California's Trees Are Dying, and Might Not Be Coming Back (phys.org) 77
An anonymous reader quotes a report from Phys.Org: [N]ew research from the University of California, Irvine reports that trees in California's mountain ranges and open spaces are dying from wildfires and other pressures -- and fewer new trees are filling the void. "The forests are not keeping up with these large fires," said study co-author James Randerson, the Ralph J. and Carol M. Cicerone Professor of Earth system science at UCI. Across the entire state, tree cover area has declined 6.7 percent since 1985. "These are big changes in less than four decades," he said. It's the first time that researchers have been able to measure tree population declines in California, and attribute the changes to such pressures as wildfires, drought stress and logging.
For the study, the UCI-led team used satellite data from the USGS and NASA's Landsat mission to study vegetation changes between 1985 and 2021. They found that one of the starkest declines in tree cover was in Southern California, where 14 percent of the tree population in local mountain ranges vanished, potentially permanently. The rate and scale of decline varies across the state. Tree cover in the Sierra Nevada, for instance, stayed relatively stable until around 2010, then began dropping precipitously. The 8.8 percent die-off in the Sierra coincided with a severe drought from 2012 to 2015, followed by some of the worst wildfires in the state's history, including the Creek Fire in 2020.
Fortunately "in the north, there's plenty of recovery after fire," said [Jonathan Wang, a postdoctoral researcher in Randerson's research group, who led the study published in AGU Advances], perhaps because of the region's higher rainfall and cooler temperatures. But even there, high fire years in 2018, 2020 and 2021 have taken a visible toll. The tree decline has also affected carbon storage abilities in the state, said Randerson, who added that the next step is to precisely quantify the impact on forests' ability to absorb anthropogenic carbon dioxide.
For the study, the UCI-led team used satellite data from the USGS and NASA's Landsat mission to study vegetation changes between 1985 and 2021. They found that one of the starkest declines in tree cover was in Southern California, where 14 percent of the tree population in local mountain ranges vanished, potentially permanently. The rate and scale of decline varies across the state. Tree cover in the Sierra Nevada, for instance, stayed relatively stable until around 2010, then began dropping precipitously. The 8.8 percent die-off in the Sierra coincided with a severe drought from 2012 to 2015, followed by some of the worst wildfires in the state's history, including the Creek Fire in 2020.
Fortunately "in the north, there's plenty of recovery after fire," said [Jonathan Wang, a postdoctoral researcher in Randerson's research group, who led the study published in AGU Advances], perhaps because of the region's higher rainfall and cooler temperatures. But even there, high fire years in 2018, 2020 and 2021 have taken a visible toll. The tree decline has also affected carbon storage abilities in the state, said Randerson, who added that the next step is to precisely quantify the impact on forests' ability to absorb anthropogenic carbon dioxide.
Fought fires too much, then? (Score:1, Interesting)
Forest fires are pretty natural. But if you fight tooth and nail to prevent them, to stop them from burning the excess, the biomass keeps heaping up. And then, when fire inevitably strikes anyway, it burns hotter, more fiercely, and longer than it otherwise would have done. Doing more damage.
So, if "fires" now do lasting damage, is that because we humans fought the fires too successfully?
Re:Fought fires too much, then? (Score:5, Insightful)
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When the bushes and such in the undergrowth are burned off before they get massive enough to also ignite the trees above they tend to die back, and the roots die off and rot in the soil. As they do so they shrink, and create tree-structured channels that trap water, and allow it to rapidly percolate into subsoils where they can provide water for deep soil water users, i.e. trees. Conversely, when the brush load is high, the temperatures achieved increase, and it tends to essentially bake the earth into hard
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Re: Fought fires too much, then? (Score:2)
And even that was mostly a cultural concession to appease the local Red Indian tribes.
Sometimes the information that "culture" conveys is correct.
Re:Fought fires too much, then? (Score:4, Interesting)
Another problem is the absence of apex predators, especially wolves. They were wiped out in California a century ago.
Since then, the mule deer population has soared. The deer eat the seedlings before they can grow into small trees. Without small trees to shade the ground, dry grass dominates and contributes to the spread of fires.
