Taxon: Amaranthus retroflexus L.

Summary

Genus:

Amaranthus

Subgenus:

Amaranthus

Family:

Amaranthaceae

Nomen number:

2803

Place of publication:

Sp. pl. 2:991. 1753

Protologue link:

https://www.biodiversitylibrary.org/page/359012

Typification:

View in Linnean Typification Project

Verified:

02/04/2003 ARS Systematic Botanists.

Accessions:

34 (28 active, 27 available) in National Plant Germplasm System. (Map it)

Other conspecific taxa

Amaranthus retroflexus var. delilei (0 active accession[s])
Amaranthus retroflexus var. retroflexus (0 active accession[s])

Autonyms (not in current use), synonyms and invalid designations

Images (1 total. Click on image for more.)

Links

Forestry Images – from www.forestryimages.org
Seeds or fruits – Seed ID Workshop image, from Department of Horticulture and Crop Science, Ohio State University

Conservation Status

Reference(s)

University of Georgia Center for Invasive Species and Ecosystem Health
Aldén, B., S. Ryman, & M. Hjertson. 2012. Svensk Kulturväxtdatabas, SKUD (Swedish Cultivated and Utility Plants Database; online resource)
APHIS. Agricultural Risk Management System United States Department of Agriculture.
Botanical Society of the British Isles. BSBI taxon database (on-line resource).
Brown, R. G. & M. L. Brown. 1984. Herbaceous plants of Maryland
Browne, E. T. & R. Athey. 1992. Vascular plants of Kentucky: an annotated checklist
Chan, K. F. & M. Sun. 1997. Genetic diversity and relationships detected by isozyme and RAPD analysis of crop and wild species of Amaranthus. Theor. Appl. Genet. 95:865-873.
CIBA-GEIGY, Basel, Switzerland. 1968-1974. The CIBA-GEIGY Weed Tables 23.1.
Correll, D. S. & M. C. Johnston. 1970. Manual of the vascular plants of Texas
Costea, M. et al. 2004. The biology of Canadian weeds. 130. Amaranthus retroflexus L., A. powellii S. Watson and A. hybridus L. Canad. J. Pl. Sci. 84:631-668.
Darbyshire, S. J. 2003. Inventory of Canadian Agricultural Weeds Agriculture and Agri-Food Canada. 90.
Duncan, W. H. & J. T. Kartesz. 1981. Vascular flora of Georgia: an annotated checklist.
El-Hadidi, M. N. & M. S. Abdallah. 1980-. Flora of Egypt.
Erhardt, W. et al. 2008. Der große Zander: Enzyklopädie der Pflanzennamen 2:1197.
Feuillet, C. 1998. pers. comm. Note: re. French common names
FNA Editorial Committee. 1993-. Flora of North America.
Gleason, H. A. & A. Cronquist. 1991. Manual of vascular plants of northeastern United States and adjacent Canada, ed. 2
Groth, D. 2005. pers. comm. Note: re. Brazilian common names
Holm, L. et al. 1979. A geographical atlas of world weeds
Integrated Botanical Information System (IBIS). Australian plant common name database (on-line resource).
Kingsbury, J. M. 1964. Poisonous plants of the United States and Canada.
Liberty Hyde Bailey Hortorium. 1976. Hortus third. A concise dictionary of plants cultivated in the United States and Canada
Lira, R. et al., eds. 2016. Ethnobotany of Mexico Springer, New York, US. 114-115.
Magee, D. W. & H. E. Ahles. 1999. Flora of the Northeast. A manual of the vascular flora of New England and adjacent New York.
McGregor, R. L. et al. (The Great Plains Flora Association). 1986. Flora of the Great Plains.
Mitich, L. W. 1997. Redroot pigweed (Amaranthus retroflexus). Weed Technol. 11:199-202.
Munro, D. B. Canadian poisonous plants information system (on-line resource).
Ohwi, J. 1965. Flora of Japan (Engl. ed.).
Oseland, E. et al. 2020. Examination of commercially available bird feed for weed seed contaminants. Invasive Pl. Sci. Managm. 13:14-22. DOI: 10.1017/inp.2020.2. Note: the most common Amaranthus species in seed mixes
Porcher, M. H. et al. Searchable World Wide Web Multilingual Multiscript Plant Name Database (MMPND) (on-line resource).
Radford, A. E. et al. 1964. Manual of the vascular flora of the Carolinas.
Rehm, S. 1994. Multilingual dictionary of agronomic plants
Sauer, J. D. 1967. The grain amaranths and their relatives: a revised taxonomic and geographic survey. Ann. Missouri Bot. Gard. 54:107.
Tutin, T. G. et al., eds. 1993. Flora europaea, ed. 2.
Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
Whitson, T. D. et al., eds. 1999. Weeds of the West, ed. 5
Wofford, B. E. Database of Tennessee vascular plants (on-line resource).
Wu Zheng-yi & P. H. Raven et al., eds. 1994-. Flora of China (English edition).

