I was listening to a scientist on NPR this morning talking about something that is not news: the trees in Southern California are dying. Well, it’s not news to me. As someone who has made a pretty serious hobby of hiking and biking the most forested parts of San Diego County I am sad to say that there really are no more "forested parts". Every year I climb Cuyamaca Peak to see how the ex-forest there is springing back to life. It is not.
I rolled my eyes at the title of this article, "The trees that make Southern California shady and green are dying. Fast." Southern California is not shady and it is not green. The trees that once did provide that service are dead. Now. And without that cooling and shade and stable ecosystem, are these detrimental conditions getting better, regressing to a mean? Or are they getting worse, caught in a feedback loop? From what I see in the back country, I believe it is the latter.
That article makes a lot of fuss about the shot hole borer beetle as a casual agent. If we could just get rid of this dang beetle! Perhaps if we did more to harass people about the fruit in their picnic lunch at the Arizona border we could catch all of these bugs and end the problem. But this misses the real problem. The real problem is that feedback loop and it involves global warming.
Shifting away from my opinion to something more scientific, I wondered what kind of falsifiable hypothesis could be made to demonstrate the real cause of California’s deforestation. I was thinking that damage from tree pests could be checked against weather patterns. Thankfully I don’t have to do the work myself because this specialist science person already did.
There is an apparent correlation between deficiency of rainfall and the abundance of this insect in destructive numbers. Heavy precipitation while the young broods are developing under the bark produces a very heavy and effective mortality.
If you cook the whole region, the trees die. Blaming the beetles for the tree deaths is like blaming bullets. If you had severe bullet problem would you think only about Kevlar body armor? That’s what we’re doing with the trees. What is the right answer? It’s hard to say. I have two ideas.
First, subsidize trees. Don’t make them the economic externality that people currently take for granted. Imagine two oligarchs dividing the earth’s surface in two equal halves and each owning one. (This is getting easier to imagine isn’t it?) One oligarch cuts down all the trees on his half. (Totally imaginable, right?) The question is, where is the breathable air in that half now coming from? In other words, people who are caring for trees are providing a valuable service and deserve to be compensated for it. If a place like San Diego doesn’t want to remain a desert wasteland they should give a property tax break related to the number of native trees. (No, invasive palm and eucalyptus do not count.)
The second solution strategy would be to follow the advice of geotechnical engineers. Since that is the profession of half of this blog’s readership I won’t presume to elaborate on the right answer, but here is the wrong answer: paving a huge area in such a way that when it does rain all the moisture in the entire region is immediately sent back to sea as fast as possible.
My grandmother was dismayed by San Diego’s tree depopulation in her lifetime (her father was the arborist for the city of Leicester). I’ve now been around long enough to see it myself. I personally don’t think Southern California is coming back. I think it will continue its transformation into a hostile desert wasteland which, like Phoenix and Las Vegas, millions of indoorsy people will be happy to exacerbate.
Like the Lorax I don’t just speak for the trees. I’m hoping to follow him too. Did you know that the Lorax was from San Diego? True. And once the trees were gone so was he. But I’m not just moving up the coast. The Bay Area, with its proximity to wonderful stands of redwoods, should carefully note the tragedy of San Diego County’s forests.