1. ACER L. Maple.
Characters of the family.
Acer with sixty or seventy species is widely distributed over the northern hemisphere, with a single species extending south of the equator to the mountains of Java. Acer produces light close-grained moderately hard wood valued for the interior finish of houses and in turnery. The bark is astringent, and the limpid sweet sap of some of the American species is manufactured into sugar.
Acer is the classical name of the Maple-tree.
CONSPECTUS OF THE NORTH AMERICAN ARBORESCENT SPECIES.
Leaves simple, usually palmately lobed (sometimes 3-foliolate in 1, 3-lobed at apex in 4). Flowers appearing with or after the leaves. Flowers with petals; sepals distinct. Inflorescence corymbose. Flowers in terminal drooping corymbs. Leaves 3-lobed or parted.1. [A. glabrum] (B, F, G). Leaves palmately 3—5-lobed.2. [A. circinatum] (B, G). Inflorescence racemose. Flowers in dense erect racemes.3. [A. spicatum] (A). Flowers in drooping racemes. Ovary and young fruit glabrous; leaves 3-lobed at apex.4. [A. pennsylvanicum] (A). Ovary and young fruit hairy; leaves deeply 5-lobed.5. [A. macrophyllum] (G). Flowers without petals; sepals united; inflorescence corymbose; pedicels long, pendulous, mostly hairy. Leaves pale or glaucescent, or green and glabrous beneath. Leaves green or pale beneath, glabrous or in one form villose-pubescent on the under side of the veins and on the petioles.6. [A. saccharum] (A, C). Leaves pale and pubescent, rarely glabrous beneath, their lobes usually short and obtuse or acuminate. Lobes of the leaves only slightly lobed or entire; bark of young trees smooth and pale.7. [A. floridanum] (C). Lobes of the leaves distinctly lobulate; bark of young trees dark brown and scaly.8. [A. grandidentatum] (F, H). Leaves green and pubescent, rarely glabrous beneath. Leaves hirsute-pubescent beneath and on the petioles, the lobes entire or lobulate, the basal sinus often closed by the lower lobes; bark dark and furrowed.9. [A. nigrum] (A). Leaves pilose-pubescent, rarely glabrous beneath, the lobes slightly lobulate, the basal sinus open; petioles glabrous; bark pale and smooth.10. [A. leucoderme] (C). Flowers appearing before the leaves in dense lateral clusters from separate buds; leaves 5-lobed (3-lobed in varieties of 12); fruit ripening in May or June. Flowers sessile or short-stalked, without petals; ovary and young fruit tomentose.11. [A. saccharinum] Flowers on long pedicels, with petals; ovary and young fruit glabrous.12. [A. rubrum] Leaves 3—7-foliolate; flowers diœcious, without petals.13. [A. Negundo] (A, B, C, F, G, H).
1. [Acer glabrum] Torr. Dwarf Maple.
Leaves glabrous, thin, rounded in outline, cordate-truncate or cuneate at base, 3—5-lobed, the middle lobe usually narrowed and entire below the middle, or often 3-parted or 3-foliolate (f. trisecta Sarg.), with acute or obtuse doubly serrate lobes, 3′—5′ in diameter, dark green and lustrous on the upper, paler on the lower surface, with conspicuous veinlets; petioles stout, grooved, 1′—6′ in length, and often bright red. Flowers about ⅛′ long on short slender pedicels, in loose few-flowered glabrous racemose corymbs on slender drooping peduncles from the end of 2-leaved branchlets, the staminate and pistillate usually produced separately on different plants; sepals oblong, obtuse, petaloid, as long as the greenish yellow petals; stamens 7 or 8, with glabrous unequal filaments shorter than the petals, much shorter or rudimentary in the pistillate flower; ovary glabrous, with short obtuse lobes, rudimentary or 0 in the staminate flower; style divided to the base into 2 spreading stigmatic lobes as long as the petals. Fruit glabrous, with broad nearly erect or slightly spreading wings ¾′—⅞′ long, often rose-colored during the summer; seeds ovoid, bright chestnut-brown, about ¼′ long.
