5. Amaranthus caudatus L. (purple amaranth, love-lies-bleeding, tassel flower)

Pl. 198 e; Map 814

Plants monoecious. Stems 30–200 cm long, erect or ascending, glabrous or nearly so, unarmed. Leaves long-petiolate. Leaf blades 2–20 cm long, lanceolate to ovate or elliptic, narrowed or tapered to a bluntly or sharply pointed tip, narrowed or tapered at the base, the surfaces glabrous or the undersurface sparsely pubescent mostly along the veins with inconspicuous, mostly crinkled, multicellular hairs. Inflorescences usually red, less commonly mostly bright green, axillary and terminal, the axillary inflorescences short to long spikes, the terminal inflorescence usually a panicle with numerous clusters of short to long, dense spikes (these branching along mostly the lower half of the panicle axis), the flowers mostly continuous along the spikes, the tip curved or nodding, the main axis and branches sparsely to moderately pubescent with mostly crinkled, multicellular hairs. Bracts 1.7–2.5 mm long, shorter than to about as long as the fruits, lanceolate to ovate, narrowed or tapered to a sharply pointed tip, with a slightly thickened green midrib and broad, thin, papery margins, the midrib extending beyond the main body as a short awn, often somewhat spinelike at maturity. Staminate flowers with 5 more or less similar sepals, these 1.7–2.5 mm long, straight, oblong-elliptic to ovate, narrowed or tapered to a bluntly or more commonly sharply pointed tip, usually with a minute, awnlike extension of the midrib. Stamens 5. Pistillate flowers with 5 more or less similar sepals, these 1.5–2.0 mm long, noticeably overlapping, at least the outer ones outward-curved at the tip, oblong-obovate to spatulate, rounded to bluntly pointed, often with a minute, awnlike extension of the midrib. Stigmas 3, spreading. Fruits 1.6–2.5 mm long, with circumscissile dehiscence, the surface smooth or finely wrinkled above the midpoint when dry. Seeds 0.9–1.2 mm in diameter, angled along the rim, the surface pale whitish yellow, often reddish-tinged, especially along the rim, occasionally reddish brown. 2n=32, 34. July–October.

Introduced, uncommon and sporadic in Missouri (originated in South America, widely cultivated in tropical and warm-temperate regions, escaping sporadically in the U.S. and Canada). Gardens and open, disturbed areas.

Amaranthus caudatus is one of the cultigens derived long ago in the Andean region from selected strains of A. hybridus. It is one of the principal crop amaranths, but in the United States it is cultivated more commonly as an ornamental for its long, drooping, red inflorescences.