1. Myagrum perfoliatum L. (S-Eur., SW-As.) – A rather rare and much decreasing, always ephemeral alien. First recorded in 1821 in Leuven (without further details). Observed as a wool alien in the Vesdre valley between 1891 and 1907 (possibly persisting for some time on a talus slope). Furthermore recorded on various occasions and in widely scattered locations but much rarer since 1950: on waste land near a steel plant in 1954 in Hoboken, on a railway bank in Vilvoorde, also in 1954 and on a dry pond margin in Nismes in 1956. In the past decades observed several times as a grain alien: in a roadverge in Pittem in 1994 (Verloove & Vandenberghe 1995) and under a grain conveyor at the Kattendijkdok in the port of Antwerpen in 1998. Since 2011 Myagrum perfoliatum was also regularly seen with several individuals in the port-area of Gent. Finally, in 2015 also recorded near a small grain mill in Moen.
Myagrum perfoliatum is usually found on waste land but there are several old records from agricultural fields as well (beets, etc.).
 |
 |
 |
References
Barnard I. (2006) Exotic plant introduction in Kansas, two new species. Sida, Contrib. Bot. 22(1): 777-779. [available online at: http://www.andestoamazon.com/Sida/PDF/PDF22%281%29/48_Barnard_KansasExotics_777-779.pdf]
Grenfell A.L. (1987) Adventive News 37.Myagrumperfoliatum L. in Cambridgeshire. BSBI News 47: 34-35.
Naithani H.B., Dayal R. & Bennet S.S.R. (1978) Occurrence of the genus Myagrum Linn.(Cruciferae) in Northern India. Indian Forester 104(3): 171-173.
Sutorý K. (1982) Rozšíření druhů Euclidium syriacum (L.) R. Br. a Myagrum perfoliatum L. v Československu. Čas. Morav.Muz. - VědyPřír., Brno 67: 119-123.
Verloove F. & Vandenberghe C. (1995) Nieuwe en interessante voederadventieven voor de Belgische en Noordfranse flora, hoofdzakelijk in 1994. Dumortiera 61-62: 23-45.