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- Bidens pilosa
Bidens pilosa — hairy beggar-ticks
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Facts
Hairy beggar-ticks is native to tropical America, and has become a major weed and pest species worldwide. It can form dense stands and its seeds contaminate food crops. Furthermore, it is a host and vector for crop diseases such as root knot nematode (Meloidogyne sp.) and tomato spotted wilt virus (Schlerotinia sclerotiorum).
Habitat
Anthropogenic (man-made or disturbed habitats)
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
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- opposite: there are two leaves 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
- the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery
- Ray flower color
-
- white
- 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
- 30–120 mm
- Flower head width
- 5–15 mm
- Disk flower number
-
- 11-20
- 21-50
- more than 50
-
Flowers
- Bases of bract appendages
- NA
- Bract cycle number
- there are two main cycles of bracts
- Bract margins
- there are fine hairs along the bract margins
- 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 shape
-
- the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
- the main bracts are linear (long and very narrow)
- the main bracts are oblanceolate (widest near the tip, but otherwise narrow and tapering)
- the main bracts are of a different shape than the given options
- Bract spines
- the bracts have no spines
- Bract texture
-
- the bracts appear thin, flexible and nearly translucent
- the bracts have a similar texture to a leaf
- Bract tip orientation
- the bracts are pressed against the plant, or spreading out at the tips
- Bracts
- there are at least two distinct forms of bracts in different cycles
- Disk flower color
- yellow
- Disk flower lobe number
-
- 3
- 4
- 5
- Disk flower number
-
- 11-20
- 21-50
- more than 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 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
- 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 papery scales on it
- 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
- the disk is rounded across the top
- Flower head shape
-
- the flower head is shaped like a cone with the point up
- the sides of the flower head are roughly parallel, like a cylinder
- Flower head width
- 5–15 mm
- Flower type in flower heads
-
- the flower head has disk flowers only, and lacks the strap-shaped flowers
- 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
- 5–6 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
-
- NA
- the inflorescence is flat-topped in profile
- Number of bracts at flower head base
- 13–26
- Ovary beak
- there is no beak on the ovary
- Ovary cross-section
-
- the ovary is compressed (flattened)
- the ovary is roughly square or with four corners
- Ovary hair type
- the ovary has hairs on it, but the hairs have no glands
- Ovary hairs
- the ovary has hairs on it
- Ovary profile
-
- in profile, the ovary is another shape
- in profile, the ovary is very narrow
- Ovary surface
- the ovary surface is textured with tiny points, bumps or wrinkles
- Peduncle length
- 10–90 mm
- Ray flower color
-
- white
- yellow
- Ray flower reproductive parts
- there are neither carpels nor stamens in the ray flowers
- Ray flowers
-
- 0
- 1-5
- 6-10
- Ray length
- 0–5 mm
- Reproductive system
- all the flowers on the plant contain both carpels and stamens
- Scale tip
- the scales are blunt, with a terminal notch, or straight across the top
- 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
- 6–8 mm
-
Fruits or seeds
- Number of pappus parts
-
- 2
- 3
- 4
- 5
- Ovary beak length
- 0 mm
- Ovary length in developed fruit
- 3–16 mm
- Seed hair tuft details
- the pappus hairs are hooked or barbed
- Seed hair tuft length
- 0–4 mm
- Seed hair tuft tips
- the pappus hairs are slender
- Seed hairs uniform
- all the pappus hairs are approximately the same length
- Seed tuft scale number
- 0
- Seed tuft type
- the pappus is made of stiff, tapering bristles
- Top of disk flower ovary
- the top of the ovary in fruit is flattened
- 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 no 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 annual, it lacks evidence of previous years' growth
- 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
- there is a thickened taproot on the plant
-
Leaves
- Final leaf segment length (compound lvs only)
- 10–80 mm
- Final leaf segment width (compound lvs only)
- 5–40 mm
- 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 fuzzy or hairy
- the upper side of the leaf is not hairy, or has very few hairs
- Leaf arrangement
- opposite: there are two leaves per node along the stem
- Leaf blade base
- the leaf has a distinct 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
- the base of the leaf blade is truncate (ends abruptly in a more or less straight line as though cut off)
- 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 flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- the leaf blade has simple hairs with no glands, and not tangled or wooly
- Leaf blade length
- 30–120 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 tip
-
- the tip of the leaf blade is acuminate (tapers to a long, thin point)
- the tip of the leaf blade is acute (sharply pointed)
- Leaf blade width
- 12–45 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
- Leaf stalk length
- 10–70 mm
- 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
- Specific habitat
- man-made or disturbed habitats
-
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
- NA
- Stem internode hair length
- 0 mm
- Stem internode hair type
- the stem has no hairs between the nodes
- Stem internode hairs
- the stem has no hairs between the nodes
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- absent
- 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.
- Massachusetts
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
12. Bidens pilosa L. E
hairy beggar-ticks. Bidens odorata Cav.; B. pilosa L. var. minor (Blume) Sherff • CT. Ballast, waste areas.
Native to North America?
Yes
Sometimes confused with
Synonyms
- Bidens odorata Cav.
- Bidens pilosa L. var. minor (Blume) Sherff