Pinellia ternata (Araceae) a silent inhabitant of Italian botanical gardens or something more?

Pinellia ternata is a small geophyte endemic to East-Asia, and well-known in traditional herbal Chinese medicine for its medicinal properties and recently, as an ornamental plant. For these reasons it was cultivated in the past in many Botanical Gardens around the world and because of its dispersal capability, in some regions it has become a casual (adventitious) or naturalized neophyte. In Europe, P. ternata was apparently first introduced and cultivated in 1829 near Ascoli Piceno (Italy) and later also in Botanical Gardens in Florence and Pavia. Subsequent data testify to its presence as a weed in Botanical Gardens in Austria (Graz, Klagenfurt, Salzburg) and Germany (Erlangen, Berlin, Görlitz, Kufstein). Since about the beginning of the 20th century, P. ternata has been reported as a naturalized alien species in anthropic and natural environments in the Franconia region of Austria and in Graz cemetery. Our recent findings attest, for the first time, to the presence of P. ternata in Piemonte (Italy). The species has recently been found growing in the Turin Botanical Garden, as a weed in some flowerbeds. Further research, based on seed catalogues, herbarium specimens, and an unpublished illustrated plate from Iconographia Taurinensis, has antedated the presence of this species in the Garden to before 1850; it was cultivated as a medicinal herb and then became a weed. Moreover, a newly-acquired specimen in the Herbarium of Turin (TO) collected at Lombriasco reports the first occurrence in the wild of this plant in Piemonte, and probably the first in Italy.