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

Symphyotrichum anticostense — Anticosti American-aster

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Facts

You won't encounter Anticosti American-aster unless you are in a few sites in Canada, or on Maine's Aroostook River near the Canadian border. A globally imperiled species, it derives from a cross between New York American-aster (Symphyotrichum novi-belgii) and rush American-aster (S. boreale). Its greatest threats are river damming and invasive plants.

Habitat

Ridges or ledges, shores of rivers or lakes

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
terrestrial
New England state
Maine
Leaf type
leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
Leaf arrangement
  • alternate: there is one leaf per node along the stem
  • basal: the leaves are growing only at the base of the plant
Leaf blade edges
the edge of the leaf blade has teeth
Flower type in flower heads
the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery
Ray flower color
blue to purple
Tuft or plume on fruit
at least a part of the plume is made up of fine bristles
Spines on plant
the plant has no spines
Leaf blade length
55–160 mm
Disk flower number
  • 21-50
  • more than 50
Show all characteristics
  • Flowers

    Bases of bract appendages
    NA
    Bract color
    the bracts are not colored or tinged with pink, red or purple
    Bract cycle number
    • there are three or more cycles of bracts
    • there are two main cycles of bracts
    Bract inner side hairs
    the bracts are not hairy on their inner surfaces
    Bract margins
    there are fine hairs along the bract margins
    Bract outer side hair type
    the bracts are not hairy on their outer surface
    Bract outer side hairs
    the bracts are not hairy on their outer surfaces
    Bract shape
    • the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
    • the main bracts are linear (long and very narrow)
    • the main bracts are oblanceolate (widest near the tip, but otherwise narrow and tapering)
    • the main bracts are oblong (roughly rectangular but rounded at the ends)
    • the main bracts are of a different shape than the given options
    Bract spines
    the bracts have no spines
    Bract texture
    • the bracts appear leathery or hardened
    • the bracts have a similar texture to a leaf
    Bract tip color
    the tips are a different color from the center of the bract
    Bract tip extension appearance
    NA
    Bract tip extension edge
    there are no projections from the bract tips
    Bract tip orientation
    the bracts are pressed against the plant, or spreading out at the tips
    Bract tip shape
    • the tips of the bracts acute (have a sharp point)
    • the tips of the bracts are acuminate (tapered to a narrow point)
    Bract width
    1.5–2
    Bracts
    the bracts in separate cycles are similar or gradually changing from the outer to inner cycles
    Disk flower color
    • blue to purple
    • yellow
    Disk flower lobe number
    5
    Disk flower number
    • 21-50
    • more than 50
    Disk flower reproductive parts
    the disk flower has both pollen- and seed-producing parts
    Disk flower shape
    • the disk flower is abruptly widened at some point below the lobes
    • the disk flower is tube-shaped (cylindrical), or gradually widening like a funnel
    Flower head number
    each flowering stem has four or more flower heads on it
    Flower head outer flowers
    at the outer edge of the flower head, each flower has a single enlarged lobe or strap
    Flower head platform
    the base has no bristles or papery scales
    Flower head platform surface
    NA
    Flower head position
    • each of the flower heads is separate on its own peduncle (stalk), not clustered in groups
    • some or all the flower heads are grouped in clusters of two or more
    Flower head profile
    • the disk is flat or nearly flat across the top
    • the disk is rounded across the top
    Flower head shape
    the sides of the flower head are roughly parallel, like a cylinder
    Flower type in flower heads
    the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery
    Height of flower head base
    6–10 mm
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
    Ovary cross-section
    the ovary is compressed (flattened)
    Ovary hair type
    the ovary has hairs on it, but the hairs have no glands
    Ovary hairs
    the ovary has hairs on it
    Ovary lines or ribs
    there are four to six lines or ribs visible on the ovary
    Ovary profile
    in profile, the ovary is roughly egg-shaped, but widest above the middle
    Peduncle hair type
    the hairs on the peduncles are simple (not branched), don’t have glands, and are not woolly
    Peduncle hairs
    the peduncles are hairy
    Peduncle length
    8–57 mm
    Ray flower color
    blue to purple
    Ray flower reproductive parts
    the ray flowers have carpels or stamens, but not both
    Ray flowers
    26-50
    Ray length
    9.5–20 mm
    Reproductive system
    some of the flowers on the plant have only carpels or stamens, while others have both carpels and stamens
    Scale tip
    NA
    Smaller bracts at base of bracts
    there is a cycle of much smaller bracts outside the cycle of larger and longer bracts
    Style branch number
    the style has two branches
    Style branches
    the style branch is narrow at the tip, or the style branches are narrow at the tips
  • Fruits or seeds

