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- Asteraceae Group 2
- Cirsium
- Cirsium altissimum
Cirsium altissimum — tall thistle
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Facts
A native biennial of the United States, the natural range of tall thistle probably does not extend to New England. The Cherokee used the down to make the tails of blow darts, and an infusion of the roots to treat overeating.
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
-
- Connecticut
- Massachusetts
- 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
- 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 no teeth or lobes
- Flower type in flower heads
- the flower head has disk flowers only, and lacks the strap-shaped flowers
- 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
- 100–400 mm
- Disk flower number
-
- 21-50
- more than 50
-
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
- Bract outer side hair type
- the bracts are hairy on their outer surfaces, with hairs having glands (a swelling at the tip of the hair)
- Bract outer side hairs
-
- the bracts are hairy on their outer surfaces
- the bracts are not hairy on their outer surfaces
- Disk flower number
-
- 21-50
- more than 50
- Flower head platform
- the base has fine, short hairs on it
- Flower type in flower heads
- the flower head has disk flowers only, and lacks the strap-shaped flowers
- Height of flower head base
- 20–50 mm
- 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 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
- Ray flowers
- 0
- Reproductive system
-
- all the flowers on some plants have carpels, while all the flowers on other plants have stamens
- some of the flowers on the plant have only carpels or stamens, while others have both carpels and stamens
- Rim at top of ovary
- the central flowers have a disk-shaped platform above the ovary
- Smaller bracts at base of bracts
- there is a cycle of much smaller bracts outside the cycle of larger and longer bracts
-
Fruits or seeds
- Ovary length in developed fruit
- 4–5.5 mm
- 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
- Plant lifespan
- the plant is perennial, it shows evidence of previous year's leaves, stems or stem bases
- Spines on plant
- there are spines on the plant
- Underground organs
-
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
- there are only slender roots 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 not hairy, or has very few hairs
- 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 no teeth or lobes
- Leaf blade hairs
- the leaf blade has tangled or woolly-looking hairs
- Leaf blade length
- 100–400 mm
- Leaf blade shape
-
- the leaf blade is elliptic (widest near 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)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade veins
- the leaf blade has one main vein running from the base towards the tip
- Leaf blade width
- 10–60 mm
- Leaf disposition
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- 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
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Massachusetts
- 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
- the hairs are pressed flat against the plant, pointing either towards the plant's tip or towards it's base
- Stem internode hair type
-
- at least some of the hairs on the stem have glands
- 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
Not classified
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- unranked (S-rank: SNR)
- Vermont
- extremely rare (S-rank: S1)
From Flora Novae Angliae dichotomous key
1. Cirsium altissimum (L.) Spreng. E
tall thistle. Carduus altissimus L. • CT, MA, VT. Fields, roadsides, disturbed soil.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Cirsium discolor:
- stem leaf blades with revolute margins and evident narrow lobes, and tips of innermost involucral bracts slender, not dilated, and entire (vs. C. astissimum, with stem leaf blades with flat margins, unlobed or with short lobes, and tips of innermost involucral bracts dilated and erose to serrulate).
- Cirsium flodmanii:
- leaf blades usually thinly tomentose on the adaxial surface, stem uniforny and persistently tomentose, and pappus bristles 20-30 mm long (vs. C. altissimum, with leaf blades glabrate or sparsely villous on the adaxial surface, stems glabrate or with some tomentum near the apex, and pappus bristles 12-24 mm long).
Synonyms
- Carduus altissimus L.