What is this map?
This interactive map shows areas in California that may be more vulnerable to infestation by the Invasive shothole borers–Fusarium dieback (ISHB–FD) beetle-pathogen complex. It is designed as a decision-support tool to help prioritize monitoring and management activities.
Tutorial on how to use this map:
For help in understanding and using the ISHB Statewide Risk Map, view the video tutorial.
Key factors in understanding and using the map:
The map is based on a model by Lynch et al (2025) View the article explaining the model, which predicts risk of infestation by combining two key factors:
- Tree community composition (Host Related Risk): Areas with many trees that are closely related to known susceptible host species are at higher risk of infestation.
- Red areas indicate where local tree communities are predicted to be most vulnerable based on host-related susceptibility.
- Climate conditions (ISHB Generations): Warmer areas where the beetle can complete more reproductive cycles in a year are more favorable for its establishment and spread.
- Shading from light blue to yellow shows where climate conditions allow the beetle to reproduce more quickly in those locations, thus supporting more generations so that infestations may become more severe.
By overlaying these two factors, users can get a fuller picture of where the beetle is most likely to establish and spread.
Zoom in to see the potential risk in a specific area, or view in full screen mode.