ironweed

Vernonia setosquamosa is a perennial herb or subshrub in the family Asteraceae, belonging to the genus Vernonia, commonly known as ironweeds. The genus Vernonia in its broad traditional sense encompassed over 1,000 species distributed across tropical and subtropical regions of Africa, the Americas, and Asia, though modern molecular studies have led to the recognition of numerous segregate genera. The epithet 'setosquamosa' combines Latin 'seta' (bristle) and 'squama' (scale), suggesting that this species bears bristle-tipped or setose phyllary scales, a feature that aids in species identification within the genus. Ironweeds are characterized by discoid capitula bearing exclusively purple to reddish-purple tubular florets, lacking ray florets entirely. The involucre phyllaries are imbricate in multiple rows and may be appressed, spreading, or with elongated appendages. The pappus consists of an outer ring of short scales and an inner ring of long capillary bristles. Achenes are ribbed or angled. Vernonia species typically inhabit open habitats including grasslands, savannas, shrublands, forest margins, and disturbed ground. Their distribution and ecology vary enormously across the genus's wide geographic range. African Vernonia species often occur in savanna and woodland habitats, while American ironweeds inhabit tallgrass prairies and moist meadows. The species is likely native to tropical Africa or Asia based on the generic distribution pattern. Vernonia species serve as important nectar sources for butterflies and bees in tropical ecosystems.