7. Ipomoea quamoclit L. (cypress vine)

Quamoclit vulgaris Choisy

Pl. 366 c, d; Map 1602

Plants annual. Stems 100–500 cm long, glabrous. Leaves mostly short-petiolate. Leaf blades 2–9 cm long, pinnately dissected into 9–19 pairs of lobes, appearing nearly pinnately compound, broadly ovate in outline, the lobes linear, sharply pointed at the tip, glabrous. Flowers solitary or in loose clusters of 2–5, glabrous. Sepals similar in size and shape or the outer 2 slightly shorter and narrower, 4–7 mm long, oblong-elliptic, rounded or narrowed to a bluntly pointed tip but with a minute, sharp point from just below the tip, glabrous. Corollas 2.2–3.5 cm long, trumpet-shaped, the tube slender, widened abruptly at the tip, scarlet red (rarely white elsewhere) with the throat usually yellow or white. Stamens exserted. Ovary 4-locular, the stigma 2-lobed. Fruits ovoid, the main body 7–10 mm long, the persistent style 5–9 mm long, glabrous. Seeds 4.5–5.5 mm long, the surface sparsely to moderately minutely hairy. 2n=30. June–October.

Introduced, uncommon and widely scattered (native of tropical America; widely but sporadically introduced in the eastern U.S.). Banks of streams; also fencerows, roadsides, railroads, and open, disturbed areas.

This species is cultivated for its large displays of brilliant scarlet flowers that attract hummingbirds. Once allowed to fruit, these self-fertile plants will tend to regrow from seed in future years. Fertile hybrids of intermediate morphology with I. coccinea have been developed horticulturally and are named I. Hmultifida (Raf.) Shinners, but these have not yet escaped from cultivation in Missouri.