PEST PROFILES: BEETLES
Picture of Metallic Wood Borer adult
Metallic Wood Borer

Picture of flathead wood borer in the larva stage
Flatheaded Wood Borer

Picture of the Cottonwood Borer
Cottonwood Borer

Picture of the Longhorned wood borer larva
Longhorned Wood Borer

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Borer beetles

Description:
Round-headed beetles are elongate or oval with short antennae. Nearly all adults have some metallic coloration on their bodies. Larvae are elongate grubs with the segments just behind the head enlarged and flattened. They are usually white to cream colored with a darker plate on the thorax. The head is actually mostly hidden and fleshy. Flat-headed beetles have very long antennae, and adults are usually not metallic in coloration.

Damage:
Larvae of most species feed in trunks, branches or twigs of woody plants, usually when the plant is dying or dead. Larvae usually tunnel just under the bark surface but may go into the heartwood. Emergence holes of adults are most likely to have a semicircular shape or at least one relatively flat side. A few adults feed on leaves.

Life cycle: Adults emerge in the spring and summer depending upon the species. Eggs are oviposited in bark crevices and larvae develop inside the plant. Most species have 1 generation per year or take multiple years to develop. There are a few records of 8-year development. Pupation occurs within the plant.