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- Carduus
- Carduus crispus
Carduus crispus — curly plumeless-thistle
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Facts
Curly plumeless-thistle is often confused with the far more common spiny plumeless thistle (Carduus acanthoides), but the two species differ in several respects. Native to Eurasia, in North America it is a weed of roadsides, waste areas and pastures.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
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.
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Characteristics
- Habitat
- terrestrial
- New England state
-
- Rhode Island
- 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 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
- at least a part of the plume is made up of fine bristles
- Spines on plant
- there are spines on the plant
- Leaf blade length
- 100–200 mm
- Flower head width
- 15–18 mm
- Disk flower number
- more than 50
-
Flowers
- Bract cycle number
- there are three or more cycles of bracts
- Bract outer side hair type
- the bracts are hairy on their outer surfaces, with curled, tangled, matted, or woolly hairs
- Bract shape
- the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
- Bract spines
- there is just one simple spine at the tip of the bract
- Bract tip extension appearance
- the projections from the bract tips are simple, but may be a different color than the bract
- Bract tip extension edge
- there are 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)
- Disk flower color
-
- blue to purple
- pink to red
- white
- Disk flower number
- more than 50
- Disk flower shape
- the disk flower is abruptly widened at some point below the lobes
- Disk width
- 15–18 mm
- Flower head number
-
- each flowering stem has four or more flower heads on it
- 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, 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 position
- some or all the flower heads are grouped in clusters of two or more
- Flower head profile
-
- the disk is conical across the top
- 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
- 15–18 mm
- Flower type in flower heads
- the flower head has disk flowers only, and lacks the strap-shaped flowers
- Height of flower head base
- 12–17 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
-
- NA
- the inflorescence is flat-topped in profile
- Ovary attachment
- the ovary is attached at the side near the base, rather than at 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 four to six lines or ribs visible on the ovary
- there are no lines or ribs visible on the ovary
- there are ten or more ribs visible on the ovary
- Ovary profile
- 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
- Up to 100 mm
- 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
- 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
- 10–25 mm
-
Fruits or seeds
- Ovary length in developed fruit
- 2.5–3.8 mm
- Seed hair tuft bases
- the pappus hairs are 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
- 11–13 mm
- 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
- 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 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
-
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
- 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 lobes, or it has both teeth and lobes
- the edge of the leaf blade has teeth
- Leaf blade hairs
- the leaf blade has tangled or woolly-looking hairs
- Leaf blade length
- 100–200 mm
- Leaf blade surface colors
- there is no noticeable color variation on the upper surface of the leaf
- 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 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
- 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
-
- Rhode Island
- Vermont
- 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
-
- at least some of the hairs on the stem are tangled, matted or woolly
- 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 has wings on it that run down the stem from the leaf nodes
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- absent
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- present
Conservation status
None
From Flora Novae Angliae dichotomous key
2. Carduus crispus L. E
curly plumeless-thistle. RI, VT. Roadsides, fields, pastures. The distribution of Carduus crispus has long been erroneous due to reliance on non-diagnostic characters. Keil (2006b) presented C. crispus as the more widespread species in New England, but this is incorrect. Carduus acanthoides is more frequent and is responsible for most reports of C. crispus in New England.
Native to North America?
No
Sometimes confused with
- Carduus acanthoides:
- undersurface of leaves with only type of hair: curling and septate (vs. C. crispus, with the undersurface of leaves with two types of hairs: longer, curling, septate hairs on the veins and sparse, woolly hairs in between).