    Number of pappus parts
    11 or more
    Ovary length in developed fruit
    1.5–2.8 mm
    Seed hair tuft color
    the pappus hairs are another color
    Seed hair tuft details
    the pappus hairs are hooked or barbed
    Seed hair tuft length
    7–8 mm
    Seed hair tuft tips
    the pappus hairs are slender
    Seed hairs uniform
    all the pappus hairs are approximately the same length
    Seed tuft type
    the pappus is made of very fine hairs or bristles
    Top of disk flower ovary
    NA
    Tuft or plume on fruit
    at least a part of the plume is made up of fine bristles
  • Glands or sap

    Sap
    the sap is clear and watery
  • Growth form

    Growth form
    the plant has one or more free-standing stems
    Plant lifespan
    the plant is perennial, it shows evidence of previous year's leaves, stems or stem bases
    Spines on plant
    the plant has no spines
    Underground organs
    the plant has a rhizome (a horizontal underground stem with roots growing from it)
  • Leaves

    Final leaf segment length (compound lvs only)
    0 mm
    Final leaf segment width (compound lvs only)
    0 mm
    Hairs on underside of leaf blade
    • the underside of the leaf is fuzzy or hairy
    • the underside of the leaf is not hairy, or has very few hairs
    Hairs on upper side of leaf blade
    the upper side of the leaf is not hairy, or has very few hairs
    Leaf arrangement
    • alternate: there is one leaf per node along the stem
    • basal: the leaves are growing only at the base of the plant
    Leaf blade base
    • the leaf has a distinct petiole
    • the leaf has no petiole and at the base it clasps the stem, or goes all the way around the stem so the stem appears to pierce the leaf
    Leaf blade base shape
    • the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow
    • the base of the leaf blade is rounded
    Leaf blade edges
    the edge of the leaf blade has teeth
    Leaf blade flatness
    the edges of the leaf are curled under
    Leaf blade hairs
    • NA
    • the leaf blade has simple hairs with no glands, and not tangled or wooly
    Leaf blade length
    55–160 mm
    Leaf blade shape
    • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
    • the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
    Leaf blade surface colors
    there is no noticeable color variation on the upper surface of the leaf
    Leaf blade tip
    • the tip of the leaf blade is acuminate (tapers to a long, thin point)
    • the tip of the leaf blade is acute (sharply pointed)
    Leaf blade width
    5–25 mm
    Leaf disposition
    the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
    Leaf spines
    there are no spines on the leaf edges
    Leaf stalk
    the leaves have leaf stalks
    Leaf tip extension
    NA
    Leaf type
    leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Leaflet number
    0
    Specific leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
  • Place

    Habitat
    terrestrial
    New England state
    Maine
    Specific habitat
    • ridges or ledges
    • shores of rivers or lakes
  • Stem, shoot, branch

    Leaves on stem
    there is at least one full leaf above the base of the flowering stem
    Stem internode hair direction
    the hairs point mostly upwards to outwards
    Stem internode hair type
    • the hairs on the stem are plain, without glands or branches, and not tangled
    • the stem has no hairs between the nodes
    Stem internode hairs
    • the stem has hairs between the nodes
    • the stem has no hairs between the nodes

Wetland status

Not classified

In New England

Distribution

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

Conservation status

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

Maine
extremely rare (S-rank: S1), endangered (code: E)

From Flora Novae Angliae dichotomous key

1.  Symphyotrichum anticostense (Fern.) Nesom NC

Anticosti American-aster. Aster anticostensis Fern. • ME; northern portion of state. Ice-scoured river shores and adjacent, disintegrating ledges.

Native to North America?

Yes

Sometimes confused with

Symphyotrichum boreale:
leaf blades linear to oblong-linear, often with revolute margins, mostly 2–5 mm wide, base of stem thinner than 2.5 mm, and plants mostly of high-pH fens (vs. S. anticostense, with leaf blades usually narrow-lanceolate , with plane margins, 5–25 mm wide, base of stem thicker than 2.5 mm, and plants mostly of river shores).
Symphyotrichum novi-belgii:
leaf blades narrow-lanceolate to oblanceolate, narrowing to the base, flat, herbaceous to fleshy, and most peduncles shorter than 3 cm (vs. leaf blades tending to be narrow-lanceolate, scarcely narrowing to the base, folded along the midrib, coriaceous, and many peduncles longer than 3 cm).

Synonyms

  • Aster anticostensis Fern.

Family

Asteraceae