Sp. Pl. ed. 2, 1: 423. 1762.
Bulbs 1–50+, ovoid, 0.2–1.5 × 0.2–1 cm; outer coats surrounding numerous, very dark purple bulbels, usually white or greenish, membranous, sometimes breaking into ± parallel, fibrous strips; inner coats white, cells obscure, quadrate. Leaves persistent, 2–5, sheathing 1/3–1/2 scape; blade solid, flat or channeled, carinate, 15–40 cm × 2–5 (–7) mm, margins entire. Scape persistent, solitary, erect, ± solid, 25–90 cm × 1–4 mm. Umbel persistent, erect, very dense, 80–200-flowered, globose, bulbils unknown; spathe bracts caducous, 2, 7–12-veined, lanceolate, ± equal, apex narrowed to beak, beak to 2 cm. Flowers campanulate, 4–7 mm; tepals erect, purple, or inner with broad whitish margins and purple midvein, oblong to ovate, ± equal, becoming keeled and ± rigid in fruit, margins entire, apex acute to obtuse; stamens included; filaments: outer unlobed, inner with 2 prominent teeth on either side of anther, teeth 2–3 times anther-bearing portion, usually papillose to ciliate; anthers yellow or purple; pollen light yellow to white; ovary crestless; style linear, ± equaling anther-bearing portion of stamens; stigma capitate, unlobed; pedicels 5–30 mm, outer much shorter than inner. Seed-coat dull; cells each with central papilla.
Phenology: Flowering May–Jul.
Habitat: Disturbed fields and roadsides
Introduced; Mich., c, s Europe
Allium rotundum is native to central and southern Europe. It is reported as established in southern Michigan, and is to be expected elsewhere in the Great Lakes region.
"thicker" is not a number."broad" is not a number.