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Coyotes don't really serve the same function, though. I have coyotes that run down the middle of the street in my neighborhood in San Francisco. They're probably hunting squirrels, skunks, and more likely, feral cats. They're not doing anything to contribute to the environmental function of the mule deer that the GP describes.
Re: Fought fires too much, then? (Score:2)
What about mule deer hunting on the part of humans then? Or does gun control and PETA prevent that?
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Humans don't kill near enough deer to make a difference.
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Since then, the mule deer population has soared. The deer eat the seedlings before they can grow into small trees. Without small trees to shade the ground, dry grass dominates and contributes to the spread of fires.
And surely it's illegal to hunt in California.
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Since then, the mule deer population has soared. The deer eat the seedlings before they can grow into small trees. Without small trees to shade the ground, dry grass dominates and contributes to the spread of fires.
And surely it's illegal to hunt in California.
Even worse. The deer contain chemicals known to the State of California to cause cancer and reproductive harm.
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Prescribed firest can and do go out of control and with the utter lack of defensibility that makes them a hard sell.
Time to focus on defensibility and recognize 100 feet is not defensible. Home owners should be able to guard homes and that can't happen with a forest fire storm 100 feet away. 1 fire fighter for every home can deal with embers flying in from miles whereas 1 fire fight for a 100 homes can't, especially if they have to break in first. Manicured nature close to homes, then a fuck huge fuel break
Applying foam to homes ... (Score:3)
The idea was to have the homeowner apply when possibly threatened, leave for their safety, and come back a day or three later when the threat is over. Note that this would g
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Controlled burns do not compare to natural burns (Score:2)
Forestry management noticed what you are talking about a long time ago. They've been doing controlled burns for decades to get rid of that problem..
The controlled burns do not remotely compare to natural burns. A study that is part of the old data everyone refers to compared fires north and south of the US/Mexico border. Fires aggressively fought on US side, minimally fought on Mexican side. On the Mexican side we had a patchwork of smaller burns that acted as highly effective fire breaks. Controlled burns are typically much much smaller than natural burns and do not provide an equivalent fire break. We are not emulating nature, our fires are way too s
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What has been happening up here in BC is the springs have become hotter.
The snow melts quick, the warm weather and lots of snow melt triggers a lot of underbrush growth, it then drys out by June or so into lots of fuel on the ground just waiting for a lightning stroke or cigarette butt and bang, huge fires, made worse in the interiour by all the Pine beetle kill. The Pine Beetles here are another problem, winters seldom see temperatures of minus 40 for a week to kill them off.
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I think it was back in the '70's when it was recognized and methods were changed.
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Well, in many countries the excess biomass is removed.. it is called forest management.
Yes, and it's not a secret why (Score:5, Insightful)
As someone who lives and has lived smack dab in the fiery region, and who moved out of a house in Lake County, CA only a few weeks before it was consumed by flames, I've been in some of the forests in question (like the Mendocino National Forest) and I can tell you first hand that the problem is the undergrowth. The natives suppressed it with regular intentional fires for millennia. California created laws to prevent this in the name of private property rights, and now we are reaping the just rewards. When you let the undergrowth pile up and create a fuel load, the resulting burns are sufficiently severe to kill everything back. And if you don't trap soil after it's exposed, it tends to run away into waterways and be carried to the ocean where it causes still more problems.
This is specifically and only a failure of forest management, which is tied to our unrealistic imaginings of sustainable land use. It is simply not sustainable to build flammable homes in the middle of forests, because you then have to try to prevent fires to protect them. And since we have done the same things for the same reasons in much of the rest of the nation as well (essentially anywhere we didn't clear cut enough times to remove the forests) we are now beginning to experience the same problems in other states.
Re: Yes, and it's not a secret why (Score:2)
Colorado has only mild drought, trending better (Score:2, Informative)
Problem is, even back then, it was obvious drought was here.
It's always better to let trees handle themselves, humans (and especially government humans) can only fuck things up (as demonstrated by California).
Colorado does not have much of a drought problem [unl.edu], and it's better to let trees deal with that as they always have. If you look at historical data Colorado did have more of a drought problem before it's coming out of now.
