Annual herb 10 cm - 0.6 m tall Stem: elongate, hairy, slightly sticky. Leaves: opposite, numerous, 2 - 8 cm long, 1 - 3 mm wide, linear with a pointed tip, more or less parallel-veined, and hairy. Inflorescence: a long-stalked, dense spike of many flowers, head-like, 0.5 - 1.5 cm long, about 1 cm wide, hairy, subtended by hairy bracts. Stalk of each inflorescence axillary and 2 - 8 cm long. Flowers: stalkless or nearly stalkless, whitish, subtended by hairy bracts. Stamens four, exserted, alternate with corolla lobes. Style one. Sepals: four, green, elliptic to reverse egg-shaped with a blunt apex. Fruit: a dehiscent capsule (circumscissile). Seeds one or two, shiny brown, 2 - 3 mm long. Corolla: four-lobed, whitish, scarious (dry, thin, membranous). Lobes becoming reflexed, 1.5 - 2 mm long.
Similar species: This is the only Plantago in the Chicago Region with stem leaves. The leaves of the others are all basal.
Flowering: late July to early October
Habitat and ecology: Introduced from Eurasia. Occurs in waste ground and along railroads.
Occurence in the Chicago region: non-native
Etymology: Plantago comes from the Latin word planta, meaning footprint. Arenaria means "growing in sandy areas."
Short-lived, mostly annual, 1-6 dm, evidently hirsute and tending to be a little viscid; lvs numerous, cauline, opposite, linear or nearly so, entire, 2-8 cm נ1-3 mm; peduncles axillary, 2-8 cm; spikes 0.5-1.5 cm, dense, nearly 1 cm thick; bracts broad, rounded, conspicuously scarious-margined; the lowermost abruptly and firmly foliaceous-caudate; cor-lobes 1.5-2 mm, soon reflexed; seeds 1 or 2, brown, 2-3 mm; 2n=12. A weed in waste places, especially along railroad tracks; native to the e. Mediterranean region, now well established in e. U.S. (P. indica; P. arenaria) The name has often been misapplied to a related sp. without caudate tips on the bracts.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.