Bidens frondosa Linnaeus

Remark The words or terms in red (actually dark orange) in the text are defined in a glossary.


aug_13_11c.gthmb can't be loaded. Bidens frondosa is a herbaceous plant native to North America where it is widely distributed. In the U.S., is it one of the most widely distributed and annoying weeds, thanks to its achenes which are readily carried from place to place in the hair or fur of animals, especially sheep. The achenes also stick readily to the clothes of passersby becoming a real nuisance in early autumn.

The plant belongs to the Asteraceae family.

Name

In Latin, bis means twice and dens means tooth so that bidens means two-toothed; hence the genus name refers to the bristles achenes of the plant, even if these seeds have, at times, three or four bristles.

In Latin, frondosus means covered with leaves and is not that much of a qualifying epithet since Bidens frondosa has no more and no less leaves than than other Bidens species.

Common names

Some of the vernacular names of Bidens frondosa are: Devils Beggarticks, Common Bur-Marigold, Bur Marigold, Devil's Bootjack, Devil's Pitchfork, Devil's Beggartick, Devils Beggartick, Sticktights, Tickseed Sunflower, Largeleaf Beggarticks, Old Ladies' Clothespins, Pitchfork Weed and Sticktight. Some of its French vernacular names are: Bidens feuillu, Bident feuillé and Bident à fruits noirs.

Synonyms

Bidens frondosa has also been known as:

Identification

Bidens are well known for taxonomic taxonomic difficulty, the species having plastic phenotypes. Bidens frondosa is identified by : Bidens frondosa resembles Bidens pilosa with generally similar characters, but the achenes of the later are longer, more slender and four-angled.

Bidens frondosa also resembles Bidens cernua (when the later has no ray florets) except that the leaves of the former are long-stalked and divided into 3 or 5 sharply toothed leaflets, and the achenes have two awns. draw_01.jpg can't be loaded.

Description

Bidens frondosa is an erect annual with a taproot that branches frequently.

Stems

Leaves

Flower heads

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Fruits

Habitat

Bidens frondosa is found on moist areas of black soil prairies, in moist meadows near woodlands or rivers, in floodplain woodlands and young flatwoods, in thickets, marshes, swamps, seeps, and borders of ponds or lakes, in low-lying areas along railroads and roadsides, in both cultivated and abandoned fields, in drainage ditches and miscellaneous waste areas. This plant likes disturbed areas.

Distribution

map_na.jpg can't be loaded. Bidens frondosa can be found in most of the USA States and in all Canadian provinces; it is not found (for the time being) in Montana, and Alaska, nor in the Canadian territories. In Europe, it is established in Sicily, in peninsular Italy, and in Germany. The map shows the USA States and Canadian provinces where Bidens frondosa can be found.

Notes

Bidens frondosa is eaten by muskrats (Ondatra zibethicus) and the achenes are eaten by ducks. Infusions and tinctures of Bidens frondosa are rated as outstanding herbal therapies for irritation, inflammation, pain, and bleeding of the urinary tract mucosa and are used for benign prostatic hypertrophy and increasing excretion of uric acid, decreasing the risk of gout attacks, as well as other medical uses.

Gallery

The photos of the gallery were taken either with one of the following: The title in the window shows the date when the picture was taken, i.e. jan_30_06... would mean that the photo was taken on the 30th of January, the 06 is for the 6th picture taken that day.

The month, day and picture number might be followed by a letter:

Click on the thumbnails to get larger view. The original photos are usually in TIFF format, the photos shown are generally in JPEG format, usually of dimensions one half (surface one quarter) for loading time reduction.

Plants

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Leaves

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Flowers

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Fruits, seeds

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