stipitate, oblong, acute, tomentose or pubescent, sometimes slightly lobed, frequently 1½′ long. Flowers yellow, about ¼′ long, on slender hairy pedicels 2½′—3′ long, in many-flowered nearly sessile umbel-like corymbs, the staminate and pistillate in separate or in the same cluster on the same or on different trees; calyx broad-campanulate, 5-lobed by the partial union of the sepals, pilose on the outer surface near the base; corolla 0; stamens 7 or 8, with slender glabrous filaments, in the staminate flower nearly twice as long as the calyx and in the pistillate flower shorter than the calyx; ovary obtusely lobed, pale green, covered with long scattered hairs, minute in the sterile flower. Fruit glabrous, with convergent or wide-spreading wings ½′—1′ long; seeds smooth, bright red-brown, ¼′ long.

A tree, sometimes 80° high, with a trunk frequently 3° in diameter, stout spreading or often erect branches, and stout branchlets marked by oblong pale lenticels, orange-green and pilose with scattered pale caducous hairs when they appear, orange or orange-brown and lustrous during their first year, becoming dull pale gray-brown the following season. Winter-buds sessile, ovoid, acute, ⅛′ long, with dark red-brown acute scales hoary-pubescent on the outer surface and often slightly ciliate on the margins, and yellow puberulous inner scales, ½′—1′ long at maturity. Bark of young stems and of the branches thin, smooth, pale gray, becoming on old trunks thick, deeply furrowed, and sometimes almost black.

Distribution. Valley of the St. Lawrence River in the neighborhood of Montreal, Quebec, southward to the valley of Cold River, New Hampshire, through western Vermont and Massachusetts and northwestern Connecticut (near Salisbury, Litchfield County), and westward through northern and western New York, southern Ontario, Ohio, the southern peninsula of Michigan, Indiana, Illinois, and Iowa to southeastern Minnesota, northeastern South Dakota, western and southern Missouri, eastern Kansas, and southward through western Pennsylvania, West Virginia and eastern Kentucky; comparatively rare near Montreal and in New England, more abundant farther west; almost entirely replacing _Acer saccharum_ in Iowa, and the only Sugar Maple of South Dakota; easily distinguished in summer by its heavy drooping leaves, and at all seasons of the year by the orange color of the branchlets; the var. _Palmeri_ in a single grove at Tunnel Hill, Johnson County, Illinois; southern Indiana (Shelby, Putnam and Lawrence Counties), and in Clark, Jackson and Dunklin Counties, Missouri; rare and local.