Hosts: all fruit trees, but more common in cherry and peach
Biology: Prionus root borer (right) and ten-lined June beetle grubs feed on roots and crowns of cherry and peach. They can be a problem in sandy soils, and in new orchard sites.
Symptoms/Damage: General tree decline with few other above ground symptoms. Extensive feeding throughout roots and within crown wood.
Monitoring: Ground bucket traps baited with prionic acid pheromone lures will attract male prionus beetles.
Treatment Threshold: No threshold determined.
Degree Day Model: None
Management Considerations: Soil application of a systemic insecticide may be an effective treatment in young trees with small root systems. Check the insecticide label to be sure the fruit crop is listed before use.
Entomopathogenic nematodes and fungi can be effective on June beetle larvae.
Mass trapping with a pheromone lure can help to reduce prionus populations.