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- Acer
- Acer rubrum
Acer rubrum — red maple
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Facts
Red maple takes its common name from its reddish buds that swell in spring, its red leaf petioles in summer, and its brilliant red foliage in fall. Although it grows largest in and near swamps, it abounds in New England forests and is becoming more common as sugar maple begins to succumb to climatic change. It grows rapidly and stump-sprouts readily. Although the wood can be used for veneer and a variety of small products such as boxes and clothespins, it is weaker and harder to work than sugar maple. Red maple also yields a sugary syrup, but in smaller quantities than sugar maple. As an early-successional forest tree, however, it provides browse for moose and many other mammals.
Habitat
Forest edges, forests, meadows and fields, shores of rivers or lakes, swamps, wetland margins (edges of wetlands), woodlands
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Growth form
- the plant is a tree
- Leaf type
- the leaf blade is simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaves per node
- there are two leaves per node along the stem
- Leaf blade edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- armature on plant
- the plant does not have spines, prickles, or thorns
- Leaf blade length
- 60–100 mm
- Leaf blade width
- 60–150 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Bark texture
-
- the bark of an adult plant is ridged or plated
- the bark of an adult plant is thin and smooth
- Twig winter color
-
- gray
- red
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
-
Buds or leaf scars
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
- Bud scar shape (Fraxinus)
- NA
- Bundle scar number
- 3
- Collateral buds
-
- the branches have collateral buds on them
- there are no collateral buds on the sides of the branches
- Leaf scar arrangement
- there are two leaf scars per node on the stem or twig
- Superposed buds
- there are no superposed buds on the branch
- Winter bud scale hairs
- the winter bud scales have no hairs on them
- Winter bud scales
- the winter bud is perulate (partially or completely covered with one or more scales)
- Winter bud shape
-
- the winter buds are lanceoloid (lance-shaped, widest below the middle and tapering to the ends)
- the winter buds are ovoid (egg-shaped)
- Winter bud stalks
-
- the winter buds have no stalks
- the winter buds have short stalks
-
Flowers
- Carpels fused
- the carpels are fused to one another
- Enlarged sterile flowers
- there are no enlarged sterile flowers on the plant
- Flower petal color
- red
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Hairs on ovary (Amelanchier)
- NA
- Hypanthium present
- the flower does not have a hypanthium
- Inflorescence type
-
- the inflorescence differs from the choices given
- the inflorescence is a fascicle (compact cluster of flowers)
- the inflorescence is an umbel (with an axis so short it appears the flowers all originate from the same point)
- Number of pistils
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal fusion
- the perianth parts are separate
- Sepal appearance
- the sepals resemble petals in color and texture
- Sepal cilia (Ilex)
- NA
- Sepal tip glands
- there are no glands at the tips of the sepal lobes
- Sepals fused only to sepals
- the sepals are separate from one another
- Stamen number
-
- 10
- 4
- 5
- 6
- 7
- 8
- 9
- Stamens fused
- the stamens are not fused to one another
-
Fruits or seeds
- Berry color
- NA
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
-
- the fruit is a schizocarp (when dry it splits into sections, each holding one or more seeds)
- the fruit is an achene (dry, usually 1-seeded, does not separate or split open at maturity)
- Nut with spines (Fagaceae)
- NA
- Wings on fruit
- the fruit has one or more wings on it
-
Glands or sap
- Sap color
- the sap is clear and watery
- Stalked glands on fruit (Rosa)
- NA
-
Growth form
- Growth form
- the plant is a tree
-
Leaves
- Hairs on underside of leaf blade
-
- the underside of the leaf has hairs on it
- the underside of the leaf has no hairs
- Hairs on upper side of leaf blade
- the upper side of the leaf is not hairy, or has very few hairs
- Leaf blade base shape
- The base of the leaf blade is cordate (heart-shaped, with rounded lobes)
- Leaf blade base symmetry
- the leaf blade base is symmetrical
- Leaf blade bloom
- there is a noticeable powdery or waxy bloom on the underside of the leaf
- Leaf blade edges
- the edge of the leaf blade has lobes, or it has both teeth and lobes
- Leaf blade edges (Acer)
- the leaves have teeth throughout the leaf blade, including between the lobes