Re: Colorado has only mild drought, trending bette (Score:2)
Re: Incorrect (Score:2)
you are full of shit if you did not realize we were in a drought clear back in the 00s.
Re:Yes, and it's not a secret why (Score:4, Interesting)
As someone who lives and has lived smack dab in the fiery region, and who moved out of a house in Lake County, CA only a few weeks before it was consumed by flames, I've been in some of the forests in question (like the Mendocino National Forest) and I can tell you first hand that the problem is the undergrowth.
To make matters worse, an increasing amount of that undergrowth is non-native vegetation that burns like crazy. One of the worst offenders is cheatgrass, which dries out earlier in the season, burns hotter, and recovers faster than native grasses.
Controlled burns are essential to undergrowth management. But unless the non-native plants are eradicated, those burns may actually make the problem worse over time.
Re:Yes, and it's not a secret why (Score:5, Informative)
Its amazing. The reservoirs in that area are at historic lows, some nearly running dry, and huge numbers of people are denying it. When it gets so dry that human populations have to migrate, half of us will still deny the science and blame obama and george soros.
Don’t worry - I’m no longer advocating for environmentalist issues. I’ve given up on human ability to mitigate this. Adapt or die are our only options at this point. 500 years from now, history books will describe this sorry affair as the triumph of our animal instincts to consume every resource available, consequences be damned, over our rational understanding of science.
Re:Yes, and it's not a secret why (Score:5, Informative)
Not arguing that crappy forest management hasnt contributed to the problem. But have you read the news lately about the lack of rainfall in that area?
It's been relatively rainy this year. California is always in a perpetual cycle of periodic and recurring drought. This is why the redwoods were sustainable here and the pines aren't. The Sequoias used to cover the entire coast range (and similar) literally all the way from around Point Sur to well up into Canada. They get their water from fog, so they're not dependent on rainfall, and drought is irrelevant to them.
I'm not saying the problem isn't exacerbated by AGW, of course it is. But California's ecology was not just resistant to but evolved for drought cycles before it was perturbed through forest mismanagement.
No, it was a dry year (Score:3)
It's been relatively rainy this year.
What? No it hasnt, I live a bit South of Lake County and it most certain HAS NOT been a rainy year. We had one major whether event at beginning of the year that was an atmospheric river that brought in a good amount of rain and then we basically had nothing else in terms of real meaningful rain fall and now we're in our dry season where we wont see any rain until late fall.
While forest management certainly plays a role these fires have much more to do with the massive and extended drought we're experiencin
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Ugh, "whether" = weather
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I'm not talking about just Lake County, I'm talking about Mendo and Hum and so on. And there's been noticeable late rainfall this year.
We can expect more atmospheric rivers dumping what turns out to be flood waters because of the reduction in trees. Trees literally cause rain to occur for a variety of reasons. Where there's no trees, the clouds tend to pass over without opening because of the lack of water from their respiration (and evaporation of moisture held in healthy soil) and because of a reduction i
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This whole region is some of the worst hit drought wise in the entire country right now. https://weather.com/news/clima... [weather.com] . If you scroll down a bit in my link you'll notice a color coded map of the US depicting rain fall for the year and the region of NorCal we're discussing is shown as the worst drought hit in the country as of May and there's absolutely no way that rain was made up for during the summer around here.
So as I was getting at, no it has not been rainy around here this year.
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Precip records, lake county, ca [weather.gov]
and Humboldt
Precip records, humboldt county, ca [weather.gov]
Mendocino is down 90-75% for the same period
Precip records, mendo county, ca [weather.gov]
That's a fun site to move the levers on. Never wonder or argue about precipitation accumulation again! And no pan or messy oven to clean up.
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High five for you, good resource. I'm a good bit disappointed having to lecture someone who claims to be of the region on rain though. Seems like I shouldnt need a resource like this for someone claiming large volumes of rain in a region down 90-75% rainfall for the year. Some people just have their heads up their asses I guess though.
Relative to what? (Score:2)
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Sequoia's haven't been native to Canada (or Washington State) for millions of years. They're too sensitive to frost due to the high water content of their tissues.
Not too many fog forests either, at least here in BC.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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The question to ask is what happened during the big droughts about 1000 years ago? The Medieval Warm Period in Europe was the Medieval Drought Period from CA to Central America. It collapsed the Mayan civilization.
