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- Vernonia glauca
Vernonia glauca — broad-leaved ironweed
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Facts
Broad-leaved ironweed is an eastern species whose native range begins well south of New England. It may very occasionally escape from gardens, where it is grown as an ornamental. The Cherokee used broad-leaved ironweed as an analgesic, and as a treatment for stomach ulcers.
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
- 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 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
- 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
- Leaf blade length
- 100–180 mm
- Disk flower number
- 21-50
-
Flowers
- Bases of bract appendages
- NA
- 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 margins
- there are fine hairs along the bract margins
- Bract outer side hair type
- the bracts are hairy on their outer surfaces, with curled, tangled, matted, or woolly hairs
- Bract outer side hairs
-
- the bracts are hairy on their outer surfaces
- the bracts are not hairy on their outer surfaces
- Bract shape
-
- the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
- the main bracts are of a different shape than the given options
- Bract spines
- the bracts have no spines
- Bract tip color
- the tips are the same color as the center of the bract
- Bract tip extension appearance
- NA
- Bract tip extension edge
- NA
- Bract tip orientation
- the bracts are pressed against the plant, or spreading out at the tips
- Bract tip shape
- the tips of the bracts are acuminate (tapered to a narrow point)
- Disk flower color
-
- blue to purple
- pink to red
- white
- Disk flower number
- 21-50
- Disk flower reproductive parts
- the disk flower has both pollen- and seed-producing parts
- Disk flower shape
- the disk flower is tube-shaped (cylindrical), or gradually widening like a funnel
- Flower head number
- each flowering stem has four or more 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 no bristles or papery scales
- 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 flat or nearly flat across the top
- the disk is rounded 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
- 5–8 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
- Number of bracts at flower head base
- 40–60
- 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 hairs on it, but the hairs have no glands
- the ovary has no hairs on it
- Ovary hairs
-
- the ovary has hairs on it
- the ovary has no hairs on it
- Ovary lines or ribs
-
- there are seven to nine ribs visible on the ovary
- 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
- 2–35 mm
- Ray flower color
- NA
- Ray flower reproductive parts
- NA
- Ray flowers
- NA
- 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
- Style branches
- the style branch is narrow at the tip, or the style branches are narrow at the tips
- Width of flower head base
- 7–8 mm
-
Fruits or seeds
- Number of pappus parts
- 11 or more
- Ovary length in developed fruit
- 3–4 mm
- Seed hair tuft color
-
- the pappus hairs are tan to dark brown
- the pappus hairs are white or off-white
- Seed hair tuft length
- 0.5–8 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
- 40–70
- Seed tuft type
- the pappus is made of flat scales that are not split or frayed at the tips
- Top of disk flower ovary
- NA
- Tuft or plume on fruit
-
- at least a part of the plume is made up of fine bristles
- 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
- the leaf blades have no glandular (translucent) dots or scales
- Ovary glands
-
- there are glands on the ovary surface
- there are no visible glands on the ovary
- Sap
- NA
-
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
- the plant has no spines
- 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
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment width (compound lvs only)
- 0 mm
- 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
- 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 teeth
- Leaf blade hairs
- the leaf blade has simple hairs with no glands, and not tangled or wooly
- Leaf blade length
- 100–180 mm
- Leaf blade shape
-
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- 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
- 30–70 mm
- Leaf disposition
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaf spines
- there are no spines on 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 (lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets
-
Place
- Habitat
- terrestrial
- New England state
- Massachusetts
- 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
- the hairs on the stem are plain, without glands or branches, and not tangled
- Stem internode hairs
- the stem has hairs between the nodes
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
2. Vernonia glauca (L.) Willd. E
broad-leaved ironweed. Serratula glauca L. • MA. Fields, roadsides, waste areas.