A small tree, occasionally 20°—30° high, with a short trunk 6′—12′ in diameter, small upright branches, and slender glabrous branchlets often slightly many-angled, pale greenish brown when they first appear, becoming bright red-brown during their first winter; often a shrub. Winter-buds acute, ⅛′ long, with bright red or occasionally yellow scales, those of the inner ranks pale brown tinged with pink, tomentose on the inner surface, becoming 1½′ long and narrow-spatulate. Bark of the trunk thin, smooth, and dark reddish brown. Wood heavy, hard, close-grained, light brown or often nearly white, with thick lighter colored sapwood.
Distribution. Borders of mountain streams usually at elevations of 5000°—6000°; Rocky Mountains from Montana to Wyoming, the Black Hills of South Dakota, Sioux County, Nebraska, Colorado, Utah, Nevada, northern Arizona, and to the Sacramento Mountains, New Mexico; in California from the Siskiyou Mountains along the Sierra Nevada to the East Fork of the Kaweah River, Kern County, at altitudes of 5000°—6000° at the north and of 8000°—9000° at the south. Passing into
Acer glabrum var. Douglasii Dippel.
Acer Douglasii Hook.
Leaves ovate or oblong-ovate, slightly cordate by a wide shallow sinus, truncate or rarely rounded at base, 3-lobed with acuminate lobes often slightly divided into acuminate lobules, the terminal leaflet usually ovate from a broad base, or occasionally gradually narrowed below and rhombic in outline and sharply serrate to the base or nearly to the base of the lobe with long-acuminate teeth pointing forward, dark green above, paler and often glaucescent below, 3½′—4′ long and 3′—4′ wide, with 3 prominent nerves extending to the points of the lobes, and slender veins; petioles glabrous, 1′—3½′ in length. Flowers as in the species. Fruit with erect or nearly erect wings, ¾′—1′ long and ⅓′—½′ wide.
A tree, occasionally 40° high, with a short trunk 12′—18′ in diameter, small upright branches and slender bright red-brown branchlets.
Distribution. Coast of southern Alaska (head of Lynn Canal), southward near the coast to Vancouver Island and western Washington, and eastward on the high mountains of Washington to the Blue Mountains of eastern Oregon, western Idaho and northern Montana; on Loomis Creek, Natrona County, Wyoming.
2. [Acer circinatum] Pursh. Vine Maple.
Leaves almost circular in outline, cordate at base by a broad shallow sinus, or sometimes almost truncate, palmately 7—9-lobed occasionally nearly to the middle, with acute lobes sharply and irregularly doubly serrate, and conspicuously palmately nerved, with prominent veinlets, when they unfold tinged with rose color, and puberulous, especially on the lower surface and on the petioles, and at maturity glabrous with the exception of tufts of pale hairs in the axils of the large veins, thin and membranaceous, dark green above, pale below, and 2′—7′ in diameter; in the autumn turning orange and scarlet; petioles stout, grooved, 1′—2′ in length, clasping the stem by their large base. Flowers appearing when the leaves are about half grown, in loose 10—20-flowered umbel-like corymbs pendent on long stems from the end of slender 2-leaved branchlets, the staminate and pistillate flowers produced together; sepals oblong to obovate, acute, villose, purple or red, much longer than the greenish white broad, cordate petals folded together at apex; stamens 6-8, with slender filaments villose at base, exserted in the staminate flower, much shorter than the petals in the pistillate flower; ovary glabrous, with spreading lobes, in the staminate flower reduced to a small point surrounded by a tuft of pale hairs; style divided nearly to the base into long exserted stigmas. Fruit with thin wings, 1½′ long, spreading almost at right angles, red or rose color like the nutlets in early summer, ripening late in the autumn; seeds smooth, pale chestnut-brown, ⅛′¼′ long.
