How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PEST

The branch and twig borer adult is a 0.3 to 0.6 inch (7–15 mm) long beetle, mostly black with brown wing covers. The C-shaped, white larvae are covered with fine hair. There is one generation per year.

DAMAGE

Adults bore small, round holes at the base of buds or axils of twigs injured by sunburn. Eggs are laid at these locations in early May and grubs bore into the heartwood, where they live for a year or more. Twigs break at location of the injury. Madrone, oak, and grape are the preferred hosts; olive damage may occur when trees are located next to these sources. Loss of a few small branches in an orchard is of little consequence to production.

MANAGEMENT

Prune out and burn infested wood. Prevent sunburn and other injury that predisposes trees to damage.

PUBLICATION

UC IPM Pest Management Guidelines: Olive
UC ANR Publication 3452
Insects and Mites
F. G. Zalom, Entomology, UC Davis
P. M. Vossen, UC Cooperative Extension, Sonoma County
R. A. Van Steenwyk, Insect Biology, UC Berkeley
M. W. Johnson, Kearney Agricultural Center, Parlier
Acknowledgment for contributions to Insects and Mites:
G. S. Sibbett, UC Cooperative Extension, Tulare County
L. Ferguson, Pomology, UC Davis

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