Locust borer

Definition

A species of longhorn beetle (Cerambycidae), Megacyllene robiniae, endemic to eastern North America and a specialist pest of black locust (Robinia pseudoacacia). Adults are active in late summer, feeding on goldenrod pollen, while larvae tunnel through the heartwood of living trees, often girdling stems and weakening structural integrity. The species is sympatric with its host and serves as a significant factor in black locust management and forest ecology.

Etymology

From 'locust' (the host tree, black locust, Robinia pseudoacacia) and 'borer' (referring to larval wood-boring habit).

Example

In eastern hardwood forests, locust borer larvae frequently infest young black locust stands, creating zigzag galleries that predispose trees to wind breakage; adult beetles can be recognized by their striking yellow and black banded elytra and long antennae.

Synonyms

• Megacyllene robiniae

Related Terms

• Cerambycidae
• longhorn beetle
• Robinia pseudoacacia
• wood-boring beetle
• host specificity
• sympatry
• heartwood
• girdling

Usage Notes

The common name refers specifically to the beetle's association with black locust, not to locusts (grasshoppers) in the orthopteran sense. The term 'locust' in this context is a historical misnomer for the tree, derived from the resemblance of Robinia pods to those of the carob tree (Ceratonia siliqua), known as 'locust' in biblical contexts. In entomological literature, 'locust borer' unambiguously designates Megacyllene robiniae; use the scientific name when discussing global cerambycid diversity to avoid confusion with unrelated borers.