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  • As you've probably noticed,

  • in recent years, a lot of western forests have burned

  • in large and destructive wildfires.

  • If you're like me --

  • this western landscape is actually why my family and I live here.

  • And as a scientist and a father,

  • I've become deeply concerned about what we're leaving behind

  • for our kids, and now my five grandkids.

  • In the US, an area that's larger than the state of Oregon has burned

  • in just the last 10 years,

  • and tens of thousands of homes have been destroyed.

  • Acres burned and homes destroyed have steadily increased

  • over the last three decades,

  • and individual fires that are bigger than 100,000 acres --

  • they're actually on the rise.

  • These are what we call "megafires."

  • Megafires are the result of the way we've managed this western landscape

  • over the last 150 years

  • in a steadily warming climate.

  • Much of the destruction that we are currently seeing

  • could actually have been avoided.

  • I've spent my entire career studying these western landscapes,

  • and the science is pretty clear:

  • if we don't change a few of our fire-management habits,

  • we're going to lose many more of our beloved forests.

  • Some won't recover in our lifetime

  • or my kids' lifetime.

  • It's time we confront some tough truths about wildfires,

  • and come to understand that we need to learn to better live with them

  • and change how they come to our forests,

  • our homes

  • and our communities.

  • So why is this happening?

  • Well, that's what I want to talk to you about today.

  • You see this forest?

  • Isn't it beautiful?

  • Well, the forests that we see today

  • look nothing like the forests of 100 or 150 years ago.

  • Thankfully, panoramic photos were taken in the 1930s

  • from thousands of western mountaintop lookouts,

  • and they show a fair approximation

  • of the forest that we inherited.

  • The best word to describe these forests of old is "patchy."

  • The historical forest landscape was this constantly evolving patchwork

  • of open and closed canopy forests of all ages,

  • and there was so much evidence of fire.

  • And most fires were pretty small by today's standards.

  • And it's important to understand that this landscape was open,

  • with meadows and open canopy forests,

  • and it was the grasses of the meadows

  • and in the grassy understories of the open forest

  • that many of the wildfires were carried.

  • There were other forces at work, too, shaping this historical patchwork:

  • for example, topography, whether a place faces north or south

  • or it's on a ridge top or in a valley bottom;

  • elevation, how far up the mountain it is;

  • and weather, whether a place gets a lot of snow and rain,

  • sunlight and warmth.

  • These things all worked together

  • to shape the way the forest grew.

  • And the way the forest grew shaped the way fire behaved

  • on the landscape.

  • There was crosstalk between the patterns and the processes.

  • You can see the new dry forest.

  • Trees were open grown and fairly far apart.

  • Fires were frequent here, and when they occurred,

  • they weren't that severe,

  • while further up the mountain,

  • in the moist and the cold forests,

  • trees were more densely grown and fires were less frequent,

  • but when they occurred, they were quite a bit more severe.

  • These different forest types, the environments that they grew in

  • and fire severity -- they all worked together

  • to shape this historical patchwork.

  • And there was so much power

  • in this patchwork.

  • It provided a natural mechanism

  • to resist the spread of future fires across the landscape.

  • Once a patch of forest burned,

  • it helped to prevent the flow of fire across the landscape.

  • A way to think about it is,

  • the burned patches helped the rest of the forest

  • to be forest.

  • Let's add humans to the mix.

  • For 10,000 years, Native Americans lived on this landscape,

  • and they intentionally burned it -- a lot.

  • They used fire to burn meadows and to thin certain forests

  • so they could grow more food.

  • They used fire to increase graze

  • for the deer and the elk and the bison that they hunted.

  • And most importantly, they figured out

  • if they burned in the spring and the fall,

  • they could avoid the out-of-control fires of summer.

  • European settlement -- it occurred much later, in the mid-1800s,

  • and by the 1880s, livestock grazing was in high gear.

  • I mean, if you think about it, the cattle and the sheep ate the grasses

  • which had been the conveyer belt for the historical fires,

  • and this prevented once-frequent fires from thinning out trees

  • and burning up dead wood.

  • Later came roads and railroads, and they acted as potent firebreaks,

  • interrupting further the flow of fire across this landscape.

  • And then something happened which caused a sudden pivot

  • in our society.

  • In 1910, we had a huge wildfire.

  • It was the size of the state of Connecticut.

  • We called it "the Big Burn."

  • It stretched from eastern Washington to western Montana,

  • and it burned, in a few days, three million acres,

  • devoured several towns, and it killed 87 people.

  • Most of them were firefighters.

  • Because of the Big Burn, wildfire became public enemy number one,

  • and this would shape the way that we would think about wildfire

  • in our society

  • for the next hundred years.

  • Thereafter, the Forest Service, just five years young at the time,

  • was tasked with the responsibility of putting out all wildfires

  • on 193 million acres of public lands,

  • and they took this responsibility

  • very seriously.

