Allium carinatum L. (C-Eur) – Formerly locally naturalized in Wallonia, primarily in the area around Verviers (Ensival, Lambermont, Hodimont). Known from there at least since 1811 but much decreasing in the 20th century and now probably extinct. The origin of these populations is unknown although they most likely refer to garden escapes. In 1957 also recorded near Namur and, more recently, in 2017 near Couvin. In the past years also recorded in Flanders, e.g. in 2016 in Kessel-Lo (Leopoldspark) but probably always as a mere relic of cultivation.
Selected literature:
Frost L.C., Houston L., Lovatt C.M. & Beckett A. (1991) Allium sphaerocephalon L. and introduced A. carinatum L., A. roseum L. and Nectaroscordum siculum (Ucria) Lindley on St Vincent's Rocks, Avon Gorge, Bristol. Watsonia 18(4): 381-385.
Konvicka O. (1972) Cytotaxonomische Studien von vier sterilen Arten der Gattung Allium. Biol. Pl. 14(1): 62-70.
Levan A. (1933) Cytological studies in Allium, III. Allium carinatum and Allium oleraceum. Hereditas 18(1-2): 101-114. [available online at: http://onlinelibrary.wiley.com/doi/10.1111/j.1601-5223.1933.tb02602.x/epdf]
Mennema J. (1982) Korte mededelingen. Gorteria 11(1): 22. [available online at: http://natuurtijdschriften.nl/search?identifier=536445;keyword=mennema]
Nilsson O. & Gustafsson L.-A. (1982) Projekt Linne rapporterar: 121-132 (Report from Project Linnaeus 121-132). Svensk Bot. Tidskr. 76(2): 135-145.
Oswald P. (1993) Native and naturalised Garlics in the Cambridge University Botanic Garden. Nat. Cambridgeshire 35: 67-75. [available online at: http://www.natureincambridgeshire.org.uk/volumes/nature-in-cambs-vol-35-...
Zeidler M. (1999) Genetic variability among populations of Allium carinatum subsp. carinatum. Thaiszia 9(1): 81-90. [available online at: https://www.upjs.sk/public/media/5738/thaiszia-9-081-090-1999-zeidler.pdf]