Figure E.1.

Data on observed presences and absences of elm trees in Northern Italy. The information compiles different data sources as coloured. Neither of the data sources is deemed comprehensive regarding area coverage or observed absences. Additionally, the stem diameter of recognised tree presences is not equal across data sources and might comprise small trees not representing habitat for reproduction of the beetle (establishment). Symbols related to the Italian Forest Inventory represent the south‐west corners of 1 km × 1 km grid cells including (red circles) or not (grey crosses) Ulmus plants. Squares indicate centroids of polygons (Emilia Romagna, Lombardy, Piedmont) or grid cells (Tuscany) with records of the presence of Ulmus plants. Yellow triangles represent Ulmus plants inspected within the Tuscany phytosanitary monitoring program