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 - Centaurea benedicta
 
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
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
 
 
- Leaf type
 - leaves are simple (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
 
- 
                        
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 (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
None
From Flora Novae Angliae dichotomous key
1. Centaurea benedicta (L.) L. E
blessed knapweed. Cnicus benedictus L. • CT, MA. Roadsides, fields, waste areas.