A tree, rarely 30°—40° high, often vine-like or prostrate, with a trunk 10′—12′ in diameter, and glabrous pale green or reddish brown branchlets frequently covered during their first winter with a glaucous bloom, and occasionally marked by small lenticels; often a low wide-spreading shrub. Winter-buds ⅛′ long, rather obtuse, with thin bright red outer scales rounded on the back, and obovate-spatulate inner scales rounded at apex, contracted into a long narrow claw, bright rose-colored and more or less pubescent, especially on the outer surface, and when fully grown often 2′ long and ¼′ broad. Bark of the trunk thin, smooth, bright red-brown, marked by numerous shallow fissures. Wood heavy, hard, close-grained, not strong, light brown, sometimes nearly white, with thick lighter colored sapwood; used for fuel, the handles of axes and other tools, and by the Indians of the northwest coast for the bows of their fishing-nets.
Distribution. Banks of streams; coast of British Columbia through western Washington and Oregon to Mendocino County, and the cañon of the upper Sacramento River, California; one of the most abundant of the deciduous-leaved trees of western Washington and Oregon up to altitudes of 4000° above the sea, and of its largest size on the rich alluvial soil of bottom-lands, its vine-like stems in such situations springing 4 or 5 together from the ground, spreading in wide curves and sending out long slender branches rooting when they touch the ground and forming impenetrable thickets of contorted and interlaced trunks, often many acres in extent; in California smaller and less abundant, growing along streams in the coniferous forest or rarely on dry ridges up to an altitude of 4000° in the northeastern part of the state.
Occasionally cultivated as an ornamental plant in Europe, and in the eastern states, and hardy as far north as eastern Massachusetts.
3. [Acer spicatum] Lam. Mountain Maple.
Leaves subcordate or sometimes truncate at base, conspicuously 3-nerved, 3 or slightly 5-lobed, with gradually narrowed pointed lobes, and sharply and coarsely glandular-serrate, when they unfold puberulous on the upper surface and densely tomentose on the lower surface, and at maturity thin, 4′—5′ long and broad; turning in the autumn to various shades of orange and scarlet; petioles slender, enlarged at base, 2′—3′ in length, often becoming scarlet in summer. Flowers opening in June after the leaves are fully grown, ¼′ diameter, on slender pedicels ½′—¾′ long, the pistillate toward the base and the staminate at the apex of a narrow many-flowered long-stemmed upright slightly compound pubescent raceme; calyx-lobes narrow-obovate, yellow, pubescent on the outer surface, much shorter than the linear-spatulate pointed yellow petals; stamens 7 or 8, inserted immediately under the ovary, with slender glabrous filaments as long as the petals in the sterile flower, about as long as the sepals in the pistillate flower, and glandular anthers; ovary hoary-tomentose, reduced to a minute point surrounded by a tuft of pale hairs in the staminate flower; style columnar, almost as long as the petals, with short stigmatic lobes. Fruit fully grown and bright red or yellow in July, turning brown late in the autumn, almost glabrous, with more or less divergent wings about ½′ long; seeds smooth, dark red-brown, ⅛′ long.
A bushy tree, occasionally 25°—30° high, with a short trunk 6′—8′ in diameter, small upright branches, and slender branchlets light gray and pubescent when they first appear, becoming glabrous during the summer, bright red during their first winter, gray or pale brown the following season, and blotched or streaked with green toward the base; more often a tall or low shrub. Winter-buds acute; the terminal ⅛′ long, with bright red outer scales more or less coated with hoary tomentum, those of the inner ranks becoming at maturity 1′ or more in length and then lanceolate, pale and papery; axillary buds much smaller and glabrous or puberulous. Bark of the trunk very thin, reddish brown, smooth or slightly furrowed. Wood light, soft, close-grained, light brown tinged with red, with thick lighter colored sapwood.
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.
Occasionally planted in the region where it grows naturally as a shade-tree.
10. [Acer leucoderme] Small. Sugar Maple.
Leaves usually truncate or slightly cordate at base, more or less deeply divided into 3—5 acute caudate-acuminate lobes coarsely and sinuately dentate or undulate, when they unfold coated below with long matted pale caducous hairs, and at maturity thin, dark yellow-green above, bright yellow-green and pilose-pubescent below, 2′—3½′ in diameter; often turning in the autumn bright scarlet on the upper surface before falling; petioles slender, glabrous, 1′—1½′ in length. Flowers yellow, about ⅛′ long, on slender, glabrous pedicels, in nearly sessile clusters; calyx campanulate, glabrous or slightly villose, with rounded ciliate lobes; corolla 0; stamens 7 or 8; filaments villose, longer than the calyx, much shorter than the calyx in the pistillate flower; ovary villose; style elongated, with short spreading lobes. Fruit villose, with long scattered pale hairs until nearly grown, becoming glabrous at maturity, the wings wide-spreading or divergent, ½′—¾′ long; seeds smooth, light red-brown, about ¼′ long.
