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• Acer palmatum

Acer palmatum — Japanese maple

Facts

Japanese maple is a beloved member of many people's gardens, with its versatile forms, vase-like branching shape, and delicate, toothed, palmate leaves that turn deep red in the fall. It has become naturalized occasionally along roadsides and forest borders in warmer regions of New England.

Habitat

Anthropogenic (man-made or disturbed habitats), forest edges, forests, meadows and fields

Characteristics

• 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

  Collateral buds

  there are no collateral buds on the sides of the branches

  Superposed buds

  there are no superposed buds on the branch

  Winter bud scales

  the winter bud is perulate (partially or completely covered with one or more scales)

• 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

  • pink
  • white
  • yellow or green

  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 is a corymb (with long lower branches and shorter upper branches, giving it a more or less flat-topped look)
  • the inflorescence is a panicle (branched with the individual flowers on stalks)

  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 cilia (Ilex)

  NA

  Stamen number

  8

  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 shrub (a woody plant with several stems growing from the base)
  • the plant is a tree

• Leaves

  Hairs on upper side of leaf blade

  • the upper side of the leaf is fuzzy or hairy
  • 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)
  • the base of the leaf blade is truncate (ends abruptly in a more or less straight line as though cut off)

  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

  the hairs on the leaf blade are different from the choices given

  Leaf blade length

  30–60 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)

  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 width

  40–80 mm

  Leaf duration

  the leaves drop off in winter (or they wither but persist on the plant)

  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 nectaries

  there are no nectaries on the leaf stalk

  Leaf teeth

  • the leaf blade margin has teeth, which themselves have smaller teeth on them
  • 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 (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 (lobed or unlobed but not separated into leaflets

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Massachusetts

  Specific habitat

  • edges of forests
  • forests
  • man-made or disturbed habitats
  • meadows or fields

• 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 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

  Pith shape

  the outline of the pith in a twig is roughly round

  Twig papillae (Vaccinium species only)

  NA

  Twig winter color

  • green
  • 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

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae