Ovipositional behaviour and larval performance of Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) on cut branches of four North American tree species

Abstract

Abstract Velvet longhorned beetle Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) is native to Asia. It is reported to be polyphagous in its native range, but hosts have not been screened in its introduced range in the United States. We conducted choice and no‐choice host experiments. For choice assays, gravid T. campestris oviposited freely on cut branches of four tree species: Juglans nigra, Malus domestica, Acer saccharum, and Pinus strobus. We investigated oviposition between apple branches with and without cankers. Half of the choice trials underwent winter temperatures. For no‐choice assays, eggs were placed on cut branches of these same four species. Half of these branches were later dissected to measure larval development. The rest were exposed to winter temperatures and T. campestris emergence was quantified. Overall, Trichoferus campestris oviposition and development occur more readily on J. nigra and M. domestica than on A. saccharum or P. strobus. The insect oviposited more on cankered than uncankered apple wood. Cold exposure during an overwintering period benefitted insect development in adults. The insect's high degree of polyphagy and ability to reproduce in dry wood has likely facilitated its establishment in multiple locales around the world.