Cirsium vulgare — common thistle

Characteristics

• 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 keels

  the bracts do not have keels

  Bract outer side hair type

  • the bracts are hairy on their outer surfaces, with curled, tangled, matted, or woolly hairs
  • the bracts are hairy, with simple hairs on their outer surface

  Bract outer side hairs

  the bracts are hairy on their outer surfaces

  Bract shape

  the main bracts are linear (long and very narrow)

  Bract spines

  there is just one simple spine at the tip of the bract

  Bract texture

  the bracts appear leathery or hardened

  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 tips of the bracts curve outwards and downwards from the plant

  Bract tip shape

  the tips of the bracts are truncate (end abruptly in a more or less straight line as though cut off)

  Bracts

  the bracts in separate cycles are similar or gradually changing from the outer to inner cycles

  Disk flower color

  blue to purple

  Disk flower lobe number

  5

  Disk flower number

  more than 50

  Disk flower proportions

  • 31-45%
  • 46-75%

  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 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 fine, short hairs on it

  Flower head platform surface

  NA

  Flower head shape

  the flower head is hemispherical (like the bottom half of a sphere)

  Flower type in flower heads

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

  Height of flower head base

  25–40 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

  Ovary attachment

  the ovary is attached at or near the base

  Ovary cross-section

  the ovary is compressed (flattened)

  Ovary hair type

  the ovary has no hairs on it

  Ovary hairs

  the ovary has no hairs on it

  Ovary lines or ribs

  there are no lines or ribs visible on the ovary

  Ovary profile

  • in profile, the ovary is oblong (roughly rectangular but rounded at the ends)
  • 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

  Peduncle length

  10–60 mm

  Peduncle orientation

  the flower heads are held upright, or slightly angled outwards

  Ray flower color

  NA

  Ray flower reproductive parts

  NA

  Ray flowers

  0

  Ray length

  0 mm

  Reproductive system

  all the flowers on the plant contain both carpels and stamens

  Rim at top of ovary

  the central flowers have a disk-shaped platform above the ovary

  Scale tip

  NA

  Smaller bracts at base of bracts

  there is no smaller, outer cycle of bracts

  Width of flower head base

  20–40 mm

• Fruits or seeds

  Number of pappus parts

  11 or more

  Ovary length in developed fruit

  3–4.5 mm

  Seed hair tuft bases

  the pappus hairs are attached to one another near the base

  Seed hair tuft details

  the pappus hairs have smaller hairs along their sides

  Seed hair tuft length

  20–30 mm

  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

  Bract resin

  the bracts have resin or resin glands

  Leaf blade glands

  the leaf blades have no glandular (translucent) dots or scales

  Sap

  the sap is clear and watery

• Growth form

  Growth form

  the plant has one or more free-standing stems

  Horizontal rooting stem

  there are no stolons

  Plant lifespan

  the plant is biennial, it appears as either first year (non-reproductive) plants or second year plants with flowers or fruit

  Spines on plant

  there are spines on the plant

  Underground organs

  there is a thickened taproot on the plant

• Leaves

  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 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 bloom

  the underside of the leaf has no noticeable bloom

  Leaf blade edges

  the edge of the leaf blade has lobes, or it has both teeth and lobes

  Leaf blade flatness

  • the edges of the leaf are curled under
  • 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
  • the leaf blade has tangled or woolly-looking hairs

  Leaf blade length

  150–400 mm

  Leaf blade shape

  • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
  • the leaf blade is oblong (rectangular but with rounded ends)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)

  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 acuminate (tapers to a long, thin point)

  Leaf blade veins

  the leaf blade has one main vein running from the base towards the tip

  Leaf blade width

  60–150 mm

  Leaf disposition

  • the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
  • the lower leaves are larger, toothier, and/or on longer stalks than the upper leaves

  Leaf spines

  there are spines along 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 tufts in axils

  there are no clusters of smaller leaves

  Leaf type

  leaves are simple (i.e., lobed or unlobed but not separated into leaflets)

  Leaflet number

  0

  Specific leaf type

  • the leaf has a row of two or more lobes on each side of the central axis
  • the leaf has a row of two or more lobes on each side of the central axis, and each lobe itself has rows of lobes on each side of the lobe's central axis

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • man-made or disturbed habitats
  • meadows or fields

• 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 point mostly upwards to outwards

  Stem internode hair type

  the hairs on the stem are plain, without glands or branches, and not tangled

  Stem internode hairs

  the stem has hairs between the nodes

  Stem wings

  the stem has wings on it that run down the stem from the leaf nodes

Wetland status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

In New England

From Flora Novae Angliae dichotomous key