  • They developed this unequaled ability to put fires out,

  • and they put out 95 to 98 percent

  • of all fires every single year in the US.

  • And from this point on, it was now fire suppression

  • and not wildfires

  • that would become a prime shaper of our forests.

  • After World War II, timber harvesting got going in the west,

  • and the logging removed the large and the old trees.

  • These were survivors of centuries of wildfires.

  • And the forest filled in.

  • Thin-barked, fire-sensitive small trees filled in the gaps,

  • and our forests became dense, with trees so layered and close together

  • that they were touching each other.

  • So fires were unintentionally blocked by roads and railroads,

  • the cattle and sheep ate the grass,

  • then along comes fire suppression and logging, removing the big trees,

  • and you know what happened?

  • All these factors worked together

  • to allow the forest to fill in,

  • creating what I call the current epidemic of trees.

  • (Laughter)

  • Go figure.

  • (Laughter)

  • More trees than the landscape can support.

  • So when you compare what forests looked like 100 years ago and today,

  • the change is actually remarkable.

  • Notice how the patchwork has filled in.

  • Dry south slopes --

  • they're now covered with trees.

  • A patchwork that was once sculptured by mostly small

  • and sort of medium-sized fires

  • has filled in.

  • Do you see the blanket of trees?

  • After just 150 years,

  • we have a dense carpet of forest.

  • But there's more.

  • Because trees are growing so close together,

  • and because tree species, tree sizes and ages

  • are so similar across large areas,

  • fires not only move easily from acre to acre,

  • but now, so do diseases and insect outbreaks,

  • which are killing or reducing the vitality

  • of really large sections of forest now.

  • And after a century without fire,

  • dead branches and downed trees on the forest floor,

  • they're at powder-keg levels.

  • What's more, our summers are getting hotter

  • and they're getting drier

  • and they're getting windier.

  • And the fire season is now 40 to 80 days longer each year.

  • Because of this, climatologists are predicting

  • that the area burned since 2000

  • will double or triple

  • in the next three decades.

  • And we're building houses in the middle of this.

  • Two recently published studies tell us

  • that more than 60 percent of all new housing starts are being built

  • in this flammable and dangerous mess.

  • So when we do get a fire,

  • large areas can literally go up in smoke.

  • How do you feel now

  • about the forest image

  • that I first showed you?

  • It scares the heck out of me.

  • So what do we do?

  • We need to restore the power of the patchwork.

  • We need to put the right kind of fire

  • back into the system again.

  • It's how we can resize the severity of many of our future fires.

  • And the silver lining is that we have tools

  • and we have know-how to do this.

  • Let's look at some of the tools.

  • We can use prescribed burning to intentionally thin out trees

  • and burn up dead fuels.

  • We do this to systematically reduce them and keep them reduced.

  • And what is that going to do?

  • It's going to create already-burned patches on the landscape

  • that will resist the flow of future fires.

  • We can combine mechanical thinning with some of these treatments

  • where it's appropriate to do so,

  • and capture some commercial value

  • and perhaps underwrite some of these treatments,

  • especially around urban areas.

  • And the best news of all is that prescribed burning produces

  • so much less smoke than wildfires do.

  • It's not even close.

  • But there's a hitch:

  • prescribed burning smoke is currently regulated under air quality rules

  • as an avoidable nuisance.

  • But wildfire smoke?

  • It simply gets a pass.

  • Makes sense, doesn't it? (Laughs)

  • So you know what happens?

  • We do far too little prescribed burning,

  • and we continually eat smoke in the summers

  • from megafires.

  • We all need to work together to get this changed.

  • And finally, there's managed wildfires.

  • Instead of putting all the fires out,

  • we need to put some of them back to work

  • thinning forests and reducing dead fuels.

  • We can herd them around the landscape

  • when it's appropriate to do so

  • to help restore the power of the patchwork.

  • And as you've probably figured out by now,

  • this is actually a social problem.

  • It's got ecological and climate explanations,

  • but it's a social problem, and it will take us humans to solve it.

  • Public support for these tools is poor.

  • Prescribed burning and managed wildfires are not well-supported.

  • We actually all simply want fires to magically go away

  • and take that pesky smoke with them, don't we?

  • But there is no future without lots of fire and lots of smoke.

  • That option is actually not on the table.

  • Until we, the owners of public lands, make it our high priority

  • to do something about the current situation,

  • we're going to experience continued losses to megafires.

  • So it's up to us.

  • We can spread this message to our lawmakers,

  • folks who can help us manage our fires

  • and our forests.

  • If we're unsuccessful,

  • where will you go to play

  • when your favorite places are burned black?

  • Where will you go

  • to breathe deep

  • and slow?

  • Thank you.