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Oclemena nemoralis — bog aster, bog nodding-aster

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Facts

Bog nodding-aster is confined to northeastern North America, where it is found mainly in wetlands, especially acidic bogs. The Chippewa made a decoction of the rhizome, for use as ear drops or in a compress for sore ear. Bog nodding-aster frequently hybridizes with the forest species sharp-toothed nodding-aster (Oclemena acuminatus) where their habitats overlap.

Habitat

Anthropogenic (man-made or disturbed habitats), bogs, fens, meadows and fields, shores of rivers or lakes, wetland margins (edges of wetlands)

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
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • 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
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
  • pink to red
  • white
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
10–60 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
    • the bracts are not colored or tinged with pink, red or purple
    Bract cycle number
    there are three or more cycles of bracts
    Bract keels
    the bracts do not have keels
    Bract margins
    there are few or no fine hairs along the bract margins
    Bract outer side hair type
    • the bracts are hairy on their outer surfaces, with hairs having glands (a swelling at the tip of the hair)
    • the bracts are hairy, with simple hairs on their outer surface
    Bract outer side hairs
    the bracts are 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)
    Bract spines
    the bracts have no spines
    Bract texture
    • 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
    Bract tip shape
    the tips of the bracts acute (have a sharp point)
    Bracts
    the bracts in separate cycles are similar or gradually changing from the outer to inner cycles
    Disk flower color
    yellow
    Disk flower lobe number
    5
    Disk flower number
    • 11-20
    • 21-50
    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
    Flower head number
    • each flowering stem has four or more flower heads on it
    • each flowering stem has only one to three 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
    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
    Flowering stem width
    1–2 mm
    Height of flower head base
    5–7.5 mm
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    the inflorescence is flat-topped in profile
    Inflorescence stem
    hairs are present on the stem of the inflorescence
    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
    • the ovary has no hairs on it
    Ovary lines or ribs
    • there are four to six lines or ribs visible on the ovary
    • there are seven to nine ribs visible on the ovary
    Ovary profile
    • in profile, the ovary is another shape
    • in profile, the ovary is lance-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
    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
    30–70 mm
    Peduncle orientation
    the flower heads are arching outwards or downwards
    Ray flower color
    • blue to purple
    • pink to red
    • white
    Ray flower reproductive parts
    the ray flowers have carpels or stamens, but not both
    Ray flowers
    • 11-15
    • 16-25
    Ray length
    11–18 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

    Ovary length in developed fruit
    1.9–3 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 pale red to red-brown or purple
    • the pappus hairs are white or off-white
    Seed hair tuft details
    the pappus hairs are hooked or barbed
    Seed hair tuft tips
    the pappus hairs are slender
    Seed hairs uniform
    there are two distinct lengths of pappus hairs
    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

    Bract resin
    • the bracts have no resin or resin glands
    • the bracts have resin or resin glands
    Leaf blade glands
    the leaf blades have no glandular (translucent) dots or scales
    Ovary glands
    there are glands on the ovary surface
    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
    Hairs on upper side of leaf blade
    the upper side of the leaf is fuzzy or hairy
    Leaf arrangement
    alternate: there is one leaf per node along the stem
    Leaf blade base
    the leaf has no petiole
    Leaf blade base shape
    the base of the leaf blade is rounded
    Leaf blade bloom
    the underside of the leaf has no noticeable bloom
    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
    the leaf blade has hairs with glands at their tips
    Leaf blade length
    10–60 mm
    Leaf blade shape
    • the leaf blade is elliptic (widest near the middle and tapering at both ends)
    • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
    • the leaf blade is linear (very narrow with more or less parallel sides)
    • the leaf blade is oblong (rectangular but with rounded 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 acute (sharply pointed)
    • the tip of the leaf blade is obtuse (bluntly pointed)
    Leaf blade veins
    the leaf blade has one main vein running from the base towards the tip
    Leaf blade width
    2–12 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 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
    Teeth per side of leaf blade
    0
  • Place

    Habitat
    • terrestrial
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • bogs
    • edges of wetlands
    • fens
    • man-made or disturbed habitats
    • meadows or fields
    • shores of rivers or lakes
  • Scent

    Plant odor
    the plant does not have much of an odor
  • 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
    there is no powdery or waxy film on the stem
    Stem internode hair direction
    the hairs are pressed flat against the plant, pointing either towards the plant's tip or towards it's base
    Stem internode hair type
    at least some of the hairs on the stem have glands
    Stem internode hairs
    the stem has 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
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.

Connecticut
extremely rare (S-rank: S1), endangered (code: E)
Maine
unranked (S-rank: SNR)
Massachusetts
fairly widespread (S-rank: S4)
Vermont
rare (S-rank: S2)

From Flora Novae Angliae dichotomous key

2.  Oclemena nemoralis (Ait.) Greene N

bog nodding-aster. Aster nemoralis Ait. • CT, MA, ME, NH, RI, VT; mainly in eastern New England. Bogs, fens, mossy lake shores, ditches, and meadows.

1×2. Oclemena acuminata × Oclemena nemoralis Oclemena ×‌blakei (Porter) Nesom is a frequent hybrid where the habitat of the two parental species overlap. It is known from CT, MA, ME, NH, RI, VT. It is recognized by its somewhat firm leaf blades 5–24 mm wide, with small teeth, and numbering 20–45 below the capitulescence.

Native to North America?

Yes

Sometimes confused with

Oclemena acuminata:
rays white or tinged with pink, leaves herbaceous, prominently toothed, with flat margins, the blades 15–60 mm wide, those of the stem below the capitulescence mostly numbering 10–22 (vs. O. nemoralis, with rays pink to purple, leaves firm, entire or nearly so, often with revolute margins, the blades 2–12 mm wide, those of the stem below the capitulescence numbering 40–75).

Synonyms

  • Aster nemoralis Ait.

Family

Asteraceae

Genus

Oclemena