Allium cernuum

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Monocots
Ordo: Asparagales

Familia: Amaryllidaceae
Subfamilia: Allioideae
Tribus: Allieae
Genus: Allium
Subgenus: A. subg. Amerallium
Sectio: A. sect. Lophioprason
Subsectio: A. subsect. Cernua
Species: Allium cernuum
Name

Allium cernuum Roth, Arch. Bot. (Leipzig) 1(2): 40. 1798.
Synonyms

Homotypic

Calliprena cernua (Roth) Salisb., Gen. Pl.: 89. 1866.
Cepa cernua (Roth) Moench, Suppl. Meth.: 80. 1802.
Gynodon cernuum (Roth) Raf., Fl. Tellur. 2: 18. 1837.

Heterotypic

Allium alatum Schreb. ex Roth, Arch. Bot. (Leipzig) 1(3): 40. 1798.
Allium allegheniense Small, Fl. S.E. U.S. 1: 263. 1903.
Allium cernuum f. alba J.K.Henry, Ottawa Naturalist 31: 56. 1917.
Allium cernuum f. obtusum Cockerell, Bull. Torrey Bot. Club 18: 173. 1891.
Allium cernuum subsp. neomexicanum (Rydb.) Traub & Ownbey, Pl. Life 23: 110. 1967.
Allium cernuum subsp. obtusum (Cockerell) Traub & Ownbey, Pl. Life 23: 110. 1967.
Allium cernuum var. neomexicanum (Rydb.) J.F.Macbr., Contr. Gray Herb. 56: 5. 1918.
Allium cernuum var. obtusum (Cockerell) Cockerell, Contr. W. Bot. 10: 8. 1902.
Allium neomexicanum Rydb., Bull. Torrey Bot. Club 26: 541. 1899.
Allium nutans Schult. & Schult.f. in J.J.Roemer & J.A.Schultes, Syst. Veg. 7: 1088. 1830), nom. illeg.
Allium oxyphilum Wherry, J. Wash. Acad. Sci. 15: 370. 1925.
Allium recurvatum Rydb., Mem. New York Bot. Gard. 1: 94. 1900.
Allium tricorne Poir. in J.B.A.M.de Lamarck, Encycl., Suppl. 1: 270. 1810.
Gynodon elliotii Raf., Fl. Tellur. 2: 18. 1837.

Distribution
Native distribution areas:
References

Roth, A.W., Arch. Bot. (Leipzig) 1(2): 40 1798.
Govaerts, R. et al. 2018. Allium cernuum in World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2018 Jul. 20. Reference page.
USDA, NRCS. 2006. The PLANTS Database, 6 March 2006 (http://plants.usda.gov). Data compiled from various sources by Mark W. Skinner. National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Vernacular names
English: Nodding onion, Lady's leek
svenska: Prärielök

Allium cernuum, known as nodding onion or lady's leek,[3] is a perennial plant in the genus Allium. It grows in dry woods, rock outcroppings, and prairies. It has been reported from much of the United States, Canada and Mexico including in the Appalachian Mountains from Alabama to New York State, the Great Lakes Region, the Ohio and Tennessee River Valleys, the Ozarks of Arkansas and Missouri, and the Rocky and Cascade Mountains of the West, from Mexico to Washington. It has not been reported from California, Nevada, Florida, Louisiana, Mississippi, New Jersey, Delaware, New England, or much of the Great Plains. In Canada, it grows from Ontario to British Columbia.[4][5][6][7][8]

Description

Allium cernuum is a herbaceous perennial growing from an unsheathed elongated conical bulb which gradually tapers directly into several keeled (thin and flat) grass-like leaves (2–4 mm, 3⁄32–5⁄32 in wide). Each mature bulb bears a single flowering stem, which terminates in a downward nodding umbel of white or rose, campanulate (bell-shaped) flowers that bloom in July and August. The flowers are arranged into downward facing umbels and each flower is about 5 mm (3⁄16 in) across, pink or white with yellow pollen and yellow anthers. A. cernuum does not have bulblets in the inflorescence.[9] The flowers mature into spherical crested fruits which later split open to reveal the dark shiny seeds.[4][10][11][12][13][14][15]
Habitat

