Your help is appreciated. We depend on donations to help keep this site free and up to date for you. Can you please help us?

Donate

Native Plant Trust: Go Botany Discover thousands of New England plants

Populus heterophylla — swamp poplar

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

Facts

Swamp poplar is native to eastern North America, parts of the midwest, and along the Mississippi River basin. It is at the northern limit of its range in New England, with a few populations each in Connecticut, Massachusetts, and Rhode Island. It is an inhabitant of wetlands and seasonally flooded depressions.

Habitat

Shores of rivers or lakes, swamps

New England distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America distribution

Adapted from BONAP data

enlarge

Characteristics

Habitat
  • terrestrial
  • wetlands
New England state
  • Connecticut
  • Massachusetts
  • Rhode Island
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 is one leaf per node along the stem
Leaf blade edges
the edge of the leaf blade has teeth
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
35–240 mm
Leaf blade width
35–190 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
Twig winter color
  • brown
  • 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
Show all 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
  • Flowers

    Carpels fused
    the carpels are fused to one another
    Enlarged sterile flowers
    there are no enlarged sterile flowers on the plant
    Flower appearance
    the flowers appear before the leaves
    Flower petal color
    NA
    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 an ament (catkin; slender, usually pendulous inflorescence with crowded unisexual flowers)
    Number of pistils
    1
    Ovary position
    the ovary is above the point of petal and/or sepal attachment
    Petal and sepal arrangement
    the flower lacks sepals and petals
    Petal appearance
    NA
    Petal fusion
    NA
    Sepal appearance
    NA
    Sepal cilia (Ilex)
    NA
    Sepal tip glands
    NA
    Sepals fused only to sepals
    NA
    Stamen number
    • 12
    • 13 or more
    Stamen position relative to petals
    NA
    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 capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
    Nut with spines (Fagaceae)
    NA
    Wings on fruit
    there are no wings on the fruit
  • 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 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 edges
    the edge of the leaf blade has teeth
    Leaf blade edges (Acer)
    NA
    Leaf blade flatness
    the leaf is flat (planar) at the edges
    Leaf blade hairs
    • at least some of the hairs on the leaf blade have glands at their tips
    • the hairs on the leaf blade are different from the choices given
    Leaf blade length
    35–240 mm
    Leaf blade scales
    there are no scales on the leaf blades
    Leaf blade shape
    the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
    Leaf blade texture
    • the leaf blade is coriaceous (has a firm, leathery 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
    35–190 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 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 is one leaf per node along the stem
    Specific leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Massachusetts
    • Rhode Island
    Specific habitat
    • shores of rivers or lakes
    • swamps
  • 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
    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
    • brown
    • 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 only in wetlands. (Wetland indicator code: OBL)

In New England

Distribution

Connecticut
present
Maine
absent
Massachusetts
present
New Hampshire
absent
Rhode Island
present
Vermont
absent

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Connecticut
rare (S-rank: S2), threatened (code: T)
Massachusetts
extremely rare (S-rank: S1), endangered (code: E)
Rhode Island
extremely rare (S-rank: S1), state endangered (code: SE)

From Flora Novae Angliae dichotomous key

5.  Populus heterophylla L. NC

swamp poplar. CT, MA, RI. Swamps, pond shores.

Native to North America?

Yes

Sometimes confused with

Populus balsamifera:
leaf blades acute to short-acuminate at the apex, broad-cuneate to subcordate at the base, often with streaks of orange resin on the abaxial surface, glabrous, and terminal winter bud very viscid (vs. P. heterophylla, with leaf blades obtuse to rounded at the apex, cordate at the base, sometimes narrowed to a short, broad base prior to junction with petiole, without orange resin on the abaxial surface, permanently pubescent on the abaxial veins, and terminal winter bud not or scarcely viscid).

Family

Salicaceae

Genus

Populus