Managing Forest Through A Rear View Mirror

Former chair of the U of Montana Economics Department, Tom Power, often noted that most rural communities in the West see their economies in a rear view mirror. They have no idea of what is driving their current economy, and often continue to support economic activities that may be detrimental to the new unfolding economic sectors. Long after activities like logging, ranching and mining are in steep decline and have already been replaced by other economic sectors like tourism, service industry, education, medical or transfer payments, many communities continue to think of their towns as logging towns, mining centers or ranching communities.

In a similar way, we see many land management agencies at the behest of timber company lobbyists, uninformed politicians and community leaders managing the public forests through a rear view mirror when it comes to fire policies. The climate that created the past forests is no longer operating. For instance, in California alone, the average temperature has risen 1.5 degrees since 1895. In the Southwest we are experiencing a 500 year drought—a drought unlike anything that shaped the forests that exists in this region today.

Due to climate change, we have warmer springs, hotter summers, more intense droughts, and overall higher wind speeds—all of these are ingredients that favor greater fire spread and severity, along with greater vulnerability to beetles, disease and other natural processes that create healthy forests. In the past decade or so we have experienced the warmest years since weather/climate data was collected in the 1880s.

Here’s a link to a recent study documenting how climate is affecting fires.

However, the rear view mirror story line is based on a different climate regime. It goes something like this. Prior to the advent of fire suppression, frequent, low severity fires kept forests open and park-like and fuel accumulations low. Fires burned through forests as often as every couple of years. However, with the advent of active fire suppression, fuels have grown and are responsible for large wildfires, beetle outbreaks and other calamities.

The proposed solution to reduce large fires is to log the forests to restore forests to the open, park like condition that are thought to have characterized the West prior to fire suppression. Bear in mind that even if we could reduce or eliminate large fires this would contribute to an even greater forest degradation since large blazes and beetle events are the prime mechanism for balancing trees with climatic conditions as well as the prime mechanism for recruiting dead trees and down wood into forest ecosystems.

But like the rear view mirror of community economies, new insights into fire ecology are challenging the old view about wildfire and forests, and finding this story line is far more nuanced than previously thought.

The new paradigm finds that fire suppression influence is greatly exaggerated, and likely only applies to very limited areas of the West dominated primarily by ponderosa pine—and even among ponderosa pine, the old paradigm is under challenge by some who argue that the standard view that low severity blazes were the norm may be misleading as well.

Fuels don’t ultimately control fire spread, rather it is climate/weather that affects fire severity and spread. You can have tons of fuels as exists in the Coast Range of Oregon but have few fires. Why? Unless you have the right climatic/weather conditions, you can’t get forests to burn. For much of the last few hundred years, the West was in the Little Ice Age where the climate was cooler and moister. Cool, moist weather hinders fire spread. Indeed, between the 1940s and 1990s, a time when big time fire fighting began with tankers, helicopters and smoke jumpers, the West was experiencing conditions that overall were cooler and moister than even the preceding decades and considerably less favorable for fire ignition and spread than the conditions we are experiencing today. Even in the driest forests like ponderosa pine, fires tended to be small, localized, and low severity, in part, because they could not become infernos readily.

When conditions for fire spread are poor, most fires go out whether we “suppress” them or not. Fire fighters may have taken credit for “putting out” the blaze, but most fires were destined to go out on their own anyway.

This same period of poor weather/climatic conditions for fire spread is exactly the same time when the “fire suppression” school of thought argues that successful fire-fighting efforts were creating accumulations of fuels and dense forest stand structure. Thus current forest condition can be explained by climatic factors rather than due to human influences.

Even more devastating to the rear view fire suppression story of frequent, low intensity blazes is that the theory simply doesn’t apply to the vast majority of major tree species and plant communities in the West.

Most forest species including Douglas fir, aspen, lodgepole pine, white pine, all fir and spruce species, hemlock, cedar, western larch, and various high elevation pines like whitebark pines have always had relatively long fire rotations, often hundreds of years between major fires. As a consequence, fire suppression, even if it were successful, has not been effective long enough to substantially alter these forest fires cycles and hence fuels. These forests were characterized by longer fire-free intervals that tended to burn as mixed to high severity fires.

In addition, new research is revising the fire regimes for many plant communities that previously were thought to have frequent low severity fires. For instance, not long ago, it was thought that mountain big sagebrush burned every 25-30 years, but new insights suggest the true fire rotation is more on the order of 100-150 years. Similar revisions fire regimes have been proposed for juniper woodlands and chaparral.

Indeed, the only common forest species that may fit the frequent, low severity fire story line is ponderosa pine. However, some fire ecologists now think that fire rotation was much longer even for ponderosa pine in some parts of the country and that stand replacement high severity fires even burned through these pine forests—at least occasionally.

Other factors that may have contributed to the rear view mirror view of fires are biased fire scar history studies that incorrectly attribute too many fires to an area due to flawed study designs. (It is too complicated to delve into here, but you can read more at https://www.thewildlifenews.com/2013/07/11/revisiting-fire-history-studies/)

This brings us to the current weather/climatic conditions. Even if the old rear view mirror explanation of fire behavior that claims prior to fire suppression fires were mostly low severity and frequent, such fire behavior was a product of weather/climatic conditions that existed during the Little Ice Age—a time when much of the globe experienced cooler, moister conditions.

Indeed, we now have weather/climatic conditions more analogous to the Medieval Warm Spell that preceded the Little Ice Age. During this period spanning the centuries roughly from 800 to 1300 AD climatic conditions were considerably warmer in northern climates, while extreme drought and high temperatures dominated more southern latitudes. This is the time when Vikings colonized Greenland because of the mild climatic conditions, while the Anasazi Indians abandoned their pueblo dwellings in the Four Corners region due to extreme drought.

Paleo fire history reconstructions based on methods other than fire scars show that large mega fires were the norm during this time period. Not surprisingly the Southwest is in the midst of a drought that we have not seen since the Anasazi left their cliff-side dwellings for permanent water sources along the Rio Grande. Is it really any wonder that we are seeing some of the largest fires ever recorded in this region?

Trying to manage our forests to restore conditions found in the 1800s when the climate was cooler and moister is a fool’s errand. Rather natural processes like wildfire, insects, and disease are already contributing to healthy forests by thinning trees, and shifting plant communities to the new climate realities. It does no good to look in the rear view mirror and try to recreate forest structure and conditions that dominated during an entirely different climate regime.

It’s time to recognize our forests are going to be different than the ones we have grown accustomed to and perhaps existed in the recent past. A rear view mirror approach to forest management is guaranteed to fail as have been the efforts of rural communities to hold on to their old economies in the face of changing economic realities.

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