Press enter to begin your search

Keeping Warm This Winter Could Be Costly

How choosing the right firewood can save forests


It’s finally starting to feel like winter in San Diego! With colder mornings and some decent rainfall, there are some things you should keep in mind before warming up next to the fireplace. Firewood usually comes housing bugs and beetles. If these pests come from a different area, they can be detrimental to trees in a new area. This is why it’s so important to only burn wood you know is uninfested and was cut in your immediate area! Recently, we had to deal with a beetle infestation in some of our trees. The Kuroshio Shot Hole Borer (KSHB) has recently destroyed over 100,000 trees in the Tijuana River Valley and that same beetle was discovered on our Preserve in Olivenhain last fall.


The Shot Hole Borer can survive in many tree species, including oaks and sycamores. Dr. Akif Eskalen (UC Davis) and Shannon Lynch (UC Santa Cruz) are the researchers who helped identify the infestation and are leading the way in KSHB research. Under guidance from the researchers, we monitored the infested area for almost a year before the infestation started increasing in size. Before it could spread to other trees, we decided to take action. Following the researchers’ guidelines, two shot-hole-borer-infested Sycamores were cut to the ground. The wood was chipped into pieces smaller than 1” before transport for disposal. If pieces aren’t chipped to 1” or smaller, the beetle can still survive in the wood and continue to spread. The removal was particularly challenging because the 30’ trees were hanging over a concrete pipe belonging to Olivenhain Municipal Water District, and we really didn’t want to burst it!

What can you do to help?

The KSOB is native to Vietnam, and therefore our trees do not have defense mechanisms built up to withstand the infestation. This is why it’s so important to ask about the origin of your firewood. Transporting firewood can also transport this beetle into otherwise uninfested areas. The easiest way to help stop the spread is to burn it where you buy it!

If you think you might have a KSOB infestation you can read more about identifying marks below.

Another pest spotted in the Escondido Creek watershed is the Gold Spotted Oak Borer. While there haven’t been any GSOB sightings on our Preserves, it has been confirmed on Del Dios Preserve and Daley Ranch and are currently being monitored and treated.

More information can be found here: