Panicum philadelphicum Bernh. ex Trin., Gram. Panic. [Trinius]: 216. 1826. = Panicum gattingeri Nash, Fl. S.E. U.S. [Small], 92 (1327). 1903. (Poaceae) Confirmation of naturalized neophyte for the flora of the province of Alessandria (Piemonte) (Soldano & Verloove, 2007). ITALY. Piemonte. Prov. Alessandria: Valenza, river Po S of the bridge, sandy river bank, few individuals, 07.09.2014, F. Verloove 10990 (BR). This North American species was only known from a single, historical record in Alessandria province (Soldano & Verloove, 2007). Its present-day presence is here confirmed. In Piemonte, it is also known from Torino province (Verloove & Selvaggi, 2011), also along river Po. Panicum philadelphicum is much reminiscent of P. capillare and both possibly have been confused in parts of Europe. It is readily distinguished by its panicles that are only ca. 1/3 the total height of the plant, the base of the peduncle that is not breaking at maturity and the slightly smaller spikelets that are acute at apex, not acuminate.

Published as part of Verloove, Filip & Ardenghi, Nicola M. G., 2015, New distributional records of non-native vascular plants in northern Italy, pp. 5-14 in Natural History Sciences 2 (1) on pages 9-10, DOI: 10.4081/nhs.2015.219, http://zenodo.org/record/12523705