A tree, usually 20°—25° high, with a trunk a foot in diameter, occasionally 40° high, with a trunk 18′—20′ in diameter, short slender branches forming a rather compact round-topped head, and slender glabrous branchlets dark green when they first appear, becoming bright red-brown and lustrous during their first summer, and marked by numerous small oblong pale lenticels, gradually growing darker in their second year and finally light gray-green. Winter-buds ovoid, acute, dark brown, glabrous, rather more than 1/16′ long, the inner scales becoming bright crimson and very conspicuous when the tree is in flower. Bark of young stems and large branches close, light gray or grayish brown, becoming near the base of old trees dark brown or often nearly black and broken by deep furrows into narrow ridges covered by closely appressed scales.
Distribution. Banks of streams, rocky gorges, and woods in moist soil; valley of the Yadkin River, Stanley County, North Carolina; southeastern Tennessee (Polk County); valley of the Savannah River (Abbeville County, South Carolina, and Richmond County, Georgia) to central and northwestern Georgia (near Rome, Floyd County, and Walker County) and to the valley of the Chattahoochee River to Muscogee County; northern and central Alabama; western Louisiana (Natchitoches and Sabine Parishes); southern Arkansas (Baker Springs, Howard County); rare and local; most abundant in northwestern and central Georgia and northern Alabama.
Occasionally planted as a street tree in the towns of northern Georgia and Alabama; hardy as far north as eastern Massachusetts.
11. [Acer saccharinum] L. Silver Maple. Soft Maple.
Leaves truncate or somewhat cordate at base, deeply 5-lobed by narrow sinuses, with acute irregularly and remotely dentate lobes, the middle lobe often 3-lobed, 6′—7′ long and nearly as broad, thin, bright pale green above, silvery white and at first slightly hairy below, especially in the axils of the primary veins; turning pale yellow in the autumn before falling; petioles slender, drooping, bright red, 4′—5′ in length. Flowers greenish yellow, opening during the first warm days of the late winter or early spring long before the appearance of the leaves, on short pedicels, in sessile axillary fascicles on shoots of the previous year, or on short spur-like branchlets developed the year before from wood of the preceding season, the staminate and pistillate in separate clusters, on the same or on different trees, and produced from clustered obtuse buds covered with thick ovate pubescent red and green scales ciliate on the margins with a thick fringe of long rufous hairs; calyx slightly 5-lobed, more or less pubescent on the outer surface, long and narrow in the staminate and short and broad in the pistillate flower; corolla 0; stamens 3—7, with slender filaments, three times as long as the calyx of the staminate flower and about as long as the calyx of the pistillate flower; ovary covered, like the young fruit, with a thick coat of pubescence, rudimentary in the sterile flower; styles united at base only, with long exserted stigmatic lobes. Fruit ripening in April and May when the leaves are nearly grown, on slender drooping pedicels, 1½′—2′ long, glabrous, 1½′ to nearly 3′ long, with thin almost straight conspicuously falcate divergent wings sometimes ¾′ broad, prominently reticulate-veined and pale chestnut-brown or rarely bright red; seeds ½′ long, with a pale reddish brown wrinkled coat, germinating as soon as they fall to the ground, and producing plants with several pairs of leaves before the end of the summer.
A tree, 90°—120° high, with a trunk 3°—4° in diameter, generally dividing 10°—15° from the ground into 3 or 4 stout upright secondary stems destitute of branches for a considerable length, brittle pendulous branchlets light green and covered with lenticels when they first appear, soon becoming darker, bright chestnut-brown, smooth and lustrous in the autumn and winter of their first year, and in their second season pale rose color or gray faintly tinged with red. Winter-buds ⅛′ long, with thick ovate bright red outer scales rounded on the back, minutely apiculate, and ciliate on the margins, and acute inner scales pubescent on the inner surface, becoming pale green or yellow and about 1′ long. Bark of young stems and large branches smooth and gray faintly tinged with red, becoming on old trunks ½′—¾′ thick, reddish brown and more or less furrowed, the surface separating into large thin scales. Wood hard, strong, close-grained, easily worked, rather brittle, pale brown, with thick sapwood of 40—50 layers of annual growth; now sometimes used for flooring and in the manufacture of furniture. Sugar is occasionally made from the sap.
