Insects That Attack Weakened or Damaged Trees and Freshly Cut Logs

Insects that attack and bore into living trees or freshly cut logs are generally referred to as wood borers. The greatest number of wood borers are in the insect orders Lepidoptera (moths) and Coleoptera (beetles). Solomon in Guide to Insect Borers in North American Broadleaf Trees and Shrubs describes some 300 species of wood borers.

Softwood species are most often used for log homes, and include pine, spruce, fir, hemlock, northern white cedar, western redcedar, and cypress. In warm weather, freshly cut logs of all softwoods are frequently attacked within a few days after tree felling by beetles commonly called buprestids and cerambycids. The larvae of buprestids and cerambycids are called flat-headed borers, and round-headed borers (Figure 31A, 31B, & 31C). These beetles do not infest logs that have been debarked; therefore, rapid utilization of felled logs is essential to prevent attacks from round and flat headed borers. Logs that are decked for several weeks often sustain heavy attacks from cerambycids and buprestids. Oftentimes these beetles will emerge from the logs after they have been erected in a house. Homeowners are often distressed initially when they see the beetles emerging from the logs in their house but they will not re-infest the logs and therefore no control is necessary.