Amaranthus hybridus
Amaranthus caudatus
green amaranth, green pigweed, hybrid amaranth, slender pigweed, slim amaranth, smooth amaranth, smooth pigweed
foxtail amaranth, love-lies-bleeding, purple amaranth, quilete
erect, green or sometimes reddish purple, rarely under-developed plants ascending, branched to nearly simple, 0.3–2(–2.5) m.
erect, usually green, moderately branched, rarely nearly simple, 0.5–1.5(–2.5) m.
petiole 1/2 as long as to equaling blade;
blade ovate, rhombic-ovate, or lanceolate, (2–)4–15 × (1–)2–6 cm, base cuneate to broadly cuneate, margins entire, apex acute to obtuse, with mucro.
petiole shorter than to equaling blade;
blade rhombic-ovate, ovate, or elliptic to broadly lanceolate, 5–15(–20) × 2–10 cm, base cuneate, margins entire, apex acute to subobtuse, with mucro.
lanceolate-linear to subulate, 2–3.5(–4) mm, subequal to or 2 times as long as tepals, apex spinescent.
narrowly lanceolate to linear, equaling or subequal to tepals, not exceeding style branches, apex acuminate with excurrent midrib.
terminal and axillary, erect or reflexed, occasionally nodding, green or olive green, occasionally with silvery or reddish purple tint, leafless at least distally, terrminal inflorescence often slightly nodding with numerous shorter branches at base.
terminal, drooping or nodding, usually red, purple, or white, less commonly green, silvery green, or yellow, usually much-branched at base, leafless at least distally, very large and robust.
at tips of inflorescences;
tepals 5;
stamens (4–)5.
mostly at tips of inflorescences;
tepals (4–)5;
stamens 5.
tepals 5, lanceolate to lanceolate-linear, subequal or unequal, 1.5–3 mm, membranaceous, apex acute or acuminate, gradually narrowing into aristate tip;
style branches erect, shorter than body of fruit;
stigmas 3.
tepals 5, spatulate-obovate or lanceolate-obovate, not clawed, subequal, (1–)1.5–2(–2.5) mm, membranaceous, apex obtuse, slightly emarginate, or subacute with mucro;
style branches spreading or reflexed;
stigmas 3.
black to dark reddish brown, lenticular to lenticular-globose, 1–1.3 mm, smooth, shiny.
dark brown to brownish black or reddish brown, yellowish white, or ivory, lenticular to subglobose, 1–1.2(–1.5) mm diam., smooth or indistinctly punctate.
obovoid or elongate-ovoid, 1.5–2.5 mm, shorter than tepals, smooth proximally, lid verrucose or rugose, dehiscence regularly circumscissile, or rarely in some presumably hybrid forms, irregularly dehiscent or indehiscent.
broadly ovoid to subglobose, 1.5–2(–2.5) mm, ± equaling tepals, dehiscence regularly circumscissile.
Amaranthus hybridus
Amaranthus caudatus
Originally a riverside pioneer in eastern North America, now Amaranthus hybridus is extremely abundant in agricultural fields and other disturbed habitats. Related cultivated species have been reported from the flora area, including A. caudatus, A. hypochondriacus, and A. cruentus; there is no evidence that they are established; specimens identified as these species are often variants of A. hybridus.
Distribution of Amaranthus hybridus in North America needs clarification because the name was misapplied to other species, notably A. powellii, and specimens of A. retroflexus, A. powellii, and A. hybridus are frequently interchangeably misidentified. Forms of A. hybridus and A. powellii with reddish inflorescences are often misidentified as escaped and hence presumably naturalized, cultivated species A. caudatus Linnaeus, A. hypochondriacus Linnaeus, and A. cruentus Linnaeus.
Amaranthus hybridus is extremely variable. In particular, there are numerous North American specimens with subobtuse tepals and thick inflorescences, suggesting hybridization with A. retroflexus. In Europe such presumably hybrid forms are known as A. ×ozanonii Thellung (A. Thellung 1914–1919).
A new, presumably hybridogenous taxon, Amaranthus ×tucsonensis Henrickson, was recently described from Arizona (J. Henrickson 1999). It was suggested that one of its parents is A. hybridus; the other parental species (probably a species with obtuse or spatulate tepals) remains unknown. The problem of proper taxonomic position and origin of A. ×tucsonensis needs further study.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
While reported as naturalized in some states, most specimens identified as Amaranthus caudatus are referable to A. hybridus or other native species. Amaranthus caudatus is one of the most popular domesticated amaranths and is cultivated primarily as an ornamental, and, to a lesser degree, as a pseudocereal. Plants of A. caudatus may occur locally, usually close to places of cultivation and mostly in the southern regions of the flora. No reliable records of their successful naturalization are available. It is impossible at present to trace records of such ephemeral populations and individual escapes; maps and detailed distribution statements for cultivated species of amaranths are not presented here.
The origin of Amaranthus caudatus remains uncertain. It is generally believed that it originated in South America or Central America from some unspecified wild race of the A. hybridus aggregate, probably South American A. quitensis Kunth. At least some cultivated forms and strains of A. caudatus probably developed with some degree of hybridization with other cultivated species. Numerous infraspecific entities that are mostly of horticultural importance have been described within A. caudatus. Forms with erect and robust club-shaped inflorescences have been recognized as A. mantegazzianus.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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- Local floras: CA, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, Go Botany, IL Wildflowers, KS Wildflowers, MI Flora, MO Plants, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
