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- Symphyotrichum tradescantii
Symphyotrichum tradescantii — Tradescant's American-aster
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Facts
Tradescant's American-aster is restricted to northeastern North America. In New England it occurs on rocky and ledgy, seasonally flooded river shores in Maine, Vermont, and New Hampshire, and rarely in Massachusetts.
Habitat
Ridges or ledges, shores of rivers or lakes
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
-
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
-
- alternate: there is one leaf per node along the stem
- the leaves are growing only at the base of the plant (basal)
- 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
- 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
- 30–100 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 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 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 oblong (roughly rectangular but rounded at the ends)
- Bract spines
- NA
- 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 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)
- 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
- 31-45%
- 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
- 4–6 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 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
- NA
- Peduncle hairs
- the peduncles have no hairs
- Peduncle length
- 2–25 mm
- Ray flower color
- white
- Ray flower reproductive parts
- the ray flowers have carpels or stamens, but not both
- Ray flowers
-
- 11-15
- 16-25
- 26-50
- Ray length
- 3–8 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
- 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
- 3.5–4 mm
- 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
- 3–3.6 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
- 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
- the leaves are growing only at the base of the plant (basal)
- Leaf blade base
-
- the leaf has a distinct petiole
- the leaf has no petiole
- 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 hairs
- NA
- Leaf blade length
- 30–100 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 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 spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)
- 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)
- the tip of the leaf blade is obtuse (bluntly pointed)
- Leaf blade width
- 3–10 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
- the leaves have no leaf stalks, but attach directly to the stem
- Leaf stalk length
- At least 0 mm
- Leaf tip extension
- NA
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets
-
Place
- Habitat
-
- terrestrial
- wetlands
- New England state
-
- Maine
- Massachusetts
- New Hampshire
- Vermont
- 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
- NA
- Stem internode hair length
- 0 mm
- Stem internode hair type
- the stem has no hairs between the nodes
- Stem internode hairs
- the stem has no hairs between the nodes
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- present
- 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.
- Massachusetts
- rare (S-rank: S2), threatened (code: T)
- Vermont
- rare (uncertain) (S-rank: S2?)
From Flora Novae Angliae dichotomous key
25. Symphyotrichum tradescantii (L.) Nesom N
Tradescant’s American-aster. Aster saxatilis (Fern.) Blanch., nom. illeg.; A. tradescantii L.; A. tradescantii L. var. saxatilis (Fern.) House; A. vimineus Lam. var. saxatilis Fern. • MA, ME, NH, VT; also reported from RI by George (1992), but specimens are unknown. Rocky and ledgy shorelines, most frequently rivers.