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- Symphyotrichum
- Symphyotrichum prenanthoides
Symphyotrichum prenanthoides — crooked-stemmed American-aster
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Facts
Crooked-stemmed American-aster is rare in New England, where it has been found in Connecticut, Vermont, and most abundantly in Massachusetts, where it is listed as threatened. It occurs in open areas and along edges of moist to wet, often riparian, forests, and on roadsides. The name is due to the slight zig-zag form of the main stem as it changes direction from node to node.
Habitat
Floodplain (river or stream floodplains), forest edges, meadows and fields, 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
-
- Connecticut
- Massachusetts
- 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 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
- 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
- 15–200 mm
- Disk flower number
-
- 21-50
- more than 50
-
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
- Bract inner side hairs
-
- the bracts are hairy on their inner surfaces
- 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 hairy, with simple hairs on their outer surface
- Bract outer side hairs
-
- the bracts are hairy on their outer surfaces
- 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 oblanceolate (widest near the tip, but otherwise narrow and tapering)
- 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
- the tips are the same color as 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
-
- 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 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
- 5–6 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
-
- the inflorescence is flat-topped in profile
- the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
- 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
- Ovary lines or ribs
- there are four to six lines or ribs visible on the ovary
- Ovary profile
-
- in profile, the ovary is lance-shaped, but widest above the middle
- 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
- 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
- 8–40 mm
- Ray flower color
-
- blue to purple
- white
- Ray flower reproductive parts
- the ray flowers have carpels or stamens, but not both
- Ray flowers
-
- 16-25
- 26-50
- Ray length
- 7.5–15 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
- 8–15 mm
-
Fruits or seeds
- Number of pappus parts
- 11 or more
- Ovary beak length
- 0 mm
- Ovary length in developed fruit
- 2–3.5 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
- 3.5–4.5 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 fuzzy or hairy
- 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
- 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 teeth
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- the leaf blade has simple hairs with no glands, and not tangled or wooly
- Leaf blade length
- 15–200 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 oblanceolate (lance-shaped, but with the widest point above the middle of the leaf blade)
- the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- 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 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
- 10–20 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 (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
- wetlands
- New England state
-
- Connecticut
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- edges of forests
- meadows or fields
- river or stream floodplains
- shores of rivers or lakes
-
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 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
- Stem wings
- the stem does not have wings on it
Wetland status
Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- 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.
- Connecticut
- historical (S-rank: SH), special concern, extirpated (code: SC*)
- Massachusetts
- uncommon (S-rank: S3), special concern (code: SC)
From Flora Novae Angliae dichotomous key
20. Symphyotrichum prenanthoides (Muhl. ex Willd.) Nesom N│EC
crooked-stemmed American-aster. Aster prenanthoides Muhl. ex Willd. • CT, MA, NH, VT; introduced to an open ski slope in NH and native elsewhere. In open areas and along edges of mesic to wet-mesic forests, often riparian types.
Native to North America?
Yes
Synonyms
- Aster prenanthoides Muhl. ex Willd.