Rhaponticum repens

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Scientific Name Rhaponticum repens (Acropiton repens) USDA PLANTS Symbol
Common Name Russian Knapweed, Hardheads ITIS Taxonomic Serial No.
Family Asteraceae (Sunflower) SEINet
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Description Life zones and habitat: Plains to foothills (3900 to 7500 ft). Disturbed areas, roadsides.
Plant: Colony-forming perennial with multiple leafy branches, 16 to 32 inches tall; foliage covered with fine hairs.
Leaves: Basal and lower stem leaves oblong, 1-3/4 to 6 inches long, often with toothed margins and deciduous by flowering; mid and upper leaves linear to linear-lanceolate or oblong, 3/8 to 2-3/4 inches long, with a sharp-pointed tip.
Inflorescence: Solitary flower heads atop each stem branch are urn-shaped, ~1/2 inch in diameter; silvery buds open to tubular flowers of pink or purple disk florets (no rays) with that turn straw-colored at maturity; protruding white anthers.
Bloom Period: June to September.
References: "Flora of Colorado" by Jennifer Ackerfield, Colorado Department of Agriculture and Invasive Species Compendium.
BONAP Distribution Map
Colorado Status:

© Tom Lebsack 2021