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- Asteraceae
- Asteraceae Group 6
- Helenium
- Helenium amarum
Helenium amarum — narrow-leaved sneezeweed
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Facts
Narrow-leaved sneezeweed's range includes much of the East, Midwest and South, but although it can be weedy in some places, this species is rarely adventive in New England.
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.
Found this plant? Take a photo and post a sighting.
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 no teeth or lobes
- Flower type in flower heads
- the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery
- Ray flower color
- yellow
- 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
- Leaf blade length
- 15–80 mm
- Disk flower number
- more than 50
-
Flowers
- Bract cycle number
-
- there are three or more cycles of bracts
- there are two main cycles of bracts
- there is one main cycle of bracts
- Bract outer side hair type
- the bracts are hairy, with simple hairs on their outer surface
- Bract outer side hairs
- the bracts are hairy on their outer surfaces
- Bract separation
-
- at least some flower heads have bracts connected to one another at or near their bases
- the bracts appear completely unconnected to one another on all flower heads
- Bract texture
- the bracts have a similar texture to a leaf
- 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
-
- blue to purple
- green to brown
- yellow
- Disk flower lobe number
- 5
- Disk flower number
- more than 50
- Disk flower reproductive parts
- the disk flower has both pollen- and seed-producing parts
- Disk width
- 6–12 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, each flower has a single enlarged lobe or strap
- Flower head platform
- the base has no bristles or papery scales
- Flower head platform surface
- NA
- Flower head profile
- the disk is conical across the top
- Flower type in flower heads
- the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery
- Height of flower head base
- 5–9 mm
- Inflorescence stem
- the stem of the inflorescence is not hairy
- 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
- Ovary hairs
- the ovary has hairs on it
- Ovary lines or ribs
- there are four to six lines or ribs visible on the ovary
- Peduncle length
- 30–100 mm
- Ray flower color
- yellow
- Ray flower reproductive parts
- the ray flowers have carpels or stamens, but not both
- Ray flowers
- 6-10
- Ray length
- 4.5–14 mm
- Reproductive system
- some of the flowers on the plant have only carpels or stamens, while others have both carpels and stamens
- Scale tip
- NA
- Smaller bracts at base of bracts
- there is a cycle of much smaller bracts outside the cycle of larger and longer bracts
- Style branch number
- the style has two branches
- Style branches
- the style branch is wider at the tip and has a flattened end, or the style branches are wider at the tips and have flattened ends
-
Fruits or seeds
- Number of pappus parts
-
- 10
- 5
- 6
- 7
- 8
- 9
- Ovary length in developed fruit
- 0.7–1.3 mm
- Seed hair tuft bases
- NA
- Seed hair tuft color
- NA
- Seed hair tuft details
- NA
- Seed hair tuft length
- 1–1.8 mm
- Seed hair tuft tips
- the pappus hairs are slender
- Seed hairs uniform
- NA
- Seed tuft scale number
- 5–10
- Seed tuft type
- the pappus is made of flat scales that are not split or frayed at the tips
- 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
- Bract resin
- the bracts have resin or resin glands
- Leaf blade glands
- the leaf blades have glandular (translucent) dots or scales
-
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
- Underground organs
- there is a thickened taproot on the plant
-
Leaves
- Hairs on underside of leaf blade
-
- the underside of the leaf is fuzzy or hairy
- the underside of the leaf is not hairy, or has very few hairs
- 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 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 no teeth or lobes
- Leaf blade hairs
- the leaf blade has simple hairs with no glands, and not tangled or wooly
- Leaf blade length
- 15–80 mm
- Leaf blade shape
-
- the leaf blade is filiform (extremely narrow, thread-like)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade tip
- the tip of the leaf blade is acute (sharply pointed)
- Leaf blade width
- 1–4 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 no leaf stalks, but attach directly to the stem
- 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
- the leaf has lobes that themselves have lobes, and these secondary lobes also have lobes; there may be more than three levels of lobes
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- 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 type
-
- 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 does not have wings on it
Wetland status
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
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.
var. amarum
- Massachusetts
- not applicable (S-rank: SNA)
Subspecies and varieties
Our variety is Helenium amarum (Raf.) H. Rock var. amarum.
From Flora Novae Angliae dichotomous key
1. Helenium amarum (Raf.) H. Rock var. amarum E
narrow-leaved sneezeweed. Helenium tenuifolium Nutt. • CT, MA. Fields, roadsides, waste areas.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Helenium autumnale:
- leaves decurrent on the stems and branches, with blades wider than 5 mm, and plants perennial (vs. H. amarum, with leaves not decurrent on stems and branches, with blades narrower than 5 mm, and plants annual).
Synonyms
- Helenium tenuifolium Nutt.