FIRE IS NOT THE ENEMY PART II:
Ken Carloni, PhD.
The 2013 Douglas Complex Fires Revisited
New science reverses conventional wisdom that old growth forests burn more severely than plantations.
Four years ago, I wrote an article for the Summer 2014 100 Valleys entitled “Fire Is Not The Enemy” analyzing the Douglas Complex fire that burned through a BLM/private industry checkerboard northwest of Glendale, OR in 2013. This was in response to a number of articles in the Roseburg News Review and elsewhere decrying the “destruction” of the forests burned in those fires. Those sympathetic to the timber industry were calling for aggressive snag removal on public lands and for the conversion of old growth forests to tree farms to supposedly prevent such fires in the future. I provided a number of satellite images of forest stands and compared them with fire intensity maps showing this thinking to be exactly the wrong approach to creating and maintaining healthy, fire-resistant forests.
In the years since, I have given several public presentations expanding that analysis to most of the major fires that have burned on the Umpqua since 2002. In all of them, the visual evidence is striking: dense, even-aged plantations with their contiguous, highly flammable fine fuels are far more likely to suffer high mortality crown fires than uneven-aged, multi-canopied primary forests. Rather than contributing to the spread and severity of the fire, old growth forests did just the opposite by “knocking down” the flames and turning them into ground fires.
These low to moderate intensity under-burns create valuable habitat for fire-dependent species while removing built-up fuel to create fire-resilient landscapes. The majority of the Douglas Complex fire increased the ecological health of unmanaged public land, but decreased the health of plantation stands. This same scenario played out again in the Stouts Creek fire, the Cable fire, the North Umpqua Complex, and other fires in the region.
While that pattern is clearly visible to the eye, no rigorous scientific study had been done to provide the spatial statistics necessary to debunk the conventional “wisdom” that fuel volume is what determines fire spread and severity rather than fuel structure. I had already upgraded my GIS software with plans to do that spatial analysis on Umpqua fires this summer when I received a copy of an April 2018 paper by Harold Zald from Humboldt State University and Christopher Dunn from Oregon State University entitled “Severe fire weather and intensive forest management increase fire severity in a multi-ownership landscape”. The “multi-ownership landscape” they analyzed? The Douglas Complex fire.
The Zald and Dunn study confirms what I and others have been saying (and the industry has been denying) for years: after weather, the biggest predictor of fire severity is “stand age and ownership” and that “…pre-fire forest biomass [was] not an important predictor of fire severity”. The researchers conclude that “…intensive plantation forestry characterized by young forests and spatially homogenized fuels, rather than pre-fire biomass, were significant drivers of wildfire severity.”
Immediately after the Douglas Complex fire was out, private industry began to aggressively log the burned timber, including the non-merchantable young plantations, and replanted them in the same tightly spaced rows of seedlings. Replanting damaged plantation stands with another dense monocrop will simply set the stage for another dangerous conflagration. For example, The 1987 Bland Mt. Fire that burned mostly in young second growth near Canyonville was replanted in closely spaced soldier rows only to burn hard again in 2004, with two smaller fires in recent years.
The call for systematic snag removal on public lands (repeated again just last week in a News-Review letter to the editor) doesn’t make sense either — snags don’t “attract” lightning. The strikes that started the Douglas Complex hit on the ridges (the highest points on the landscape) in both primary forest and plantations in about equal numbers. In a heavily managed landscape, snags are more likely to be hit simply because the surrounding trees have been logged and those snags are now the tallest objects on the landscape by default.
|Fire Mosaic. This image shows the difference in the effects of the Douglas Complex on different stand structures. The only green trees in the burned areas are in the old growth BLM stands. The private plantations suffered almost complete mortality.|
Felling snags that are burning and/or are a serious danger to firefighters is necessary for safety reasons, and no one argues that they shouldn’t be cut under those circumstances. But aggressive pre-fire snag removal will do nothing to prevent future fires and will remove a critical ecological resource: large snags are home to cavity nesting birds (who feed on tremendous numbers of potential pest insects) and a myriad of other animals and fungi that play important roles in maintaining healthy ecosystem dynamics.
Rather than continuing to fight a losing battle against wildfire, it’s time to change our mindset from fire fighting to fire management. Bringing prescribed fire back into our forests in a systematic, ecologically beneficial manner will be far cheaper and more effective than letting lightning or careless humans dictate when and where fires burn.
The Zald and Dunn study is a timely antidote to the steady drumbeat of disinformation from county commissioners and Wall Street corporations that continue to fan the flames of fire hysteria and drown out the voices of scientists and historians who remind us that fire has and will continue to play an integral role in the health of our forests. I end this article with the same quote from noted fire historian Stephen J. Pyne that I began my 2014 article with:“Messed-up forests will only yield messed-up fires.”