SafePlants

Beggar-Ticks (Bidens spp.)

Beggar-ticks are wildflowers belonging to the genus Bidens. Several species bloom late in the summer.

Common Names

• Beggarticks
• Black Jack
• Bur Marigolds
• Cobbler's Pegs
• Spanish Stickseeds
• Tickseeds
• Tickseed Sunflowers
• Devil's Beggartick
• Spanish Needles
• Stickright
• Devil's Large Beggarticks

These common names often refer to the plant's fruits.

Taxonomy and Nomenclature

• Genus: Bidens
• Family: Asteraceae (also known as Compositae)
• Species Examples:
  • Bidens frondosa (beggar-ticks)
  • Bidens macrocarpa (Large-fruit Beggarticks) - Accepted scientific name; taxonomic status: Accepted.
  • Bidens cernua (Nodding Beggarticks or Common Beggartick)
  • Bidens pilosa (Hairy Beggarticks)
  • Bidens coronata (Large-fruit Beggarticks)
  • Bidens amplissima (Vancouver Island Beggarticks)
  • Bidens ferulifolia (Fern-leaved Beggar-ticks)
  • Bidens aurea (Apache Beggarticks, Bur Marigold)

Synonyms

• Bidens tripartita species: European beggar-ticks, trifid bur

Distribution and Habitat

• Hairy beggar-ticks (Bidens pilosa) is native to tropical America.
• European beggar-ticks (Bidens tripartita) is native to large parts of the Northern Hemisphere, including Europe and the Indian.
• Found in various habitats including:
  • Rice fields
  • Canals
  • Forests
  • Pasture fields
  • Fruit gardens
  • Riversides
  • Swamps
  • Farm areas
  • Moist bottomlands
  • Tidal river systems

Ecological Role

• Hairy beggar-ticks (Bidens pilosa) has become a major weed.
• Some Bidens species can be particularly disagreeable weeds due to the barbed awns on their fruit.

Morphological Characteristics

• Annual or perennial herbaceous plants. Some species can develop into quite large plants if grown as perennials.
• Some species are erect, arising from a taproot.
• Flowers:
  • Most Bidens have large heads of both disc and ray flowers.
  • Some flowers lack the large yellow ray florets.
  • Some species, like Bidens aequisquama, have showy flowers.
  • Nodding Beggarticks (Bidens cernua) has large flower heads that tend to droop.
• Fruits (Achenes):
  • Seed heads are round, larger than flower disks, and covered in flat, dark seeds.
  • Fruits are flat, sometimes 4-edged, and taper to a narrow base.
  • Achenes are dark-colored, sometimes olive green to brown.
  • Some have descending bristles along the edges.
  • Fruits have barbs or prickles to cling to fur and clothing.
  • Some species have needlelike awns that attach themselves to clothing and pets.
  • Some species lack a plume or have a plume made up of scales or awns.
• Leaves:
  • Nodding Beggarticks (Bidens cernua) is distinguished by its opposite undivided leaves.