Peachtree borer on peaches and stone fruit
On peach, nectarine, cherry, plum and apricot the larvae feed under the bark from a few inches below the soil to about a foot above it, and the tree answers with a mass of gum full of frass. USDA-ARS trials in Georgia peach orchards found Steinernema carpocapsae gave over 80% control of existing larvae in spring and 77–100% fewer infestations when applied in autumn. The nematodes need moisture: the trials covered the treated base with soil or a water-retaining gel, and UC IPM advises warm but not hot weather, at least 60 °F.
At a glance
- Damage
- Gum mixed with frass and sawdust oozing from the trunk at the soil line
- Type
- Chewing
- Settings
- Garden, Field
- Threshold
- Any gum and frass at the trunk base
- Release
- Steinernema carpocapsae
- Rate
- 300,000 to 1 million infective juveniles per tree, applied to the trunk base (USDA trials); or 1 million or more per ounce of water squirted into each gallery (UC IPM)
How to confirm it
A jelly-like mass of gum mixed with brown frass and sawdust at the base of the trunk, from just below the soil to about a foot above it. Scrape it back and you find a cream-white larva with a brown head, up to 1½ inches long, in a tunnel under the bark. Gum and borers higher up the trunk or in the scaffold limbs point to the lesser peachtree borer instead.
Identification, lifecycle, degree days and every control option are on the full Peachtree borer profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Steinernema carpocapsae and stone fruit through so nothing is re-entered. Open the calculator →