Plants of South Eastern New South Wales
Bidens tripartita
Common name
Burr Marigold, Trifid Burr-marigold
Family
Asteraceae
Where found
Moist and swampy sites and stream banks. Coastal, mainly in the Sydney area. Occasionally elsewhere.
Notes
Introduced perennial woody herb to 1 m high. 'Seeds' with barbs on the awns and the margins of the body of the 'seeds', sticking to clothing. Stems hairless to hairy. Leaves opposite each other, 6–15 cm long, 20–70 mm wide, usually 3-lobed, sometimes 5-lobed or unlobed, margins toothed or shallowly lobed, stalks distinctly winged and stem-clasping. Flower heads hemispherical behind the 'petals', with 1-5 yellow 'petals' when present, and centres 10–25 mm in diameter. Outer bracts around the flower heads leaf-like, to about 40 mm long, often far longer than the florets. Flowering: autumn–winter.
PlantNET description: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Bidens~tripartita (accessed 26 April 2021)
Desecription partly taken from Flora of North America: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200023540 (accessed 26 April 2021)
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