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Living Fire: Not your grandparents’ landscape

by Timber Press on May 9, 2017

in Natural History, Regional

Increasingly, the much-loved panoramas of the American West are infused with smoke. Yet there’s much more than scenery at stake here. In a single week during September 2015, the federal government spent more than $240 million battling out-of-control wildfires. Photo by Tim Mossholder.

An excerpt from Land on Fire: The New Reality of Wildfire in the West by Gary Ferguson.

As mourning rolls across a slice of ponderosa and douglas-fir forest in southern Colorado one August day, thin sheets of clouds are dissolving into tatters and then scattering in the wind. More clouds come later, in the heat of the afternoon, some with dark curtains hanging from their bellies, telltale signs of rain; but the air is so warm and dry that no drops reach the ground. Then in midafternoon, a bolt of lightning blasts out of the sky, discharging at the top of a 60-foot ponderosa pine snag on a steep south-facing slope. No one is around to see the hit, the brilliant flash of the lightning bolt carving a channel through the air with such force that when the channel fills again, it creates an ear-shattering boom of thunder.

The dry wood explodes into the surrounding forest, sending a light spray of sparks into the air. As the base of the snag smolders, a thatch of dry fescue grass, strewn with bits and pieces of fallen limbs, begins to burn. Fanned by a gusty wind—common to dry lightning events—the flames start to spread. Embers begin to pop and blow. One lands in the shallows of a small creek, fizzling with a soft hiss. Another falls on a slab of granite and burns itself out. But still another flies about 20 feet to land in a patch of cheatgrass and small branches, the latter blown off trees killed in a pine bark beetle infestation.

Thus begins another wildfire in the American West.

In the not-so-distant past, when wildfires burned unrestrained, they played an essential role in shaping the forests. To better comprehend this role, it might help to take a look at one specific kind of forest community , found not only in southern Colorado but also from New Mexico to Montana, west through Idaho and Utah and parts of Nevada to Oregon, Washington, and California. The centerpiece of this community is the ponderosa pine. The ponderosa’s signature features—beautiful cinnamon-colored bark, which on mature trees is thick and furrowed, as well as the tree’s ability to self-prune, which means dropping its lower branches when they no longer have access to the sun—are in fact evolutionary adaptations linked to wildfire. The tree’s thick bark allows it to withstand flames without suffering damage to the cambium layer (the part of the tree that produces both new bark and wood), while the self-pruning of lower branches keeps ground fires from climbing the tree and killing it by destroying the upper foliage—the crown.

Clouds of smoke loomed over Colorado Springs on the first day of the June 2013 Black Forest Fire, which killed two people, destroyed more than five hundred homes, and forced the evacuation of thirty-eight thousand people. Photo by Rachael Botkin (Newhart).

When early European explorers praised ponderosa pines, calling them regal, swooning over the sun-dappled parklike groves that were so easy to travel through on horseback and sometimes even by wagon, they were celebrating a forest thoroughly shaped by wildfire. Not only fire in its more extreme form as scorching walls of flame marching across the mountains, but also the far more frequent low-to-moderate-intensity regular burns foresters today call stand-maintenance fires.

When stand-maintenance fires occurred, burning through many western woodlands roughly every ten to fifteen years, what got burned up were the lower branches the trees had dropped and the occasional toppled tree, along with needles, cones, and small plants of the forest floor. Meanwhile, if diseases or insects came along and wiped out patches of mature trees, as those trees fell they left holes in the canopy. In little time, young pines would begin sprouting in those holes and vying for dominance, eventually replacing the fallen trees and closing the canopy again. On it went like this, to a greater or lesser degree, often for centuries at a time.

But beginning in the latter half of the 1800 s, use of the western forests by humans greatly intensified. Big changes followed. Grazing livestock, for example, altered the plant communities on the forest floor, as the hooves of cattle provided seedbeds in which clusters of young, shade-tolerant trees could gain purchase. This alone helped to make the forest a more crowded place—something that would have major consequences when fires came along. In addition, massive logging operations got under way, with loggers felling mostly the largest, oldest trees; what remained were tighter bunches of young-to-middle-aged timber. But probably nothing had more of an effect on the fires we see burning today than the fact that in the early twentieth century we began eighty years of fervent effort to put out every fire we could get our axes and shovels and saws on.

