Summary ³

Bidens pilosa is a species of flowering plant in the aster family. It is native to the Americas but it is known widely as an introduced species of other regions, including Eurasia, Africa, Australia, and the Pacific Islands. It is a tall branched weed with thin yellow flowers that develop into a cluster of barbed seeds. Its many common names include black-jack, beggar-ticks, cobbler's pegs, and Spanish needle. The seeds are like short, stiff hairs. They..

Description ⁴

Annual herb to 1.5 (-2.2) m. Leaves petiolate, (1-)3-foliolate, glabrous or pilose. Terminal leaflet up to 9 × 5 cm, narrowly ovate to ovate-oblong; base cuneate; apex acuminate; margin ciliate, crenate or serrate-crenate; lateral leaflets smaller, asymmetric. Inflorescence laxly corymbose. Capitula up to 1 cm in diameter. Rays 0 (var. pilosa) or creamy-white, 4-7 and up to 1.5 cm, exceeding (var. radiata Sch.Bip.) or not exceeding (var. minor Blume) the phyllaries. Achenes up to 1.6 cm, blackish. Bristles 2-3, retrorsely barbed.

Sources and Credits

1. (c) harum.koh, some rights reserved (CC BY-SA), uploaded by harum.koh, https://www.flickr.com/photos/harumkoh/22122999324/
2. (c) colinmorita, some rights reserved (CC BY-NC), uploaded by colinmorita
3. (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Bidens_pilosa
4. (c) Mark Hyde, Bart Wursten and Petra Ballings, some rights reserved (CC BY-NC), http://eol.org/data_objects/30290527

More Info

• iNat taxon page
• African Plants - a photo guide
• Atlas of Living Australia
• Biodiversity Heritage Library
• BOLD Systems BIN search
• Catalogo de Plantas y Líquenes de Colombia
• eFloras.org
• Flora Digital de Portugal
• Flora of North America (beta)
• Global Biodiversity Information Facility (GBIF)
• HOSTS - a Database of the World's Lepidopteran Hostplants
• IPNI (with links to POWO, WFO, and BHL)
• NatureServe Explorer 2.0
• NBN Atlas
• New Zealand Plant Conservation Network
• SEINet Symbiota portals
• Tropicos
• VASCAN by Canadensys
• World Flora Online
• 日本のレッドデータ検索システム
• 植物和名−学名インデックス YList

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