Common names

Language	Name	Alternate name	note	seq	Citation
English	American pigweed			1	Integrated Botanical Information System (IBIS). Australian plant common name database (on-line resource).
English	carelessweed			1	Integrated Botanical Information System (IBIS). Australian plant common name database (on-line resource).
English	common amaranth			1	Botanical Society of the British Isles. BSBI taxon database (on-line resource).
English	pigweed redroot			1	Integrated Botanical Information System (IBIS). Australian plant common name database (on-line resource).
English	redroot			1	Wiersema, J. H. & B. León. 1999. World economic plants: a standard reference CRC Press, Boca Raton, FL.
English	redroot amaranth			1	FNA Editorial Committee. 1993-. Flora of North America.
English	redroot pigweed			1	Wiersema, J. H. & B. León. 1999. World economic plants: a standard reference CRC Press, Boca Raton, FL.
English	reflexed amaranth			1	Integrated Botanical Information System (IBIS). Australian plant common name database (on-line resource).
English	rough pigweed			1	Wiersema, J. H. & B. León. 1999. World economic plants: a standard reference CRC Press, Boca Raton, FL.
English	wild-beet amaranth			1	FNA Editorial Committee. 1993-. Flora of North America.
Chinese	fan zhi xian	反枝苋		2	Wu Zheng-yi & P. H. Raven et al., eds. 1994-. Flora of China (English edition).
English (Canada)	redroot pigweed		Agriculture & Agri-Food Canada official name	2	Darbyshire, S. J. 2003. Inventory of Canadian Agricultural Weeds Agriculture and Agri-Food Canada. 90.
French	amarante réfléchie			2	Feuillet, C. 1998. pers. comm. Note: re. French common names
French (Canada)	amarante à racine rouge		Agriculture & Agroalimentaire Canada nom officiel	2	Darbyshire, S. J. 2003. Inventory of Canadian Agricultural Weeds Agriculture and Agri-Food Canada. 90.
German	Ackerfuchsschwanz			2	Rehm, S. 1994. Multilingual dictionary of agronomic plants
German	zurückgekrümmter Fuchsschwanz			2	Erhardt, W. et al. 2008. Der große Zander: Enzyklopädie der Pflanzennamen 2:1197.
Portuguese (Brazil)	carurú-áspero			2	Groth, D. 2005. pers. comm. Note: re. Brazilian common names
Spanish	amaranto común			2	Rehm, S. 1994. Multilingual dictionary of agronomic plants
Spanish (Mexico)	quintonil			2	Lira, R. et al., eds. 2016. Ethnobotany of Mexico Springer, New York, US. 114-115.
Swedish	svinamarant			2	Aldén, B., S. Ryman, & M. Hjertson. 2012. Svensk Kulturväxtdatabas, SKUD (Swedish Cultivated and Utility Plants Database; online resource)

