Horntails, Wood Wasps

Family Siricidae

Tremex columba. Photo:Stephanie Boucher

Larvae are wood boring; most species attack conifers, but some are found in hardwood trees. These insects use their drill-like ovipositor to insert their eggs and spores of a symbiotic fungus into dead or dying trees. North American species only attack trees that have been weakened or recently cut down. The boring activities of the larvae reduces the quality of the lumber from these trees. Horntails are large, brightly coloured sawflies. Both sexes have a long abdomen with a horny spearlike plate on the last segment. Females have a long ovipositor.