West’s forests will never be the same

by Paul VanDevelder




Last year's Indian summer fires in Montana were so intense, so awesome in their fury, that they even spooked veteran firefighters. Pilots dumping retardant on the Jungle Fire southeast of Livingston, Mont., reported flames jumping 500 feet above the tree line. For comparison, imagine a wall of flames leaping over the Washington monument. Hotshots, those elite firefighters delivered to fire lines from the air, dropped their shovels and gaped. What they were seeing, as super-dry fuel morphed into explosive gas, was a fundamental change now taking place in the chemistry of our forests.

That was right about the time former Montana Sen. Conrad Burns, R, called a group of exhausted firefighters lazy, good-for-nothing layabouts. It turned out that the crew was just catching some Zs on an airport tarmac after coming off a 36-hour stint on the fire line. This summer, Sen. Burns was gone; Hotshots were busier than ever.

I have a clear memory of that episode because I was working on a story about climate change, and climate modelers at NASA’s Goddard Institute told me that all of their predictions for climate change were accelerating. A couple of years ago, the low end on the projected increase in global temperature was 1.5 degrees centigrade. That window, a best-case scenario in the climate models, is now closed. The bottom limb of the arc is at now at 2 degrees centigrade. The physicists who watch these models, as data pour in from reporting stations around the world, have their fingers crossed. The consensus among scientists is that if we hit 3 degrees centigrade hotter, we need to start looking for another planet.

What the NASA people were finding seemed to correlate with close observations of a friend of mine, in Billings. Bob Ruble, a longtime resident of the Yellowstone Valley, told me that timber on his property has been tested, and it is now drier than kiln-dried lumber. “This entire region seems to be readjusting to desert-like conditions,” he says.

Rich Cronn, a research geneticist based at the U.S. Forest Service lab in Corvallis, Ore., agrees. “Plant species across the West are under an enormous amount of stress,” says Cronn. ”Conditions that once made life possible for a lot of species in marginal areas are changing very quickly. Fifty years from now, most of our forests are going to look very different than they do today.”

How different? One answer is that they might be gone. For a forest, climate change means two things -- bigger fires, and lots more of them. Meanwhile, Cronn says, “We’re all working on the models that will give us a better understanding of what’s coming next. It’s a fluid situation.”

Cronn and most of his colleagues believe that forests will begin to die off, and first to go will be the forests of Southern California, New Mexico, and Arizona. That’s because very few species in those forests have developed fire tolerance. Next, high-elevation conifer forests in the Southwest are virtually certain to vanish. That means the sparsely wooded islands of trees across the high country of New Mexico, Colorado, Arizona, Nevada and California could be gone in a generation. When the last Ice Age retreated thousand of years ago, the world it left behind allowed those stands of white and limber pines to take root and flourish. Today, say Cronn and his colleagues, those conditions are gone.

“High-elevation forests will have a tough time coming back if they burn,” Cronn says. “The conditions necessary for seedling survival just aren’t there.”

That means unless something unforeseen happens, the entire high-country ecosystem in the West is going to undergo radical change, including the dislocation of thousands of wildlife species for whom these forests are home. If and when the island forests of conifers are lost to fire, they’re not going to reseed. Grasslands will quickly move up in elevation and take over.

Mature conifer forests that don’t burn in coming decades will probably survive the initial change in conditions, says Cronn, but they won’t form a beachhead against climate change because those trees won’t reseed, either.

“Even if they survive, they won’t be able to replace themselves, so when they die off -- that’s pretty much the end of the road. These forests won’t be coming back any time soon,” Cronn says.

So if you happen to be looking for a job with longtime security, say, for the next 50 years, you might look into the Hotshots. They’re going to be busy.

Writers on the Range is a service of High Country News in Paonia, Colorado (hcn.org) Paul VanDevelder is a writer in Corvallis, Oregon, where he is working on a new book, Savages and Scoundrels, for Yale University Press. © High Country News