Field Scabious - Knautia arvensis
Other Names:
Blue-button, Field Scabiosa
Taprooted perennial. Stems erect, branched above, 30–80 cm. Herbage hirsute. Basal leaves petiolate; blades oblanceolate, crenate, 3–15 cm long. Stem leaves oblanceolate, 4–20 cm long, deeply pinnately lobed; the lobes linear-lanceolate. Heads hemispheric, 1–3 cm across; involucral bracts lanceolate, 5–12 mm long; receptacle bracts absent. Flowers: calyx hirsute with 8 to 12 aristate sepals 2–4 mm long; corolla 4-lobed, light purple, glabrous to sparsely hairy, 6–8 mm long; lobes 1–3 mm long; stigma shallowly lobed; stamens barely exserted. Achene conical, 5–6 mm long, hirsute (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).