An air tanker drops fire retardant to slow the advance of the Chelan Complex Fire, which consumed nearly 89,000 acres just south of Chelan, Washington, in September 2015. Photo by Ben Brooks.

More about that later. But for now you may be wondering how we know what the forests looked like before Europeans showed up and how we’ve gained knowledge of the way wildfires have shaped what we see today. The answers are held in some painstaking scientific research, research that involves going to the trees themselves, rediscovering what many indigenous cultures around the world have pointed out—namely, that trees are the keepers of stories about the landscape.

A first step in unraveling the burns of long ago is to examine a given section of forest for so-called fire scars. Whenever sufficient heat from a passing fire penetrates the bark of a tree, it causes death in a section of the underlying cambium layer; from then on, those dead cells show up as a lesion, or fire scar. Hot fires on the ground likewise cause damage to certain sections along the base of a tree—scars that will last either until the tree rots or some other damage occurs. By studying a number of trees in a small area, scientists can piece together information about the size of past fires, the direction they were traveling, even the fuel load on the forest floor at the time of the burns.

Once this fire scar data is collected, it’s compared to annual tree ring records, which provide a yearly account of the general growing conditions across the lifetime of an individual tree. In this way fire scars can be dated—not just to the year they occurred but often to the very month. Thus the fire history of a forest, even an entire mountain range, can be reconstructed with surprising accuracy. These kinds of historical records, in turn, have allowed us to get a better sense of the degree to which both the frequency and intensity of fires have increased over the past couple of hundred years.

Fire season in the American West has surely changed, when it comes to heat, drought, and the resulting inevitable flush of wildfire, the new millennium has brought a run of trouble-filled summers. Trouble at the edges of inland cities in central and southern California, where flames have rolled in from loose clusters of live oak and chaparral to devour hundreds of homes. Trouble too in the sweet-smelling Engelmann spruce and Douglas-fir groves outside ski towns like Vail and Jackson and Big Sky. Trouble on cattle ranches from Washington to Wyoming, where fires have roared out of the foothills to consume pasture and fences and barns. And trouble especially in a thousand forested subdivisions stretching from the western slope of the Sierra Nevada to the eastern slope of the Rockies, from the Sangre de Cristo Range of New Mexico to the Chugach Mountains of Alaska.

Even for those to whom wildfire has become familiar, it’s hard to comprehend the collective impact these burns are having on the landscapes and communities of the West. Not that long ago, 4,000-acre fires were a big deal. But now firefighters are routinely called out on burns three or four times that size. “I think about the big fire season in California back in 1987,” says highly experienced firefighter Matt Holmstrom, superintendent of the Lewis and Clark Hotshots in Great Falls, Montana. “And then the next year, massive burns in Yellowstone. They seemed like such exceptional years. And now they’re pretty much routine.”

Poignant scenes in such communities from California to Colorado have taken place in July and August of the drought years, in people’s driveways, as hundreds of men and women and kids have carried boxes and suitcases from their houses to the families’ cars or pickup trucks, making ready to drive away with precious pieces of their lives should word come down that wildfire is closing in and the time has come to evacuate.

And so it goes across the West. Life in a land of flames.

 

Gary Ferguson has written many books on nature and science including Hawks Rest, the first nonfiction work to win both the Pacific Northwest Booksellers Award and the Mountains and Plains Booksellers Award for Nonfiction, Decade of the WolfThe Great Divide, and The Carry Home. His articles have appeared in Vanity Fair, the Los Angeles Times, and other publications. His lectures on wilderness are a culmination of 30 years researching—and experiencing—the marriage of wild lands, history, myth, and narrative psychology. Visit him at wildwords.net.

 

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