Distribution. Sandy banks of streams, rarely in deep often submerged swamps; valley of the St. John’s River (near Fredericton), New Brunswick, to that of the St. Lawrence in Quebec, and southward through western Vermont and central Massachusetts to western Florida, Alabama, and south central Mississippi, and westward through Ontario, New York, Ohio, the southern peninsula of Michigan and southern Indiana to Minnesota, southeastern South Dakota, and eastern Nebraska, and through Kentucky, Tennessee, Missouri, eastern Kansas, northwestern Arkansas, and eastern Oklahoma; in western Louisiana (swamp near Alexandria, Rapides Parish); rare in the immediate neighborhood of the Atlantic coast and on the high Appalachian Mountains; probably of its largest size in the valley of the lower Ohio River.
Often cultivated with several forms differing in habit and in the lobing of the leaves; fast-growing, and largely planted in the eastern states as a park and street tree.
12. [Acer rubrum] L. Red Maple. Scarlet Maple.
Leaves truncate, more or less cordate by a broad shallow sinus, rounded or cuneate at base, 3—5-lobed by acute sinuses, with irregularly doubly serrate or toothed lobes, the middle lobe often longer than the others, when they unfold pubescent especially beneath, and at maturity light green and glabrous on the upper surface and white or glaucescent and more or less pubescent or densely tomentose (var. tomentosum Kirch. [var. rubrocarpum Detmars]) on the lower surface, particularly along the principal veins, chartaceous or sometimes almost coriaceous, 1½′—6′ long and rather longer than broad; turning in the early autumn to brilliant shades of scarlet and orange, or clear bright yellow; petioles slender, glabrous or puberulous, red or green, 2′—4′ in length. Flowers opening in March and April before the appearance of the leaves, bright scarlet, dull yellowish red or sometimes yellow (var. pallidiflorum Pax.), on long slender pedicels, in few-flowered fascicles on branches of the previous year, from clustered obtuse buds, the staminate and pistillate flowers in separate clusters on the same or on different trees; sepals oblong, obtuse, as long as and broader than the oblong or linear petals; stamens 5—8, scarlet or yellow, with slender filaments exserted in the staminate and included in the pistillate flower; ovary glabrous on a narrow slightly lobed glandular disk; styles slightly united above the base, with long exserted stigmatic lobes. Fruit ripening in the spring or early summer on drooping stems 3′—4′ long, scarlet, dark red or brown or yellow, with thin erect wings, convergent at first, divergent at maturity, ½′—1′ long and ¼′—½′ wide; seeds dark red, with a rugose coat, ¼′ long, germinating as soon as it falls to the ground.
A tree, 80°—120° high, with a tall trunk 3°—4½° in diameter, upright branches usually forming a rather narrow head, and branchlets green or dark red when they first appear, becoming dark or bright red and lustrous at the end of their first summer and marked by numerous longitudinal white lenticels, and gray faintly tinged with red in their second year. Winter-buds obtuse, ⅛′ long, with thick dark red outer scales, rounded on the back and ciliate on the margins, and inner scales becoming ¾′—1′ long, narrow-oblong, rounded at apex and bright scarlet. Bark of young stems and of the branches smooth and light gray, becoming on old trunks ¼′—½′ thick, dark gray, and divided by longitudinal ridges separating on the surface into large plate-like scales. Wood very heavy, close-grained, not strong, light brown often slightly tinged with red, with thick rather lighter colored sapwood; used in large quantities in the manufacture of chairs and other furniture, in turnery, for wooden ware and gun-stocks.
