Post-harvesting late summer-autumn weed vegetation in small size arable fields in Veneto: new insights into root crop communities in North East Italy

Abstract A research was conducted in the Veneto region (NE-Italy) inside kitchen gardens and potato fields of outer pre-Alps, and in asparagus fields on the low Po plain near the Adriatic coast, in late summer-autumn after harvesting. Original vegetation-plot records were compared with historic and recent materials from Italy, especially N-Italy, and with comparable associations from Central and South-Eastern Europe, to ensure a consistent syntaxonomical frame of this highly dynamic vegetation. At the same time it was possible to shed light on the actual occurrence of past coenoses, cited by Italian authors for the Po plain. The analysis not only confirmed the occurrence of Echinochloo-Setarietum pumilae in north-eastern Italian territories, but also showed that it was more extensive than previously thought. It also confirmed the persistence of Panico-Polygonetum persicariae. The historical presence of Veronico-Lamietum hybridi occurring in pre-Alps and Dolomites needs confirmation. Further regional-scale investigations of summer crop weed vegetation appear necessary.