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
-
- NA
- the hairs on the leaf blade are different from the choices given
- Leaf blade length
- 60–100 mm
- Leaf blade scales
- there are no scales on the leaf blades
- Leaf blade shape
-
- the leaf blade is orbicular (roughly circular, as wide as long)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is triangular, with the stalk or attachment point on one of the sides
- Leaf blade texture
- the leaf blade is herbaceous (has a leafy texture)
- Leaf blade translucent dots
- there are no translucent dots on the leaf blade
- Leaf blade vein pattern
- the main veins of the leaf blade are palmate (radiate out from the base, like a hand)
- Leaf blade veins
- the leaf blade has three or more main veins running from the base (or near the base) towards the tip
- Leaf blade width
- 60–150 mm
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf form
- the plant is broad-leaved (with broadly flattened leaf blades)
- Leaf lobe tips (Quercus)
- NA
- Leaf midrib glands
- the midrib of the leaf blade lacks glands on the upper surface
- Leaf stalk
- the leaves have leaf stalks
- Leaf stalk attachment to leaf
- the petiole attaches at the basal margin of the leaf blade
- Leaf stalk nectaries
- there are no nectaries on the leaf stalk
- Leaf stalk shape
- the leaf stalk is not flattened
- Leaf teeth
-
- the leaf blade margin is crenate (with rounded teeth) or crenulate (with tiny, rounded teeth)
- the leaf blade margin is serrate (with forward-pointing) or dentate (with outward-pointing) with medium-sized to coarse teeth
- Leaf teeth hairs (Carya)
- NA
- Leaf type
- the leaf blade is simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaves per node
- there are two leaves per node along the stem
- Specific leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
- Stipules
- there are no stipules on the plant, or they fall off as the leaf expands
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- edges of forests
- edges of wetlands
- forests
- meadows or fields
- shores of rivers or lakes
- swamps
- woodlands
-
Scent
- Plant odor
- the plant does not have much of an odor, or it has an unpleasant or repellant odor
-
Stem, shoot, branch
- Aerial roots
- the plant has no aerial roots
- Bark texture
-
- the bark of an adult plant is ridged or plated
- the bark of an adult plant is thin and smooth
- Branch brittleness (willows only)
- NA
- Branch cross-section
- the branch is circular in cross-section, or it has five or more sides, so that there are no sharp angles
- First-year cane (Rubus)
- NA
- Lenticels on twigs
- there are clearly lenticels on the twigs
- Pith shape
- the outline of the pith in a twig is roughly round
- Pith type
- the pith inside the twig is solid, completely filled with spongy tissue
- Short shoots
- there are no peg- or knob-like shoots present
- Twig bloom
- there is no bloom on the twig
- Twig hairs
- the twigs have few or no hairs on them
- Twig papillae (Vaccinium species only)
- NA
- Twig scales
- there are no scales on the twig surface
- Twig winter color
-
- gray
- red
- Wings on branch
- the branch does not have wings on it
- armature on plant
- the plant does not have spines, prickles, or thorns
Wetland status
Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- unranked (S-rank: SNR)
- Massachusetts
- widespread (S-rank: S5)
From Flora Novae Angliae dichotomous key
9. Acer rubrum L. N
red maple. Acer carolinianum Walt.; A. rubrum L. var. tridens Wood; A. stenocarpum Britt.; Rufacer rubrum (L.) Small; R. carolinianum (Walt.) Small • CT, MA, ME, NH, RI, VT; nearly throughout. Deciduous and mixed evergreen-deciduous forests, swamps, riparian forests, shorelines, successional fields.
9×10. Acer rubrum × Acer saccharinum → Acer ×freemanii Murray is a rare maple hybrid known from MA, ME, NH, VT. The leaf blades are similar to A. saccharinum but have V-shaped sinuses, a shorter central lobe, and teeth distributed over the apical 50–75% of the lobes.
Native to North America?
Yes
Sometimes confused with
- Acer ginnala:
- leaf blades green on the abaxial surface, the terminal lobe substantially longer than the adjacent lateral lobes (vs. A. rubrum, with leaf blades thinly glaucous on abaxial surface, the terminal lobe as long as or somewhat longer than the adjacent lateral lobes).
- Acer saccharinum:
- leaf blades with teeth mainly concentrated on the upper half of the lobes and fruit hairy over the seed (vs. A. rubrum, with leaf blades with teeth distributed over the entire margin and fruit without hairs over the seed).
Synonyms
- Acer carolinianum Walt.
- Acer rubrum var. tridens Wood
- Acer stenocarpum Britt.
- Rufacer carolinianum (Walt.) Small
- Rufacer rubrum (L.) Small