Distribution. Borders of streams, wet swamps, upland forests and rarely on dry rocky hillsides and sand dunes; Newfoundland, southward to southern Florida (banks of the Miami River, Dade County, on the east coast and to Cypress swamps east of Everglade, Lee County, on the west coast) and westward through Quebec to latitude 49° north, and Ontario to the sandy shores of the Upper Peninsula of Michigan (Brevort, Mackinac County, on Lake Michigan and White Fish Point, Chippewa County, on Lake Superior), western Wisconsin, northwestern Minnesota (Buckeye County), southeastern Iowa (Johnson County), central Oklahoma, and the valley of the Trinity River, Texas; on the mountains of North Carolina to altitudes of 4500°; one of the commonest and most generally distributed trees of eastern North America, ranging between more degrees of latitude than any other American tree; most abundant southward especially in the valley of the Mississippi River, and of its largest size in the river swamps of the lower Ohio and its tributaries; in the north often covering with small trees low wet swamps; on the sand dunes and ridges of northern Michigan reduced to a low shrub. On var. tomentosum leaves usually 5-lobed, cordate or rarely rounded at base, with glabrous or pubescent petioles and branchlets; widely distributed but rare; near Cranberry Island, Buckeye Lake, Licking County, Ohio; Biltmore, Buncombe County, North Carolina; neighborhood of Augusta, Richmond County, Georgia; top of Flagstaff Mountain, Barclay, Talladega County, Alabama; Panther Burn, Sharkey County, Mississippi; near Little Rock, Pulaski County, Arkansas; near Page, Leflore County, Oklahoma, and Larissa, Cherokee County, Texas; connected by trees of this variety with pubescent branchlets and winter-buds, and broad-ovate 3—5-lobed slightly cordate leaves and pubescent petioles with
Acer rubrum var. Drummondii Sarg.
Leaves often broader than long, usually 5-lobed, cordate or truncate at base, 3′—6′ long and wide, with a stout midrib and veins, until nearly fully grown covered above with scattered hairs and clothed below with thick snow-white tomentum, and more or less pubescent during the season; petioles stout, hoary-tomentose, 1¼′—4′ in length, becoming nearly glabrous in the autumn. Flowers bright scarlet. Fruit ripening with or before the unfolding of the leaves late in March or in April, bright scarlet, with convergent wings 1¼′—2½′ long and ½′—¾′ wide.
A tree, usually not more than 30°—35° high, with small erect branches forming a narrow head and slender branchlets coated when they first appear with matted pale hairs, becoming glabrous and dark reddish brown in their second season.
Distribution. Deep swamps, eastern Louisiana to the valley of the Neches River (Beaumont, Jefferson County, and Concord, Hardin County), eastern Texas and northward through southern and eastern Arkansas to western Mississippi, western Tennessee and Kentucky, southeastern Missouri (Butler, Stoddard, Dunklin and Mississippi Counties), southern Illinois (Gallatin, Pulaski and Richland Counties), and southwestern Indiana (swamp eighteen miles west of Decker, Knox County, C. C. Deam). A form growing at Hattiesburg, Forrest County, Mississippi, at Glen Gordon, Covington, St. Tammany Parish, and Chopin, Natchitoches Parish, Louisiana, near Beaumont, Jefferson County, Texas, and at Poplar Bluff, Butler County, Missouri, with 3-lobed leaves rounded at base (f. rotundatum Sarg.) shows in the shape of the leaves a transition from the var. Drummondii to
Acer rubrum var. tridens Wood. Red Maple.
Acer carolinianum Britt., not Walt.
Leaves obovate, usually narrowed from above the middle to the rounded or rarely cuneate base, 3-lobed at apex, with acute or acuminate erect or slightly spreading lobes, simple or furnished with short lateral secondary lobes, remotely serrate except toward the base, with incurved glandular teeth, and often ovate by the suppression of the lateral lobes and acute or acuminate, thick and firm in texture, glaucous and usually pubescent or rarely tomentose or tomentulose below, 2′—3′ long and 1½′—2½′ wide; petioles slender, glabrous or pubescent. Flowers sometimes tawny yellow. Fruit usually much smaller and rarely also yellow.