So how do the CA forests get through that? What dried out and went to steppe, did anywhere get wetter? There has been quite a lot of research on that climate swing, what to expect now should be outlined by what did happen then.
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There were three Medieval warm periods, depending what you call Medieval.
None of them overlaps in time with the North American drought periods. And most likely the Maya where not affected by it anyway, as they were in middle/south America.
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"In the Americas, the climatic period 1000-1300 AD saw the culmination of very different changes to its climate. These had begun in the first half of the first millennium; a slow drying that developed over the following centuries and reached its apogee between 900-1300 AD.
In both California's Sierra Nevada mountains and in Patagonia, evidence recovered from the beds of deep lakes (trees that grew for well over a century or two on the lake-floor and died when the waters returned, human artifacts etc) show th
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Adapt or die are our only options at this point. 500 years from now, history books will describe this sorry affair as the triumph of our animal instincts to consume every resource available, consequences be damned, over our rational understanding of science.
Its cute you think History books will exist 500 years from now and have any mention of what the blip-in-time bunch of morons living here now were doing.
Re: Yes, and it's not a secret why (Score:2)
The best science we have is that California's natural state is megadrought territory and the late 19th and entire 20th century was abnormally wet for the area.
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it is completely irrelevant what will happen in 500 years, it may as well be 500000 years or 50000000000000 years, still completely irrelevant in reality, there is only now.
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If we are speaking from a scientific perspective, the region has ALWAYS been much drier, with a relatively wet century or three right when non maybe humans showed up.
What you're seeing is California and the region turning back into what it historically USUALLY was.
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Timber industry doesn't help, all the old growth gets harvested and canopies go lower.
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No, the exact opposite is contributing to the problem. The eco-nuts have prevented logging of the dead and dying trees providing massive amounts of fuel when fires do come along.
It's not the laws that stopped controlled burns (Score:2)
Basically you can thank Austerity politics and tax cut culture. Budgets got cut for anything that wasn't an imminent threat and emergency. No maintenance is done because nobody's gonna pay for it. When a fire's about to trash a city you can get politicians to pony up though.
Oh, and as other's pointed out, the worst drought in US history has a teensy bit to do with it too. But a
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We're talking about different things. You're talking about recent history. I'm talking about California's earliest days as a state, and the dominionist origins of our nation (California definitely included.)
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There are many invasive plants in the Santa Cruz mountains and similar areas that controlled burns are not really feasible anymore. For example, Scotch Broom is quickly displacing shorter less flammable native plants and goes up like gasoline, igniting the forest canopy.
I have a great idea. (Score:2)
Seek help for your illness, you can't beat it alone.
Colorado has same problem. (Score:5, Insightful)
It's a small price to pay (Score:1, Insightful)
Ask yourself, do you really want to live in a world with trees rather than a world where Joe Manchin can derail climate change plans for the nation to maintain his fossil fuel wealth? What have trees ever done for us? /s
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Government at all levels struggles with forest management but all in on spending for "climate change plans" because that is easier! Right?
Point is that the people who complain that all the fires are caused by forest management, and normal cycles start looking like quite the idiots when it becomes clear that forests aren't recovering. Here's a hint: The forest didn't grow thanks to human management. We weren't here 5000 years ago backburning the undergrowth carefully.
What we have done however is fucked up the climate. But sure, forest management is it exclusively. It can't have any impact due to climate change despite what the scientists say.
PERMANENT doesn't mean what you think it does (Score:2)
Re: PERMANENT doesn't mean what you think it does (Score:2)
You're a fucking idiot. Geologically speaking California's natural state is that of drought. The 20th century was abnormally wet for the area.
So that's why the evangelicals (Score:2)
Weed plantations (Score:2)
List of American National Parks... (Score:2)
... to see before climate change destroys their main attraction:
1. Glacier National Park
2. Redwood National Park
Any others?
In other newsâ¦. (Score:2)
Piping massive amounts of water out of the local ecosystem to the LA area so it can be dumped into the ocean disrupts the water table. Who knew!
Bad forest management is the cause (Score:1)