Bidens pilosa
species of plant

Bidens pilosa is an annual species of herbaceous flowering plant in the daisy family Asteraceae. Its many common names include hitch hikers, black-jack, beggarticks, farmer's friends and Spanish needle, but most commonly referred to as cobblers pegs. It is native to the Americas but is widely distributed as an introduced species in other regions including Eurasia, Africa, Australia, South America and the Pacific Islands, and is classified as an invasive species in some regions of the world.
Description
Bidens pilosa is a branched annual forb of gracile habit, growing up to 1.8 meters (5 ft 11 in) tall. It grows aggressively on disturbed land and often becomes weedy. The leaves are all oppositely arranged and range from simple to pinnate in form, the upper leaves with three to five dentate, ovate-to-lanceolate leaflets. The petioles are slightly winged.
The plant may flower at any time of the year, but mainly in summer and autumn in temperate regions. The flowers are small heads borne on relatively long peduncles. The heads consist of about four or five broad white ray florets (ligules), surrounding many tubular yellow disc florets without ligules that develop into barbed fruits.
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Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Aug 21, 2026. The linked authority identifier is Q814421. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Bidens pilosa” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.