Rumex crispus L.
Family - Polygonaceae
Stems - Stems to -2m tall, simple or branching at the apex, erect, from a big taproot, herbaceous, glabrous, ribbed, becoming red with age.
Stem of mature plant.
Leaves - Basal leaves petiolate, to +/-50cm long (with petiole). Ocrea to -15cm long, scarious. Petiole to 20cm long, carinate. Blade lanceolate, crisped, glabrous, acute, +/-11cm broad, +/-45cm long, rounded at base, not cordate. Cauline leaves to +/-14cm long, glabrous, with smaller petiole than basal leaves, more crisped than basal leaves.
Leaf showing crisped margins.
Inflorescence - Terminal bracteate panicles to +/-40cm long (tall). Pedicels to 5mm long, with small swollen joint in basal 1/2.
Flowers - Outer perianth segments 3, 1.5mm long, green, glabrous, with scarious margins, rounded at apex. Inner perianth segments broadly ovate, to 2.5mm long in flower, glabrous, green. Ovary 3-sided, green, glabrous, 1mm long. Styles 3, reflexed, .6mm long. Stamens 6, adnate at base of perianth segments. Anthers yellow, to +1mm long. Filaments greenish, glabrous, 1mm long. Fruiting perianth segments becoming ferruginous, glabrous, to 5mm long, each with a tubercle. Tubercles to 1/2 the length of the fruiting perianth segments. Achenes ferruginous.
Plant with mature fruits.
Flowering - April - May.
Habitat - Fields, roadsides, railroads, waste ground, disturbed sites.
Origin - Native to Eurasia.
Other info. - This aggressive species is found throughout Missouri. The plant spreads easily can grow to quite a large size.
Photographs taken at the Kansas City Zoo, and off Mill St., Parkville, MO., 5-6-01, and in Van Buren, MO., 5-26-03.