Plant: tree; to ca. 12 m high, mainly glabrous to subglabrous except for finely pubescent lower leaf surfaces and young growth; young twigs yellowish-brown, soon becoming chestnut-brown and essentially glabrous; buds at maturity with 3 or 4 series of dark brown, imbricate scales, these pubescent within, elongating when buds break

Leaves: suborbicular in outline, palmately 3-lobed (2 additional basal lobes sometimes present), 3-8.5 cm long, 4-12 cm wide, discolorous, the major lobes in turn with up to ca. 5 weak lobes or teeth; apex of leaf and lateral lobes bluntly acute; base cordate to subcordate; petiole glabrous or pubescent distally; margin sinuate to irregularly dentate or lobed

INFLORESCENCE: inflorescence corymbose

Flowers: to ca. 10 mm long, 1.5-3 mm wide at base of perianth, the usually cup-like perianth greenish-yellow, ca. 5 mm long, sometimes splitting to base, the receptacle truncate to obconic, the perianth margin sinuate to shallowly lobed; the pedicel 1-5 cm long

Fruit: samaras 2.2-5 cm long, the wing 0.7-1.5 cm wide

Misc: In conifer forests or in wet areas in oak forests; 1350-2600 m (4500-8500 ft); Apr-May (retaining fruits until about Sep)

REFERENCES: Landrum, Leslie R. 1995. Aceraceae. J. Ariz. - Nev. Acad. Sci. 29(1): 2, 2-3.

Common Name: bigtooth maple

Duration: Perennial

Nativity: Native

Lifeform: Tree

Wetland Status: FACU

General: Trees up to 15 m, with smooth gray or brown bark.

Leaves: Leaves thick and pubescent below, palmately divided, with few, obtuse teeth, mostly sessile or borne on short petioles, the margin sinuate to irregularly dentate or lobed.

Flowers: Borne in clusters, bright green, small and rounded, about 10 mm long, 1.5-3 mm wide at base, cup-like perianth made up of inconspicuous petals that are greenish yellow, borne on pedicels 1-5 cm long, with numerous, exserted stamens.

Fruits: Winged samaras with 2 large fruits, fused in the middle, 2-5 cm long and 1-1.5 cm wide, bright green when young, turning reddish with age, and then to light tan at maturity.

Ecology: Found in canyons and coniferous forests from 4,500-7,000 ft (1372-2134 m); flowers in April.

Distribution: Ranges north to Idaho and Wyoming and south to Guatemala.

Notes: This is the classic-looking maple, with big-toothed leaves, turning a bright, lovely red in fall.

Ethnobotany: Unknown

Etymology: Acer is the classical Latin name for the maple genus, while grandidentatum means bearing large teeth.

Synonyms: Acer grandidentata

Editor: LCrumbacher, 2011