Distribution. Usually with the species; Massachusetts and central New York, southward usually in the coast region and the middle districts to western Florida, along the Gulf coast to the valley of the Trinity River, Texas, and through western Louisiana, and Arkansas to northeastern Mississippi, southern Missouri, western Tennessee and Kentucky and southern Illinois; in North Carolina occasionally ascending on the Appalachian Mountains to altitudes of 3000°; often the prevailing Red Maple in southern Missouri and northwestern Louisiana; in the swamps of western Florida and southwestern Georgia the form with leaves densely tomentose below and pubescent petioles prevails.
13. [Acer Negundo] L. Box Elder. Ash-leaved Maple.
Leaves usually 3, rarely 5—7-foliolate, with a slender glabrous petiole 2′—3′ in length, the enlarged base often furnished with a minute rim of deciduous white hairs, and in falling leaving a large conspicuous scar surrounding the stem; leaflets ovate to elliptic or obovate, acuminate, and often long-pointed at apex, rounded or cuneate and often unsymmetrical at base, coarsely and irregularly serrate usually only above the middle or nearly entire, and occasionally slightly and irregularly lobulate; when they unfold more or less hoary-tomentose below and slightly pubescent above, and at maturity thin, light green, paler on the lower than on the upper surface, glabrous above, villose-pubescent along the under side of the midrib and veins, often furnished with conspicuous tufts of axillary hairs, otherwise glabrous or slightly pubescent below, 2½′—4′ long, and 1½′—2½′ wide, on slender glabrous petiolules, that of the terminal leaflet ¾′—1′ long and much longer than those of the smaller lateral leaflets. Flowers on slender glabrous or rarely hairy pedicels, minute, apetalous, yellow-green, the staminate and pistillate on separate trees, expanding just before or with the leaves from buds developed in the axils of the last leaves of the previous year, the staminate fascicled, the pistillate in narrow drooping racemes, sometimes furnished near the base with one or two smaller 3-lobed or rarely elliptic leaves; calyx 5-lobed, hairy, campanulate in the staminate flower, much smaller in the pistillate flower and divided to the base into 5 narrow sepals; corolla 0; stamens 4—6, with slender exserted hairy filaments and long linear anthers narrowed and apiculate at apex, 0 in the pistillate flower; ovary on a narrow rudimentary disk, pubescent, only partly inclosed by the calyx; style separating from the base into 2 long stigmatic lobes. Fruit attaining nearly its full size in summer, pendent on glabrous stems 1′—2′ long, in graceful racemes 6′—8′ in length, ripening in the autumn, deciduous from the stems persistent on the branches until the following spring, 1½′—2′ long, with narrow acute pubescent nutlets diverging at an acute angle and constricted below into a stipe-like base, and thin reticulate straight or falcate wings undulate toward the apex; seeds narrowed at the ends, smooth, bright red-brown, ½′ long.
A tree 50°—70° high, with a trunk 2°—4° in diameter, dividing near the ground into a number of stout wide-spreading or erect branches, and slender pale green lustrous glabrous branchlets. Winter-buds terminal acute, ⅛′ long, rather longer than the obtuse lateral buds, the scales tomentose, those of the inner pairs accrescent, becoming 1′ long at maturity, deciduous, leaving conspicuous scars visible at the base of the branchlet for two or three years. Bark of the trunk ¼′—½′ thick, pale gray or light brown and deeply divided into broad rounded ridges separating on the surface into short thick scales. Wood light, soft, close-grained, not strong, creamy white, with thick hardly distinguishable sapwood; occasionally manufactured into cheap furniture, and sometimes used for the interior finish of houses, for wooden ware, cooperage, and paper pulp. Small quantities of maple sugar are occasionally made from this tree.
Distribution. Banks of streams and lakes, and the borders of swamps; western Vermont, western Massachusetts and Connecticut, central New York and southwestern Ontario, and southward to west-central Florida (Hernando County) and westward to Minnesota, Iowa, Nebraska, Missouri, eastern Kansas, Arkansas, eastern Oklahoma, western Louisiana, and eastern and southern Texas to the valley of the lower Rio Blanco.
Often planted in the United States, especially in the western states and in eastern Canada, and in western and northern Europe, especially the varieties with variegated leaves.
