A North American species found in the tall grass prairie and disturbed sites, Chamaecrista has been used in studies of ecology and legume evolution. Partridge pea represents an early-diverging lineage among the legumes, but it has nitrogen-fixing nodules, unlike many other "basal" species.


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Image Source: http://www.delawarewildflowers.org/images/chamaecrista_fasciculata.jpg