Convovulus sepium L.

Calystegia sepium plant

Family - Convolvulaceae

Stems - Twining, herbaceous, glabrous to hairy, from rhizomes, angled or terete.

Calystegia sepium stemStem at a node.

Leaves - Alternate, petiolate. Blades to 10cm broad at base, to +10cm long, ovate to lanceolate, entire, acute to acuminate, glabrous to pubescent, cordate to sagittate at base with auricles either squarish or rounded.

Inflorescence - Single axillary pedunculate flowers. Peduncles to +10cm long, glabrous to puberulent.

Flowers - Corolla to +/-5cm long, funnelform, white, glabrous or sparse puberulent externally. Stamens 5, adnate at base of corolla tube, erect. Filaments to +2.5cm long, with glandular pubescence at base, whitish. Anthers to 5mm long. Ovary ovoid, glabrous, green, 2-locular. Style to 2cm long, glabrous, whitish. Stigmas 2, slightly compressed. Sepals 5, lance-ovate, to 1.5mm long, 5mm broad, acute to blunt at apex, mucronate and with small cilia at apex. Calyx surrounded by two large green bracts. Bracts to 2cm long, -2cm broad, broadly ovate, glabrous.

Calystegia sepium flowerBracts covering the calyx.

Calystegia sepium flowerPinkish flower.

Flowering - May - September.

Habitat - Disturbed sites, waste ground, thickets, moist ground, roadsides, railroads.

Origin - Native to U.S.

Other info. - This species is synonymous with Calystegia sepium R. Br., which is the more excepted name now. "Calystegia" meaning "covered calyx".
This species, and indeed many species from this family, are seen as weedy or intrusive. "Convolvulus" meaning "to entwine", which is exactly how the plants grow, entwining themselves on any sturdy support.
Steyermark breaks the species down into three varieties, one of these varieties having three forms. The varieties are distinguished mainly on leaf size, shape, hairiness, and basal extension shape. One plant, C. sepium var. sepium f. coloratus Lange, has a rose colored corolla.
I will not break down the other varieties and forms here.

Photographs taken at Shawnee Creek, Shannon County, MO., 9-28-03 and at Logan Creek, Ellington, MO., 8-1-04.