Invasive Shot Hole Borers
Invasive Shot Hole Borers
Invasive Shot Hole Borers
University of California
Invasive Shot Hole Borers

What are the Polyphagous and Kuroshio Shot Hole Borers?


The Polyphagous Shot Hole Borer (PSHB) is an invasive wood-boring beetle that attacks dozens of tree species in Southern California, including commercial avocado groves, common landscape trees, and native species in urban and wildland environments.

PSHB spreads a disease called Fusarium Dieback (FD), which is caused by pathogenic fungi. Trees that are FD-susceptible may experience branch dieback, canopy loss, and, in some cases, tree mortality.

Like PSHB, Kuroshio Shot Hole Borer (KSHB) is an exotic Euwallacea species that also vectors Fusarium Dieback. Both beetles are present in Southern California but are concentrated in different regions. See their known distribution here.


Keep Current

Insects, Disease Ravage Trees in Southland

The Los Angeles Times


Southern California Trees Threatened by Borer Beetles

California Audubon

Sandy DeSimone 6/6/17


Tree Will Need Replacing with More Resilient Species

NPR - Market Place

Aaron Schrank 6/7/17


Find out more by following this link:



PSHB in the News Again

Invasive shot hole borers are in the news again. Our collaborator, Greg McPherson with the US Forest Service, has just released a new estimate of the potential damage polyphagous and Kuroshio shot hole borers may cause as the spread across the...

Posted on Wednesday, April 19, 2017 at 1:33 PM




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Join the ISHB Email List was made possible by support from the US Forest Service Forest Health Protection Program, UC Riverside, Orange County Parks, the California Avocado Commission, and the work and in-kind support of federal, state, and local partners. 

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