Contain the Infestation

Many wood-boring pests, including ISHB, are spread by the transport of infested wood material. Researchers believe that the Goldspotted Oak Borer, which is contributing to the death of native oaks in Southern California, may have traveled from Arizona on infested firewood.

The transport of invasive insects is not intentional, but it can have severe consequences for agriculture and native and urban forests. There are two important ways that we can stop the spread of destructive pests like ISHB:

  1. Don't Move Firewood!
    Buy firewood where you intend to burn it. Visit for additional resources and information that you can share with others.

  2. Properly Dispose of Infested Material
    Beetles can emerge from infested material weeks after the branches or tree have been removed. If infested wood cannot be treated on-site, always cover wood chips and logs when transporting them to other facilities for treatment. The wood should also be tightly covered if it needs to be kept on-site for a short period.

    Do not use untreated, ISHB-infested logs or chips for firewood or mulch. Options for treating infested material include solarization, composting, kiln-drying, biogeneration, and use as alternative daily cover. Learn more about these options here.

Pruning Tips

Poor pruning practices can facilitate the spread of plant disease. So far, researchers have only observed Fusarium dieback spreading with the help of ISHB - but other species of Fusarium fungi have been known to travel on tools, equipment, and even through the soil.

Any pruning, sampling, or other tools that come into contact with infected wood should be sterilized before being used on uninfected trees. This includes chainsaws and wood chipping equipment. If several infested and uninfested trees need to be maintained on a property, we recommend managing the trees in batches: take care of all of the uninfested trees first, then move on to the infested trees, so that your tools won't need to be cleaned until the end of the day. 

For pruning and tool sterilization tips, see UC Riverside's "Best Management Practices for Disease in Oak Woodlands" (Lynch and Eskalen 2014).