Passing into the following varieties:
Var. violaceum Kirch., with slender pale or bluish violet glabrous branchlets covered with a glaucous bloom and rather larger winter-buds. Leaves 3—11, usually 3—7-foliolulate, the leaflets slightly thicker, lanceolate to oblong-ovate or obovate, often entire or irregularly dentate, occasionally lobed, the terminal leaflet sometimes 3-lobed, usually pubescent and furnished with tufts of axillary hairs on the lower surface. Fruit glabrous, usually constricted at the base. Western Massachusetts through Ohio to northern Wisconsin, Minnesota, Iowa and South Dakota, and to northern and southwestern Missouri; in Nez Perces County, Idaho.
Var. texanum Pax., with branchlets covered with pale tomentum. Leaves 3-foliate, the leaflets ovate, or the terminal obovate, acuminate, short-pointed at apex, rounded or cuneate at base, coarsely serrate above the middle or entire, only slightly and irregularly lobed, early in the season villose along the midrib and veins above and thickly coated below with matted pale hairs, and at maturity nearly glabrous on the upper surface and covered below with loose pubescence, 3′—4′ long and 2′—3′ wide. Fruit puberulous, constricted into a short stipe-like base. Western and southwestern Missouri, southeastern Kansas, Arkansas, Oklahoma and eastern Texas to the valley of the San Antonio River. Passing into forma latifolia Sarg. differing only in its glabrous branchlets, and distributed from eastern Texas through Louisiana to western Mississippi, western North Carolina, Virginia and southern Ohio.
Var. interior Sarg., with branchlets covered with close pale pubescence, or rarely nearly glabrous. Leaves trifoliate, with puberulous petioles, rachis and petiolules, the long-stalked leaflets ovate to lanceolate, or the terminal sometimes obovate, acuminate and long-pointed at apex, cuneate, rounded or cordate at base, coarsely serrate, sometimes distinctly 3-lobed at base, glabrous or villose on the midrib below, or in Arizona sometimes sparingly pubescent on the lower surface, 3′—4′ long and 1½′—4′ wide. Fruit glabrous, not at all, slightly or at the north conspicuously constricted at the base. Southern Manitoba, Saskatchewan and Alberta to Wyoming, and through the mountain regions of Colorado and Utah to New Mexico and Arizona.
Var. arizonicum Sarg., with glabrous branchlets thickly covered with a glaucous bloom. Leaves thin, 3-foliolulate; petioles slender, glabrous, 1¾′—3′ long, often turning bright red late in summer; leaflets oblong-ovate to rhombic, acuminate and long-pointed at apex, rounded or cuneate at base, coarsely serrate, often slightly lobed near the middle, glabrous with the exception of conspicuous tufts of axillary hairs, 2½′—4′ long, 1½′—2′ wide; petiolules slender, glabrous, usually bright red, that of the terminal leaflet ¾′—1′ long, the others not more than ⅛′ in length. Fruit in glabrous racemes 3′ or 4′ long, the body glabrous, spreading, not constricted at base. A tree, 20°—25° high. Bark fissured. Mountain cañons, central and southern Arizona up to 8000° altitude, and in Socorro County, New Mexico. More distinct is
Acer Negundo var. californicum Sarg.
Leaves trifoliate with tomentose or nearly glabrous rachis and petiolules; leaflets oblong-ovate to rhombic, acuminate and long-pointed at apex, cuneate or unsymmetrically rounded at base, coarsely serrate above the middle, or nearly entire, when they unfold hoary-tomentose below and densely pubescent above, occasionally deeply lobed, glabrous on the upper surface except along the midrib and veins, thickly coated on the lower surface with matted pale hairs and furnished with large axillary tufts. Fruit on pubescent pedicels, puberulous or nearly glabrous, not constricted or rarely slightly constricted at base.
A tree, 20°—50° high, with dark bark, hoary-tomentose branchlets and winter-buds.
Distribution. California, valley of the lower Sacramento River and the interior valleys of the coast ranges from the Bay of San Francisco to Santa Barbara County and in elevated cañons on the western slopes of the San Bernardino Mountains; widely distributed but nowhere abundant.
Occasionally planted in California.