Distribution

order_code	Status	Continent	Subcontinent	Country	State	Note	Reference
1	Native	Northern America	Eastern Canada	Canada	New Brunswick		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Eastern Canada	Canada	Nova Scotia		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Eastern Canada	Canada	Ontario		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Eastern Canada	Canada	Prince Edward Island		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Eastern Canada	Canada	Québec		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Illinois		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Iowa		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Kansas		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Minnesota		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Missouri		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Nebraska		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	North Dakota		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Oklahoma		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	South Dakota		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	North-Central U.S.A.	United States	Wisconsin		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Connecticut		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Indiana		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Maine		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Massachusetts		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Michigan		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	New Hampshire		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	New Jersey		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	New York		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Ohio		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Pennsylvania		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Rhode Island		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	Vermont		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northeastern U.S.A.	United States	West Virginia		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northern Mexico	Mexico	Baja California (Norte)		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Baja California Sur		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Chihuahua		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Coahuila de Zaragoza		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Durango		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Nuevo León		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	San Luis Potosí		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Sinaloa		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Sonora		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northern Mexico	Mexico	Tamaulipas		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Northwestern U.S.A.	United States	Montana		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Northwestern U.S.A.	United States	Wyoming		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	South-Central U.S.A.	United States	New Mexico		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	South-Central U.S.A.	United States	Texas		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Alabama		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Arkansas		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Delaware		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	District of Columbia		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Florida	http://www.plantatlas.usf.edu/main.asp?plantID=1624	FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Georgia		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Kentucky		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Louisiana		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Maryland		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Mississippi		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	North Carolina		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	South Carolina		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Tennessee		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southeastern U.S.A.	United States	Virginia		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Southern Mexico	Mexico	Chiapas		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Colima		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Jalisco		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	México		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Morelos		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Nayarit		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Oaxaca		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Southern Mexico	Mexico	Veracruz de Ignacio de la Llave		Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.
1	Native	Northern America	Western Canada	Canada	Alberta		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Western Canada	Canada	Manitoba		FNA Editorial Committee. 1993-. Flora of North America.
1	Native	Northern America	Western Canada	Canada	Saskatchewan		FNA Editorial Committee. 1993-. Flora of North America.
4	Naturalized					natzd. nearly worldwide	Holm, L. et al. 1979. A geographical atlas of world weeds

Native
Northern America

EASTERN CANADA: Canada [New Brunswick, Nova Scotia, Ontario, Prince Edward Island, Québec]
WESTERN CANADA: Canada [Alberta, Manitoba, Saskatchewan]
NORTHEASTERN U.S.A.: United States [Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, Vermont, West Virginia]
NORTH-CENTRAL U.S.A.: United States [Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Wisconsin]
NORTHWESTERN U.S.A.: United States [Montana, Wyoming]
SOUTHEASTERN U.S.A.: United States [Alabama, Arkansas, Delaware, District of Columbia, Florida (http://www.plantatlas.usf.edu/main.asp?plantID=1624), Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Tennessee, Virginia]
SOUTH-CENTRAL U.S.A.: United States [New Mexico, Texas]
NORTHERN MEXICO: Mexico [Baja California (Norte), Baja California Sur, Chihuahua, Coahuila de Zaragoza, Durango, Nuevo León, San Luis Potosí, Sinaloa, Sonora, Tamaulipas]
SOUTHERN MEXICO: Mexico [Chiapas, Colima, Jalisco, México, Morelos, Nayarit, Oaxaca, Veracruz de Ignacio de la Llave]

Naturalized (natzd. nearly worldwide)

Reference(s)

FNA Editorial Committee. 1993-. Flora of North America.
Holm, L. et al. 1979. A geographical atlas of world weeds
Villaseñor, J. L. 2016. Checklist of the native vascular plants of Mexico. Rev. Mex. Biodivers. 87:559-902. DOI: 10.1016/j.mb.2016.06.017.

Economic Uses

Usage	Type	Note	Reference
Environmental	soil improver	potential	Costea, M. et al. 2004. The biology of Canadian weeds. 130. Amaranthus retroflexus L., A. powellii S. Watson and A. hybridus L. Canad. J. Pl. Sci. 84:631-668.
Human food	vegetable		Lira, R. et al., eds. 2016. Ethnobotany of Mexico Springer, New York, US. 114-115.
Vertebrate poisons	mammals		Kingsbury, J. M. 1964. Poisonous plants of the United States and Canada.
Weed	seed contaminant	of birdseed mixes	Oseland, E. et al. 2020. Examination of commercially available bird feed for weed seed contaminants. Invasive Pl. Sci. Managm. 13:14-22. DOI: 10.1017/inp.2020.2. Note: the most common Amaranthus species in seed mixes
Weed	seed contaminant	potential	CIBA-GEIGY, Basel, Switzerland. 1968-1974. The CIBA-GEIGY Weed Tables 23.1.

Cite as: USDA, Agricultural Research Service, National Plant Germplasm System. 2026. Germplasm Resources Information Network (GRIN Taxonomy). National Germplasm Resources Laboratory, Beltsville, Maryland.
URL: https://npgstest.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=2803. Accessed 14 April 2026.