Northern Ontario Plant Database
Acer rubrum L.
En: red maple, scarlet maple, soft maple, swamp maple
Sapindaceae (Soapberry Family)
General: A medium-sized hardwood tree, to 25 m tall, with spreading to ascending branches; young twigs red and shiny; trunk usually branch-free for nearly half of its length; bark light gray and smooth in young trees, darker, scaly, and narrowly furrowed in older trees; terminal buds reddish, glabrous, to 4 mm long with 4 overlapping (imbricate) pairs of bud scales.
Nomenclatural Notes: The former Aceraceae (Maple Family) is now included in the Sapindaceae (Soapberry Family).
Leaves: Opposite, simple, glabrous, petiolate, with petioles up to 10 cm long; leaf blade palmate, 3-5 lobed, to 15 cm long, underside paler; margins serrate. Leaves turn to red in autumn.
Flowers: Red, in sessile clusters of bisexual and male flowers on some plants, bisexual and female flowers on other plants (polygamodioecious), appearing before the leaves; calyx 5-lobed, red; petals 5, red, linear-oblong, pubescent; stamens 4-12 (often 8); ovary superior, glabrous, 2-carpelled, styles 2. Flowering April to May.
Fruits: A pair of winged samaras, to 2.5 cm long; with an acute angle between the divergent wings.
Habitat and Range: Occurs in a wide variety of soil types and moisture regimes in deciduous forests. Common throughout much of eastern North America as far south as Florida.
Similar Species: Acer saccharum (sugar maple) has leaves with entire margins between the 5 main lobes, each with acuminate apices; the middle 3 lobes are divided into 3 smaller, acuminate lobes; leaves turn yellow to orange and red in autumn.
Acer saccharinum (silver maple) has more deeply lobed with coarsely serrate margins and more strongly whitened lower surfaces; the leaves turn yellow in autumn.
Internet Images: The Acer rubrum webpage from the Trees in Canada website.
The Acer rubrum fact sheet from the Dendrology at Virginia Tech website.
- written by Derek Goertz
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