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Native Plant Trust: Go Botany Discover thousands of New England plants

Centaurea benedicta — blessed knapweed

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Facts

Blessed knapweed is a Eurasian native now introduced throughout the world. It is widely cultivated as a medicinal herb, primarily for treating digestive and liver ailments.

Habitat

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

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Massachusetts
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
Leaf blade edges
  • the edge of the leaf blade has lobes, or it has both teeth and lobes
  • the edge of the leaf blade has teeth
Flower type in flower heads
the flower head has disk flowers only, and lacks the strap-shaped flowers
Ray flower color
NA
Tuft or plume on fruit
there is no plume, or the plume is made up of scales, awns, a crown, or a rim
Spines on plant
  • the plant has no spines
  • there are spines on the plant
Leaf blade length
60–250 mm
Disk flower number
more than 50
Show all characteristics
  • Flowers

    Bract color
    the bracts are colored, or at least tinged with, pink, red or purple
    Bract cycle number
    there are three or more cycles of bracts
    Bract shape
    • the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
    • the main bracts are ovate (egg-shaped)
    Bract spines
    there is one spine with branches, at the tip of the bract
    Bract texture
    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 extension appearance
    the projections from the bract tips have further projections from their edges, like a fringe
    Bract tip extension edge
    there are projections from the bract tips
    Bract tip orientation
    the tips of the bracts curve outwards and downwards from the plant
    Bracts
    the bracts in separate cycles are similar or gradually changing from the outer to inner cycles
    Disk flower color
    yellow
    Disk flower lobe number
    • 3
    • 5
    Disk flower number
    more than 50
    Disk flower reproductive parts
    • the disk flower has both pollen- and seed-producing parts
    • the disk flower has no reproductive parts
    Flower head number
    each flowering stem has only one to three flower heads on it
    Flower head outer flowers
    at the outer edge of the flower head, the flowers have no enlarged lobe or strap, but are bigger than the flowers in the center of the disk
    Flower head platform
    the base has fine, short hairs on it
    Flower head platform surface
    NA
    Flower head position
    each of the flower heads is separate on its own peduncle (stalk), not clustered in groups
    Flower head profile
    the disk is flat or nearly flat across the top
    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
    20–40 mm
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    NA
    Inflorescence stem
    NA
    Ovary attachment
    the ovary is attached at the side near the base, rather than at the base
    Ovary beak
    there is no beak on the ovary
    Ovary cross-section
    the ovary has five or more corners in cross-section
    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 ten or more ribs visible on the ovary
    Ovary profile
    in profile, the ovary is oblong (roughly rectangular but rounded at the ends)
    Peduncle length
    At least 0 mm
    Ray flower color
    NA
    Ray flower reproductive parts
    NA
    Ray flowers
    0
    Reproductive system
    all the flowers on the plant contain both carpels and stamens
    Scale tip
    NA
    Smaller bracts at base of bracts
    there is no smaller, outer cycle of bracts
    Style branch number
    the style has two branches
    Width of flower head base
    20–25 mm
  • Fruits or seeds

    Ovary length in developed fruit
    8–11 mm
    Ovary width in developed fruit
    2.7–3.2 mm
    Seed hair tuft color
    • the pappus hairs are another color
    • the pappus hairs are tan to dark brown
    Seed hair tuft length
    2–10 mm
    Seed hair tuft tips
    the pappus hairs are slender
    Seed hairs uniform
    there are two distinct lengths of pappus hairs
    Seed tuft scale number
    0
    Seed tuft type
    the pappus is made of stiff, tapering bristles
    Top of disk flower ovary
    NA
    Tuft or plume on fruit
    there is no plume, or the plume is made up of scales, awns, a crown, or a rim
  • Glands or sap

    Leaf blade glands
    the leaf blades have 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
    Plant lifespan
    the plant is annual, it lacks evidence of previous years' growth
    Spines on plant
    • the plant has no spines
    • there are spines 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 edges
    • the edge of the leaf blade has lobes, or it has both teeth and lobes
    • the edge of the leaf blade has teeth
    Leaf blade hairs
    • the leaf blade has hairs with glands at their tips
    • 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
    60–250 mm
    Leaf blade shape
    • 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)
    Leaf blade tip
    the tip of the leaf blade is acute (sharply pointed)
    Leaf blade width
    20–60 mm
    Leaf disposition
    the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
    Leaf stalk
    • the leaves have leaf stalks
    • the leaves have no leaf stalks, but attach directly to the stem
    Leaf tip extension
    NA
    Leaf type
    leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Specific leaf type
    the leaf has a row of two or more lobes on each side of the central axis
  • Place

    Habitat
    terrestrial
    New England state
    • Connecticut
    • Massachusetts
    Specific habitat
    • man-made or disturbed habitats
    • meadows or fields
  • 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
    at least some of the hairs on the stem are tangled, matted or woolly
    Stem internode hairs
    the stem has hairs between the nodes
    Stem wings
    the stem does not have wings on it

Wetland status

Not classified

In New England

Distribution

Connecticut
present
Maine
absent
Massachusetts
present
New Hampshire
absent
Rhode Island
absent
Vermont
absent

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Massachusetts
not applicable (S-rank: SNA)

From Flora Novae Angliae dichotomous key

1.  Centaurea benedicta (L.) L. E

blessed knapweed. Cnicus benedictus L. • CT, MA. Roadsides, fields, waste areas.

Native to North America?

No

Synonyms

  • Cnicus benedictus L.

Family

Asteraceae

Genus

Centaurea