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Bugs - Bug Review - University of Illinois Extension

Peach Tree Borer

The Peach tree borer and the lesser peach tree borer attack the trunk and main limbs of stone fruit trees such as peach, cherry and plum and their related ornamental trees. The adults are clear-winged moths. The larvae are naked, grayish-yellowish white caterpillars with brown heads.

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Peach tree borer adult female

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Peach tree borer larva and pupa

Habit

These insects overwinter as larvae under the bark. When temperatures warm up in spring, they begin feeding on living inner bark. They continue to feed and grow and transform into a pupa from spring to late July. The adult moths soon emerge and the females of the peach tree borer lay eggs at ground level on the trunk of the tree, in cracks in the ground, or on bits of litter, while the females of the lesser peach tree borer lay eggs up and down the main limbs seeking rough bark or cracks. They are attracted to wounds where gum is exuding and where borers are present.

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Peach tree borer frass

Damage

The damage is caused by the feeding of the larvae on the growing inner bark. The wounds expand rapidly and limbs or trunks may be girdled. Open wounds permit entry of disease organisms that may also kill live tissue or decay the heartwood. Any wound on a stone fruit tree may cause gum to exude. Borer damage is usually attended by gumming with varying amounts of frass, or fecal pellets that look like sawdust. Larvae do not bore into the heartwood.

Control

Non chemical: Active wounds can be cleaned out or scraped with hand tools at any time to prevent further damage. All dead bark should be removed.

Chemical: Contact your county Extension office for current pesticide controls.