Rhaponticum repens

FNA 2006, Kearney and Peebles 1969, Correll and Johnston 1970, Baldwin et al 2002, USDA GRIN

Duration: Perennial Nativity: Non-Native Lifeform: Forb/Herb General: Perennial herbs from slender, brown to black, creeping rhizomes; stems erect and openly branching, 30-100 cm tall, cobwebby-tomentose. Leaves: Alternate, entire, and glabrous to tomentose, the upper leaves oblong to linear-lanceolate, the lower ones pinnatifid, not much larger than the upper leaves, often deciduous by flowering. Flowers: Flower heads pinkish, discoid, arranged in flat-topped panicles; involucres urn-shaped, 1-2 cm high, the bracts (phyllaries) in 6-8 graduated series, with pointed, hyaline tips but not spine-tipped, the outermose phyllaries mostly glabrous and the inner cobwebby; florets all discs, 11-14 mm long, usually pink to lavender but can be white or blue. Fruits: Achenes ivory to grayish or brown, 2-4 mm long; topped with a pappus of white bristles, these 6-11 mm long, barbed below and short-plumose above. Ecology: Found in disturbed areas, fields, roadsides, ditches, and riverbanks, below 8,000 ft (2438) m; flowers in summer. Distribution: Native to Eurasia and naturalized in Australia and North and South America. In North America, ranges from British Columbia to Manitoba, south to Arkansas and Texas, west to California. Notes: The keys to this species are the pinnatifid lower leaves not much larger than the upper, entire leaves; the purple flowers; and the unarmed phyllaries with white hyaline (papery) tips. This introduced species is noted to be a serious pest, especially in cultivated fields as it is strongly allopathic and forms dense colonies. Ethnobotany: The bruised leaves were said to be used as a poultice for sores. FNA reports this species is poisonous, especially to horses. Etymology: Rhaponticum comes from the Greek rha for rhizomes; repens means creeping, or growing along the ground, referring to the rhizomatous growth form. Synonyms: Acroptilon repens, Centaurea repens, others, see Tropicos Editor: LCrumbacher 2011, AHazelton 2015, AHazelton 2017