Conringia orientalis (L.) Dum. (C and E Eur., SW As.) – A rare and much decreasing alien, known at least since ca. 1835 (probably longer). In the 19th century perhaps more or less established for some time as arable weed, especially in parts of Wallonia (for instance near Han-sur-Lesse). Also regularly found adventive in fields of alfalfa and clover. Furthermore recorded on waste land, dumps, near mills, etc.; more rarely also as wool alien in the valley of river Vesdre. In the past decades only exceptionally recorded. Observed, for instance, in a garden in Oud-Turnhout in 1984 and 1985 and near a grain-mill in the port of Roeselare in 1995 and 1996 (Verloove & Vandenberghe 1996).
Species of Conringia are often superficially similar to one another and their identity should be carefully checked. An old claim for Conringia orientalis from Wilsele (1893) turned out to belong to C. austriaca.
Rollins R.C. & Al-Shehbaz I.A. (1986) Weeds of south-west Asia in North America with special reference to the Cruciferae. Proc. Roy. Soc. Edinburgh B 89: 289-299.
Verloove F. & Vandenberghe C. (1996) Nieuwe en interessante voederadventieven voor de Belgische flora, hoofdzakelijk in 1995. Dumortiera 66: 11-32.