Xanthium Linnaeus. Common name: Cocklebur.
A genus of about 3-20 or more species, herbs, cosmopolitan (of somewhat uncertain original distribution). A very broad approach to species delineation has been fashionable (see synonymy); we are convinced that the delineation of more taxa (but not an inordinate number) is warranted and does a better job of representing the diversity within the genus. Manzo et al. (2024) studied section Acanthoxanthium, and found a strong basis for recognizing several species.
Key advice:Mature burs are needed for the identification of most species.
References: Cronquist (1980); Fernald (1946); Löve & Dansereau (1959); Manzo et al. (2024); Millspaugh & Sherff (1919); Strother (2006ee) In Flora of North America Editorial Committee (2006b); Tomasello (2018). Show full citations.
Hover over a shape, letter, icon, or arrow on the map for definition or see the legend. Data for arrows not developed for genera and families which may have species only occurring outside the flora area.
© Gary P. Fleming | Xanthium strumarium | Original Image ⭷
© J.W. Hardin | Xanthium strumarium | Original Image ⭷
© Bruce A. Sorrie | Xanthium strumarium | Original Image ⭷Feedback
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