Historic English oak tree (Quercus robur) and great capricorn beetle (Cerambyx cerdo): a difficult cohabitation. In this note we report the infestation by the great capricorn beetle (Cerambyx cerdo Linnaeus) (Coleoptera, Cerambycidae) of an old English oak tree (Quercus robur Linnaeus) that grows at Villanova S. Antonio in the municipality of Fossalta di Portogruaro (VE) (Veneto region, north-eastern Italy). The oak tree has a significant historical, cultural and landscaping value (it is a "National Monument"), while the cerambycid beetle is a protected species included in the Habitats Directive (Council Directive 92/43/EEC). The difficult relationship between the two species and the possible modes of intervention are discussed.