Can California’s Redwoods Be Saved by Moving Them Out of State?
California has some impressive distinctions when it comes to trees: The state is home to the largest, tallest and oldest trees in the world.
But some scientists are worried that the narrow range of conditions in which these trees thrive may be threatened by the effects of climate change. Take the giant sequoia, for example, which is found today only in scattered groves on the southwestern side of the Sierra Nevada.
Sequoias are facing a lengthening dry season because the snowpack that keeps their soil moist is melting earlier in the year. And in the span of just 15 months in 2020 and 2021, horrific wildfires in California killed as much as 19 percent of the world’s sequoias.
“It’s highly likely that many of the giant sequoias in their current groves may not make it for the next century,” Park Williams, a climate scientist at U.C.L.A., told The New York Times. He added, “We’re already pushing up against the boundaries of what these trees can tolerate.”
Moises Velasquez-Manoff, a journalist based in the Bay Area, recently wrote in The New York Times Magazine about a possible solution to this problem: planting the trees outside their current ranges, in areas that are now more hospitable — a process called assisted migration. The idea is to save threatened plant and animal species by helping them to take root in safer places that they might not have been able to reach on their own; Moises followed one group that is planting redwoods in the Pacific Northwest.
You can read his fascinating article here.
I spoke to Moises about what he learned in his reporting. Here’s our conversation, which has been lightly edited for clarity.
Are California’s redwoods and sequoias unusual in how limited their habitats are? Or are all plants and animals able to survive only in places where the climate is just right for them?
It’s not unusual for species to occur in very limited geographic areas. Some species are more generalist or “cosmopolitan” than others, and exist across a variety of habitats — the coyote, say, which has colonized New York City and San Francisco and a large swath of land in between — but many others can thrive only in a very narrow set of conditions. All that said, California has some unique environments that might give rise to species that are confined to very small geographic areas in the state.
Is that true because of how vast the state is?
California has numerous and very different microclimates, for instance, such as the damp coastal “marine zone” in which coast redwoods thrive. This region is characterized by moisture from the sea — even though the state doesn’t get much rainfall for two-thirds of the year — and relatively cool temperatures. And then as soon as you cross the hills and enter the Central Valley, temperatures increase dramatically — a totally different ecozone.
The other important thing to understand about lowland California is that, in contrast with the East Coast, it was never covered by glaciers. What that means is that ice sheets have not repeatedly erased ecosystems here, as they have in, for example, New York. More time in a place arguably allows plants and animals to specialize in ways that animals on the East Coast have not, leading to more speciation.
Thus, you have not only coast redwoods and giant sequoia — trees adapted to very specific microclimates — but also the Monterey cedar and Monterey pine, two trees that are native to just a few spits of land along the Central Coast. It’s thought that both trees had more extensive forests during glaciation, meaning they retreated to their current cool coastal refuges — presumably the only places left where they could survive — when the world warmed.
Do you think some of the pushback against assisted migration is simply because it feels unnatural? As in, we’re messing with the natural order of things?
Scientists, I think, object more to the potential disasters that could occur. They’re well aware of how moving plants and animals around in the past has led to irreversible problems — invasive species forever altering the ecosystems they were introduced to. As one scientist told me, the road to hell is paved with good intentions.
But I do think that for some citizens, the worry is indeed that we’ve messed with nature so much that we shouldn’t be messing with it more. Basically, “Leave it alone already!” And there’s something to this argument.
One of the problems, though, is that what we think of as pristine nature in the U.S., particularly in California, is in fact a landscape that was shaped by Native Americans.
When John Muir and others were arguing for protecting nature in preserves in the late 19th century — a movement that led to some of the first national parks — the landscape they wanted to put off limits had in fact been shaped by Native Americans to produce the plants and animals they found useful. So, when people talk about leaving nature alone, it’s worth asking what their reference point is.
Did working on this article change how you think about responding to the effects of climate change?
It highlighted for me that in certain segments of the populace there is a deep desire to do something about this climate calamity that we’re all racing toward. These people don’t want to just sit there on the deck of the proverbial Titanic and listen to music as the whole thing sinks. This particular group of people, PropagationNation, has decided that planting the most massive — and tallest — tree species on the planet around Seattle is how it will scratch that “We’ve got to do something” itch.
And before you go, some good news
A new vaccine that protects birds against avian influenza is seeing promising early results in California’s endangered condors, giving wildlife officials new hope for the recovering bird species.
The vaccine, administered in a trial this past summer to condors at several West Coast zoos, was developed to protect the birds from a dangerous strain of avian flu that wiped out 21 free-flying condors in Arizona this year. Protecting the state’s fragile condor population from such threats is important, wildlife experts say; the wild birds nearly became extinct in California in the 1980s because of hunting, pesticides and lead poisoning.
Early results from the trial show that the new vaccine, which has so far been approved only in the U.S. for use in condors, elicits an antibody response in 60 percent of the birds that received a vaccine and represents an important step forward in continuing efforts to rehabilitate California’s condors.
Wildlife experts hope further results from the trial will prove similarity successful, paving the way for a vaccination program that could protect wild condors, too. “We’re all kind of waiting with bated breath to see what the final results are going to be,” Tiana Williams-Claussen, the director of the wildlife department for the Yurok Tribe in Northern California who has been involved in conservation efforts, told The Associated Press.