Tremex fuscicornis

Tremex woodwasp Tremex fuscicornis is a wood wasp species found from Europe to Japan, belonging to the Siricidae family. This species targets a variety of broadleaf trees, including Fagus, Populus, Ulmus, Alnus, Quercus, Acer, and Prunus. It prefers Betula spp. The adult wasps typically mate in the upper branches of trees. Females select stressed or damaged trees for oviposition, laying 300-400 eggs. The eggs are deposited at an angle, spaced apart yet grouped within the wood. After hatching, the larvae initially feed on a symbiotic fungus's hyphae before creating longitudinal, semi-circular galleries up to 1 meter long. These galleries increase in diameter as the larvae grow. Pupation occurs at about 4 cm depth within the wood. The larvae take 1-3 years to develop fully, with adults typically emerging in late summer or fall.