Your help is appreciated. We depend on donations to help keep this site free and up to date for you. Can you please help us?

Donate

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

Xanthium spinosum — spiny cocklebur

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

Facts

The origins of spiny cocklebur is not resolved. It may be introduced everywhere north of South America, or it may be native in much of its northern hemisphere distribution. Because of its burs, it probably reached New England mainly as a waste product of the wool-carding industry in the nineteenth century.

Habitat

Anthropogenic (man-made or disturbed habitats)

New England distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America distribution

Adapted from BONAP data

enlarge

Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
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 no teeth or 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
there are spines on the plant
Leaf blade length
40–120 mm
Disk flower number
21-50
Show all characteristics
  • Flowers

    Bases of bract appendages
    NA
    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
    Disk flower color
    • NA
    • white
    Disk flower lobe number
    5
    Disk flower number
    21-50
    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, 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 platform surface
    the scales are slightly hairy, at least near the top
    Flower head position
    • each of the flower heads is separate on its own peduncle (stalk), not clustered in groups
    • some or all the flower heads are grouped in clusters of two or more
    Flower head profile
    • NA
    • the disk is conical across the top
    Flower head shape
    NA
    Flower type in flower heads
    the flower head has disk flowers only, and lacks the strap-shaped flowers
    Height of flower head base
    8–40 mm
    Inflorescence branching (Solidago)
    NA
    Inflorescence shape
    the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
    Ovary beak
    there is a 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 profile
    in profile, the ovary is roughly elliptical (widest in the middle, tapering to both ends)
    Ray flower color
    NA
    Ray flower reproductive parts
    NA
    Ray flowers
    NA
    Ray length
    0 mm
    Reproductive system
    the flowers on the plant may have either carpels or stamens, but always in separate flowers
    Style branch number
    there are no obvious branches on the style
    Width of flower head base
    6–8 mm
  • Fruits or seeds

    Dispersal unit
    the entire flower head falls off or disperses as a unit
    Number of pappus parts
    NA
    Ovary length in developed fruit
    10–15 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
    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
    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
    there are spines on the plant
    Underground organs
    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 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
    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 no teeth or lobes
    • 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
    40–120 mm
    Leaf blade shape
    the leaf blade is lanceolate (lance-shaped; widest below the middle and 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 veins
    the leaf blade has one main vein running from the base towards the tip
    Leaf blade width
    10–50 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
    1–25 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
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    Specific habitat
    man-made or disturbed habitats
  • 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
    • 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

Wetland status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

In New England

Distribution

Connecticut
present
Maine
present
Massachusetts
present
New Hampshire
present
Rhode Island
present
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.  Xanthium spinosum L. E

spiny cocklebur. Acanthoxanthium spinosum (L.) Fourr.; Xanthium spinosum L. var. inerme Bel. • CT, MA, ME, NH, RI. Waste areas, disturbed ground, often in the vicinity of old mills.

Native to North America?

Sometimes confused with

Xanthium strumarium

Family

Asteraceae

Genus

Xanthium