Borer

A borer is an organism or device that bores into solid materials. In biology, wood-borers are typically the larvae of insects such as beetles or moths that tunnel through wood or plant stems, forming galleries that can weaken living trees, lumber, or wooden structures. Boring activity often leaves signs such as exit holes, fine frass (wood dust), frayed or damaged sapwood, and internal tunnels that can compromise structural integrity. In industrial settings, a borer also refers to a drill or drilling tool used to create holes in wood, metal, or other materials.

Biological borers most commonly affect trees and processed wood. Beetle borers (including cerambycids and buprestids) lay eggs on bark or exposed wood; larvae bore inward, sometimes feeding for months or years before emerging as adults. Powderpost beetles, furniture beetles, and certain moth larvae infest finished woods and antique furniture, while some species target living trees, potentially contributing to decline or death if infestations are heavy. Notable examples of invasive or economically important borers include the emerald ash borer (Agrilus planipennis), which has caused extensive ash tree mortality in parts of North America, and the Asian longhorned beetle (Anoplophora glabripennis), which has a broad host range and has prompted quarantine and removal programs.

Management focuses on prevention, monitoring, and rapid response. This includes maintaining tree health, inspecting and removing infested wood, quarantines to limit spread, and, where appropriate, chemical or biological controls. In structural contexts, treatment may involve removing infested material or industrial-grade fumigation or heat treatments.

Drilling tools called borers include auger bits, brad-point bits, Forstner bits, and other bits designed to bore precise holes, often powered by hand or electric drills.