Plant: shrubs and trees Stem: sometimes with milky and/or sugary sap (stems or stems and leaves); buds opposite Root: Leaves: deciduous; opposite, mostly simple and toothed, with petioles, palamately lobed or more rarely pinnately compound; pinnately or palmately veined; no stipules Flowers: perfect or more often imperfect (monoecious or dioecious); usually regular (actinomorphic), small and in clusters, 4-6 but mostly 5 colored sepals; 4-6 but mostly 5 petals or absent (rare); 4-12 but mostly 8 stamens; ovary superior,1 pistil, 2 stigmas and styles, 2-3 fused carpels Fruit: schizocarp - doubled, rarely tripled samaras in Acer , 1-seeded, flat and long winged in Acer and rounded in Dipteronia Other: most are maples in N.A. + box elders; opposite and lobed leaves, usually sharp-toothed, some Viburnum shrubs have maple-like leaves and the box elders have opposite compound leaves, several cultivated varieties; Dicotyledons Group Genera: Acer (maple), (Dipteronia in China)
WARNING – family descriptions are only a layman’s guide and should not be used as definitive COMMON NATIVE Leaves opposite and lobed except for Ash-Leaf Maple (Box- Elder) with opposite compound leaves; samaras double-winged; MAPLE LEAVES flowers small in most species
Silver Maple Sugar Maple
Box-Elder [Ash-Leaved Maple]
leaves with 5 deep lobes, leaves a paler green and 5-lobed with terminal lobe somewhat sharp teeth, edges firm (don’t droop), narrowed at base, sinuses U- sinuses of moderate depth and u- shaped, leaf whitened below shaped, mostly smooth beneath and sometimes hairy
Black Maple leaves 3-5 lobed, base of terminal lobe wide, sinuses shallow and V- 3-5(7) lobes, sinuses deep shaped, whitened and and rounded, leaf edge often +/- hairy beneath rolled downward at margins, green beneath, little or no basal sinus, petioles thicken Red Maple at base COMMON INTRODUCED MAPLE LEAVES
Norway Maple Leaves 3-5(-7) lobed, teeth sharp and long pointed, sinuses rounded, bright green above and below
Amur Maple leaves with 3 pointed lobes, middle lobe much longer than lateral lobes, margins well Several other species are also toothed, bright green above and paler below cultivated as ornamentals - Japanese Maple (A. palmatum), Sycamore Maple (A. pseudoplatanus) and others. ACERACEAE – MAPLE FAMILY
Amur maple; Acer ginnala Maxim. (Introduced) Boxelder [Ash-Leaved Maple]; Acer negundo L. var. negundo Black Maple; Acer nigrum Michx. f. Norway Maple; Acer platanoides L. (Introduced) Silver [Soft] Maple; Acer saccharinum L. Sugar [Hard] Maple; Acer saccharum Marsh. var. saccharum Red Maple; Acer rubrum L. var. rubrum Amur maple USDA Acer ginnala Maxim. (Introduced) Aceraceae (Maple Family) Oak Openings Metropark, Lucas County, Ohio Notes: tree; flowers dioecious, small, yellow to white, 4-5 petals, clustered at end of branches; leaves simple, opposite, toothed, 3-lobed with middle lobe considerably longer, lobes pointed, bright green above, somewhat paler green below; bark dark gray to brown, somewhat thin, shallow fissures and plates; twigs light brown to yellowish brown, slender; terminal buds rounded at base, pointed at tip; fruit a samara, up to 1 in; spring (widely cultivated, from Asia) [V Max Brown, 2009] Box-Elder [Ash-Leaved Maple] USDA Acer negundo L. var. negundo Aceraceae (Maple Family) University of Toledo Campus, Lucas County, Ohio Notes: shrubs and trees; flowers in clusters (dioecious); leaves opposite, compound (3-5(7)), usually a few coarse teeth; bark smooth but is furrowed with age; twigs smooth, bright green or purple and glaucous; winter buds white-hairy, 3-5 bundle scars; fruit of dangling clusters of samaras that often over winter on pistillate trees; spring [V Max Brown, 2005]
winter
Staminate flowers Black Maple USDA Acer nigrum Michx. f. Aceraceae (Maple Family) Maumee River Metroparks, Lucas County, Ohio Notes: tree; flowers small, monoecious; leaves with 3-5(7) lobes, sinuses rounded, leaf edge often rolled downward at margins, green beneath, little or no basal sinus, petioles thicken at base and partially enclose buds; bark somewhat dark, grooved when old; twigs a dull orange-brownish; terminal bud small, lower scales not hairy, dark in color; fruit a samara ripening late summer; spring [V Max Brown, 2005] Norway Maple USDA Acer platanoides L. (Introduced) Aceraceae (Maple Family) Oak Openings Metropark, Lucas County, Ohio Notes: tree; flowers dioecious, large, yellow, 5 petals and sepals, in flat raceme, often flowering before leaves; leaves simple, large, palmately 3-5(-7) lobed, teeth sharp and long pointed, sinuses rounded, bright green above and below; bark dark gray, somewhat thin, shallow fissures and ridges; twigs light brown and shiny to somewhat greenish; terminal buds large, reddish, blunt or rounded tip with 2-3 scale pairs, side buds small; fruit a samara, almost 180˚ divergent; spring [V Max Brown, 2008] Silver [Soft] Maple USDA Acer saccharinum L. Aceraceae (Maple Family) Maumee River Metroparks, Lucas County, Ohio Notes: tree; flowers small, monoecious, usually red; leaves with 5 deep lobes, terminal lobe somewhat narrowed at base, sinuses U-shaped, leaf whitened below and sometimes hairy; bark grayish, smooth when young and somewhat flaky with age; twigs reddish with bad odor when broken; buds reddish and blunt; fruit a samara, often greenish to red, spring [V Max Brown, 2005] Sugar [Hard] Maple USDA male female Acer saccharum Marsh. var. saccharum Aceraceae (Maple Family) Oak Openings Metropark, Lucas County, Ohio Notes: tree; flowers small, monoecious or dioecious, yellow; leaves pale green and 5-lobed with sharp teeth, edges firm (don’t droop), sinuses of moderate depth and u-shaped (mostly less than 90°), mostly smooth beneath; bark smooth but grooved with loose plates on older bark; twigs red- brown, glossy; buds pointed, slender, side buds in pairs; fruit a samara, spring [V Max Brown, 2005] Red Maple USDA Acer rubrum L. var. rubrum Aceraceae (Maple Family) Oak Openings Metropark, Lucas County, Ohio Notes: tree; flowers monoecious or dioecious, mostly red (sometimes yellow); leaves 3-5 lobed, base of terminal lobe wide, sinuses shallow and V-shaped, whitened and mostly glabrous beneath; bark rough and flaky when old, smooth when young; twigs reddish; buds reddish, blunt, with several scales; fruit a samara; spring [V Max Brown, 2005]