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- Asteraceae
- Asteraceae Group 4
- Oclemena
- Oclemena nemoralis
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
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
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
-
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.