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• Asteraceae
• Asteraceae Group 2
• Symphyotrichum
• Symphyotrichum tradescantii

Symphyotrichum tradescantii — Tradescant's American-aster

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

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 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
  • 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

  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 (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

  • 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)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae