Prionus californicus - Ask Extension
We are in washing county between Hillsboro and Cornelious. We have been finding a beetle, Prionus californicus, or similar. Has there been an uptick...
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Prionus californicus #880396
Asked August 06, 2024, 1:04 PM EDT
We are in washing county between Hillsboro and Cornelious. We have been finding a beetle, Prionus californicus, or similar. Has there been an uptick in this root borer recently? We have had increasing instances of fruit trees with partial canopy die off in recent years. Could this be the reason? Thanks in advance for your response.
Washington County Oregon
Expert Response
Hello,
California prionus is a native beetle, therefore it has been present in our area for a long time. There is however, more focus on this insect, especially in orchards. I am not sure if there are actually more prionus present in orchards or if it has just been noticed as a pest more recently. Often when orchards are taken out they have been noticed in root systems. These orchards were often looking weakened and unhealthy prior to their removal, so it is possible that trees with canopy issues could have root systems infested with prionus.
Here is more information about the insect:
https://treefruit.wsu.edu/crop-protection/opm/california-prionus/
Thank you for using Ask Extension!
California prionus is a native beetle, therefore it has been present in our area for a long time. There is however, more focus on this insect, especially in orchards. I am not sure if there are actually more prionus present in orchards or if it has just been noticed as a pest more recently. Often when orchards are taken out they have been noticed in root systems. These orchards were often looking weakened and unhealthy prior to their removal, so it is possible that trees with canopy issues could have root systems infested with prionus.
Here is more information about the insect:
https://treefruit.wsu.edu/crop-protection/opm/california-prionus/
Thank you for using Ask Extension!
