Nodding Beggarticks (Bidens cernua) Linnaeus, 1753 |
Synonyms: Bidens filamentosa, Bidens glaucescens, Bidens gracilenta, Bidens minima, Bidens prionophylla (see The Plant List for more synonyms), nodding bur-marigold |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
Bidens cernua is an annual herb widely distributed across the Northern Hemisphere. In Eurasia, it occurs from Scandinavia to the Mediterranean, and east to the Himalayas. In North America, this species is found throughout most of the United States and southern Canada. Nodding Beggarticks grows in nutrient-rich mud on the margins of swamps, marshes, bogs, in dry beaver ponds, seeps, wet meadows, riverbanks, and ditches. It may form large colonies, but is usually scattered; from sea level to 2,300 m. Bidens cernua usually grows 20-100 cm tall. Stems are hairless or sparsely hairy, green or reddish. The leaves are oblong to lanceolate, serrated along the margins. Flower heads erect or nodding, with 8 oval yellow petals with a notch at the tip. It flowers from August to October. Seeds (achenes) are dark brown, with 4 barbed awns that attach the seed to anything that brushes against it (fur or clothes).