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Native Plant Trust: Go Botany Discover thousands of New England plants

Acanthospermum australe — Paraguay starburr

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Facts

Paraguay starburr is native to South America and introduced in many other parts of the world. It only occurs occasionally in Massachusetts. It can be recognized by its prostrate habit, opposite leaves and five-parted, vaguely star-shaped fruit that adheres to clothing and fur with hooked barbs.

Habitat

Anthropogenic (man-made or disturbed habitats)

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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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
opposite: there are two leaves per node along the stem
Leaf blade edges
  • the edge of the leaf blade has no teeth or lobes
  • the edge of the leaf blade has teeth
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
  • orange
  • yellow
Tuft or plume on fruit
NA
Spines on plant
the plant has no spines
Leaf blade length
13–37 mm
Flower head width
4–6 mm
Disk flower number
  • 1-5
  • 11-20
  • 6-10
Show all characteristics
  • Flowers

    Bases of bract appendages
    NA
    Bract cycle number
    there are two main cycles of bracts
    Bract shape
    • the main bracts are elliptic (widest near the middle and tapered towards the base and tip)
    • the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
    Bract spines
    the bracts are prickly on the outer side
    Bract texture
    • the bracts appear leathery or hardened
    • the bracts have a similar texture to a leaf
    Bracts
    there are at least two distinct forms of bracts in different cycles
    Disk flower color
    yellow
    Disk flower lobe number
    5
    Disk flower number
    • 1-5
    • 11-20
    • 6-10
    Disk flower reproductive parts
    the disk flower has either only pollen- or only 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
    Flower head platform
    the base has papery scales 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 head width
    4–6 mm
    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
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    • NA
    • the flower heads grow in clusters from the axils of the branches or leaves
    Inflorescence stem
    hairs are present on the stem of the inflorescence
    Number of bracts at flower head base
    9–16
    Ovary beak
    there is no beak on the ovary
    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 lines or ribs
    there are four to six lines or ribs visible on the ovary
    Ovary profile
    in profile, the ovary is roughly elliptical (widest in the middle, tapering to both ends)
    Ovary surface
    the ovary surface is textured with tiny points, bumps or wrinkles
    Ray flower color
    • orange
    • yellow
    Ray flower reproductive parts
    the ray flowers have carpels or stamens, but not both
    Ray flowers
    • 1-5
    • 6-10
    Ray length
    Up to 2 mm
    Reproductive system
    all the flowers on the plant contain both carpels and stamens
    Rim at top of ovary
    the central flowers have no disk-shaped platform above the ovary
    Scale tip
    NA
    Style branch number
    the style has one branch
    Width of flower head base
    3–5 mm
  • Fruits or seeds

    Dispersal unit
    the seeds fall off or are dispersed separately from one another
    Number of pappus parts
    0
    Ovary beak length
    0 mm
    Ovary length in developed fruit
    7–9 mm
    Ovary width in developed fruit
    3–5 mm
    Seed hair tuft bases
    NA
    Seed hair tuft color
    NA
    Seed hair tuft details
    NA
    Seed hair tuft length
    0 mm
    Seed hair tuft tips
    NA
    Seed hairs uniform
    NA
    Seed tuft scale number
    0
    Seed tuft type
    there is no pappus on the ovary
    Top of disk flower ovary
    NA
    Tuft or plume on fruit
    NA
  • Glands or sap

    Leaf blade glands
    the leaf blades have glandular (translucent) dots or scales
    Ovary glands
    there are glands on the ovary surface
    Sap
    the sap is clear and watery
  • Growth form

    Growth form
    the plant has one or more free-standing stems
    Horizontal rooting stem
    there are no stolons
    Plant lifespan
    the plant is annual, it lacks evidence of previous years' growth
    Spines on plant
    the plant has no spines
    Underground organs
    • there are only slender roots on the plant
    • there is a thickened taproot 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 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
    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
    Leaf blade edges
    • the edge of the leaf blade has no teeth or 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 hairs with glands at their tips
    Leaf blade length
    13–37 mm
    Leaf blade shape
    • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
    • the leaf blade is triangular, with the stalk or attachment point on one of the sides
    Leaf blade tip
    the tip of the leaf blade is acute (sharply pointed)
    Leaf blade veins
    the leaf blade has one main vein running from the base towards the tip
    Leaf blade width
    7–32 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
    3–15 mm
    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
  • Scent

    Plant odor
    the plant does not have much of an odor
  • 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
    Stem internode hairs
    the stem has no 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

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

1.  Acanthospermum australe (Loefl.) Kuntze E

Paraguay starburr. Melampodium australe Loefl. • MA. Wool waste, gardens, waste areas.

Native to North America?

No

Synonyms

  • Melampodium australe Loefl.

Family

Asteraceae