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• Asteraceae
• Asteraceae Group 2
• Liatris
• Liatris pycnostachya

Liatris pycnostachya — thick-spiked blazing star

Facts

Thick-spiked blazing star is native to the central and midwestern states, and introduced in New England. Because it is commonly grown as a garden plant, occurrences in Massachusetts and Maine probably represent horticultural escapes.

Habitat

Anthropogenic (man-made or disturbed habitats), meadows and fields

Characteristics

• Flowers

  Bract cycle number

  there are three or more cycles of bracts

  Bract margins

  • there are few or no fine hairs along the 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
  • the bracts are not hairy 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 shape

  • the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
  • the main bracts are oblong (roughly rectangular but rounded at the ends)

  Bract spines

  the bracts have no spines

  Bract tip orientation

  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

  there are at least two distinct forms of bracts in different cycles

  Disk flower color

  • blue to purple
  • pink to red

  Disk flower number

  • 1-5
  • 11-20
  • 6-10

  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 outer flowers

  at the outer edge of the flower head, the flowers have no enlarged lobe or strap, and are of similar size as those in the center of the disk

  Flower head platform

  the base has no bristles or papery scales

  Flower head profile

  the disk is flat or nearly flat across the top

  Flower head shape

  the sides of the flower head are roughly parallel, like a cylinder

  Flower head width

  Up to 2.9 mm

  Flower type in flower heads

  the flower head has disk flowers only, and lacks the strap-shaped flowers

  Height of flower head base

  7–11 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

  hairs are present on the stem of the inflorescence

  Ovary cross-section

  the ovary has five or more corners in cross-section

  Ovary hairs

  the ovary has hairs on it

  Ovary lines or ribs

  • there are seven to nine ribs visible on the ovary
  • there are ten or more ribs visible on the ovary

  Ovary profile

  in profile, the ovary is another shape

  Peduncle hairs

  the peduncles are hairy

  Peduncle length

  0–2 mm

  Ray flower color

  NA

  Ray flower reproductive parts

  NA

  Ray flowers

  NA

  Reproductive system

  all the flowers on the plant contain both carpels and stamens

  Smaller bracts at base of bracts

  there is a cycle of much smaller bracts outside the cycle of larger and longer bracts

  Style branches

  the style branch is wider at the tip and has a flattened end, or the style branches are wider at the tips and have flattened ends

  Width of flower head base

  3.5–5 mm

• Fruits or seeds

  Number of pappus parts

  11 or more

  Ovary length in developed fruit

  3.8–5 mm

  Seed hair tuft details

  the pappus hairs are hooked or barbed

  Seed hair tuft tips

  the pappus hairs are slender

  Seed hairs uniform

  all the pappus hairs are approximately the same length

  Seed tuft type

  the pappus is made of very fine hairs or bristles

  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 glandular (translucent) dots or scales

  Ovary glands

  there are glands on the ovary surface

• 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)
  • the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms

• Leaves

  Hairs on underside of leaf blade

  • the underside of the leaf is fuzzy or hairy
  • 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
  • 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

  Leaf blade length

  110–220 mm

  Leaf blade shape

  • 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)

  Leaf blade veins

  the leaf blade has three main veins running from the base towards the tip

  Leaf blade width

  4–12 mm

  Leaf disposition

  the lower leaves are larger, toothier, and/or on longer stalks than the upper leaves

  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 type

  leaves are simple (lobed or unlobed but not separated into leaflets)

  Specific leaf type

  the leaves are simple (lobed or unlobed but not separated into leaflets

• Place

  Habitat

  terrestrial

  New England state

  • Maine
  • Massachusetts

  Specific habitat

  • man-made or disturbed habitats
  • meadows or fields

• 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
  • 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

Wetland status

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae