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Symphyotrichum boreale — rush American-aster

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Facts

Rush American-aster is found in high-pH fens and marshes in northern North America, including Maine, New Hampshire and Vermont. This species has distinctively long and very narrow leaves, often with revolute margins.

Habitat

Fens

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
wetlands
New England state
  • Maine
  • New Hampshire
  • Vermont
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 no teeth or lobes
  • 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
15–150 mm
Disk flower number
  • 11-20
  • 21-50
Show all characteristics
  • Flowers

    Bases of bract appendages
    NA
    Bract color
    the bracts are colored, or at least tinged with, pink, red or purple
    Bract cycle number
    there are three or more cycles of bracts
    Bract inner side hairs
    the bracts are not hairy on their inner surfaces
    Bract keels
    the bracts do not have keels
    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 separation
    the bracts appear completely unconnected to one another on all flower heads
    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 oblong (roughly rectangular but rounded at the ends)
    Bract spines
    the bracts have no spines
    Bract texture
    • the bracts appear leathery or hardened
    • the bracts appear thin, flexible and nearly translucent
    • 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
    • the tips of the bracts curve outwards and downwards from the plant
    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)
    Bracts
    the bracts in separate cycles are similar or gradually changing from the outer to inner cycles
    Disk flower color
    • blue to purple
    • green to brown
    • pink to red
    • yellow
    Disk flower lobe number
    5
    Disk flower number
    • 11-20
    • 21-50
    Disk flower proportions
    • 0-15%
    • 16-30%
    Disk flower reproductive parts
    the disk flower has both pollen- and seed-producing parts
    Disk flower shape
    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
    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
    Up to 4 mm
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
    Inflorescence stem
    the stem of the inflorescence is not hairy
    Ovary attachment
    the ovary is attached at or near the base
    Ovary beak
    there is no beak on the ovary
    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
    • there are three lines or ribs visible on the ovary
    Ovary profile
    in profile, the ovary is roughly egg-shaped, but widest above the middle
    Ovary surface
    the ovary surface has no points, bumps or wrinkles, though it may have lines, ribs or wings
    Ovary wing number
    0
    Peduncle hair type
    NA
    Peduncle hairs
    the peduncles have no hairs
    Peduncle length
    5–50 mm
    Ray flower color
    blue to purple
    Ray flower reproductive parts
    the ray flowers have carpels or stamens, but not both
    Ray flowers
    • 16-25
    • 26-50
    Ray length
    7–20 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
    Width of flower head base
    At least 8 mm
  • Fruits or seeds

    Number of pappus parts
    11 or more
    Ovary beak length
    0 mm
    Ovary length in developed fruit
    0.6–2 mm
    Seed hair tuft bases
    the pappus hairs are not attached to one another near the base
    Seed hair tuft color
    the pappus hairs are white or off-white
    Seed hair tuft details
    the pappus hairs are hooked or barbed
    Seed hair tuft length
    2.7–6.7 mm
    Seed hair tuft tips
    the pappus hairs are slender
    Seed hairs uniform
    all the pappus hairs are approximately the same length
    Seed tuft scale number
    0
    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

    Leaf blade glands
    the leaf blades have no glandular (translucent) dots or scales
    Ovary glands
    there are no visible glands on the ovary
    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 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 no 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
    Leaf blade edges
    • the edge of the leaf blade has no teeth or lobes
    • the edge of the leaf blade has teeth
    Leaf blade flatness
    the edges of the leaf are curled under
    Leaf blade hairs
    NA
    Leaf blade length
    15–150 mm
    Leaf blade shape
    • the leaf blade is linear (very narrow with more or less parallel sides)
    • the leaf blade is oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
    • the leaf blade is oblong (rectangular but with rounded ends)
    • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
    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 veins
    the leaf blade has one main vein running from the base towards the tip
    Leaf blade width
    2–9 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 no leaf stalks, but attach directly to the stem
    Leaf stalk length
    0 mm
    Leaf tip extension
    NA
    Leaf tufts in axils
    there are no clusters of smaller leaves
    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
    wetlands
    New England state
    • Maine
    • New Hampshire
    • Vermont
    Specific habitat
    fens
  • Stem, shoot, branch

    Flowering stem cross-section
    the flowering stem is circular, or with lots of small angles
    Leaves on stem
    there is at least one full leaf above the base of the flowering stem
    Stem bloom
    the stem has a powdery or waxy film on it that can be rubbed away
    Stem internode hair direction
    NA
    Stem internode hair type
    the stem has no hairs between the nodes
    Stem internode hairs
    the stem has no hairs between the nodes
    Stem wings
    the stem does not have wings on it

Wetland status

Occurs only in wetlands. (Wetland indicator code: OBL)

In New England

Distribution

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

Conservation status

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

Maine
fairly widespread (S-rank: S4)
New Hampshire
unrankable (S-rank: SU), Ind (code: Ind)
Vermont
historical (S-rank: SH)

From Flora Novae Angliae dichotomous key

2.  Symphyotrichum boreale (Torr. & Gray) A. & D. Löve N

rush American-aster. Aster borealis (Torr. & Gray) Prov.; A. junciformis Rydb. • ME, NH, VT. Circumneutral fens. The report of this species in MA (e.g., Sorrie and Somers 1999) is based on a collection of Symphyotrichum novi-belgii var. elodesGoodale et al. 69563 ( MASS!).

Native to North America?

Yes

Sometimes confused with

Symphyotrichum anticostense:
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 (vs. S. boreale, with 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).

Synonyms

  • Aster borealis (Torr. & Gray) Prov.
  • Aster junciformis Rydb.

Family

Asteraceae