Attraction of different types of wood for adults of Morimus asper (Coleoptera, Cerambycidae)

Abstract

Morimus asper reproduces mainly in freshly dead wood and, as a consequence, populations are affected by modern forestry practices. The taxon M. funereus, now incorporated into the species M. asper, is protected by the Habitats Directive (Council Directive 92/43/EEC) and its monitoring has received attention in recent years. Larvae of M. asper are polyphagous, but some studies indicate that adults prefer the wood of some tree species. Freshly cut log piles, which attract adults, have been proposed as a monitoring tool. For monitoring programmes, it is essential to select the most appropriate wood and therefore the attraction of different types of wood for adults of M. asper was investigated in two sites in northern Italian, using freshly cut log piles. The first experiment was carried out in the Nature Reserve Bosco della Fontana (a lowland forest, Mantua province), testing two autochthonous species (Carpinus betulus and Fraxinus ornus) and two allochthonous species (Juglans nigra and Quercus rubra). The second study was conducted in the Parco Naturale Regionale delle Prealpi Giulie (a mountain area, Udine province), employing Fagus sylvatica, Fraxinus excelsior and Picea abies (all autochthonous species). The population of this area belongs to the taxon formerly named M. funereus. In both sites, adults clearly preferred the wood of some particular species: J. nigra at Bosco della Fontana and F. sylvatica in the mountain area. This is the first study which compared the attraction of several tree species and it showed that this selection is important for the monitoring of M. asper.