Allium cernuum can be found growing in deciduous woodlands, to open grasslands.[9]

The species has a wide geographical distribution but is absent from much of its range. In the southern part of its range in North America it is limited to mountainous habitats, and in other parts of its North American range it is limited to local and disjunct population. It is absent from North Dakota and most of the great plains states and intermountain region of the US.[9] In Minnesota it is listed as a threatened species.[16]
Uses

Allium cernuum is edible and has a strong onion flavor, and has often been used in cooking.[17] It is grown in gardens for its distinctive nodding flowers that are white, pink, or maroon; it is winter hardy in USDA zones 3–9.[3]

Seed head

Illustration from Britton and Brown 1913

Inflorescence

Similar species

In addition to other species of Allium, wild garlic, field garlic, and wild leek look similar.[18] Any onion-like plant which lacks the expected odor should be suspect of being a similar-looking poisonous species, namely deathcamas.[18]
References

"Allium cernuum". Tropicos. Missouri Botanical Garden.
"Allium cernuum". World Checklist of Selected Plant Families (WCSP). Royal Botanic Gardens, Kew – via The Plant List.
Geoffrey Burnie (1999). Botanica: The Illustrated A-Z of Over 10,000 Garden Plants. Welcome Rain. p. 75. ISBN 0760716420.
McNeal Jr., Dale W.; Jacobsen, T. D. (2002). "Allium cernuum". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 26. New York and Oxford – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
"Allium cernuum". County-level distribution map from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014.
USDA, NRCS (n.d.). "Allium cernuum". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team.
Brako, L.; Rossman, A.Y.; Farr, D.F. (1995). Scientific and Common Names of 7,000 Vascular Plants in the United States. pp. 1–294.
CONABIO. 2009. Catálogo taxonómico de especies de México. 1. In Capital Nat. México. CONABIO, Mexico City.
Barbara Coffin; Lee Pfannmuller (1988). Minnesota's Endangered Flora and Fauna. U of Minnesota Press. p. 47. ISBN 978-0-8166-1689-3.
Hilty, John (2016). "Nodding Onion (Allium cernuum)". Illinois Wildflowers.
Gleason, H. A.; Cronquist, A.J. (1991). Manual of the Vascular Plants of Northeastern United States and Adjacent Canada (2 ed.). Bronx: New York Botanical Garden. pp. i–910.
Cronquist, A.J.; Holmgren, A. H.; Holmgren, N. H.; Reveal, J. L. (1977). "Vascular Plants of the Intermountain West, U.S.A.". In Cronquist, A.J.; Holmgren, A. H.; Holmgren, N. H.; Reveal, J. L.; Holmgren, P. K. (eds.). Intermountain Flora. Vol. 6. New York: Hafner Pub. Co. pp. 1–584.
Hitchcock, C. H.; Cronquist, A.J.; Ownbey, F. M.; Thompson, J. W. (1969). "Vascular Cryptogams, Gymnosperms, and Monocotyledons". In Hitchcock, C. L. (ed.). Vascular Plants of the Pacific Northwest. Vol. 1. Seattle: University of Washington Press. pp. 1–914.
Radford, A. E.; Ahles, H. E.; Bell, C. R. (1968). Manual of the Vascular Flora of the Carolinas. Chapel Hill: University of North Carolina Press. pp. i–lxi, 1–1183.
Moss, E. H. (1983). Flora of Alberta (2 ed.). Toronto: University of Toronto Press. pp. i–xii, 1–687.
"Endangered, Threatened, and Special Concern. Species ID Guide" (PDF). Minnesota Landscape Arboretum.
Bailey, L.H.; Bailey, E.Z. (1976). Hortus Third. New York: MacMillan. pp. i–xiv, 1–1290.
Elias, Thomas S.; Dykeman, Peter A. (2009) [1982]. Edible Wild Plants: A North American Field Guide to Over 200 Natural Foods. New York: Sterling. p. 58. ISBN 978-1-4027-6715-9. OCLC 244766414.