Conservation

A long history of political and legal action built on a foundation of scientific evidence resulted in the near elimination of old-growth logging in the western Cascades by the turn of the century. This success was won due to the dedication and hard work of thousands of individuals and hundreds of organizations, and is now being codified into official United States policy. A formal rule-making process is underway (December, 2023) to effectively ban old-growth logging in all national forests through a nationwide forest plan amendment.

While this policy development is hugely important, and should be reinforced through legislative action and extension to mature forests, it is in some ways a closing chapter to the long-running saga of old-growth logging in the Pacific Northwest. But as the threat from logging recedes, the threat from a new era of wildfire stoked by climate warming has emerged. And the large, severe fires that have become alarmingly frequent are not bound by formal policy, judicial rulings, or lines on maps.

Recent changes in fire regimes are confronting closely held beliefs that old-growth forests are highly resistant to fire, and that fire is a natural process so should be left largely unhindered. But the experience of the last few years in the western Cascades clearly demonstrates that old-growth forests are indeed highly susceptible to wildfire when fuels are excessively dry, which has become common (see Wildfire and 25 Years of Trailside Change.) After all, one of the defining characteristics of old-growth forests is a massive amount of live and dead vegetation, known by some as fuel. Philosophers can debate the meaning of ‘natural’ in our highly modified environment, but the reality is the pace of ecosystem change due to human-caused climate warming, is far outside historical rates of change as experienced over the lifetime of our remnant old forests.

It would be easy to see climate change as so overwhelming that efforts to prevent or mitigate damage to old-growth forests are bound to be futile. And agency capabilities to make a meaningful difference are also rightfully subject to question. The experience of recent decades shows that protecting old forests from wildfire is profoundly challenging, sometimes impossible, and never guaranteed. But if we hope to retain old forests on the landscape for the next half century, a proactive approach is warranted. Resignation without action is deeply dispiriting.

An important first step is to elevate the priority of protecting old forests into the top tier of wildfire values-at-risk along with protecting life and property. Surely, protecting old forests is as or more important than protecting many types of property and infrastructure. It takes 500 years to replace a 500-year-old forest, but even the most expansive campground can be replaced in a decade or less.

The meaning of protection varies greatly among forest types. In dry forest types, protection means reducing fuel loads and reintroducing fire so that future wildfires burn at lower severity and increase the likelihood that old fire-resistant trees will survive. In wetter forest types, protection often means that fire should be excluded from old-growth stands to the extent feasible since fire will likely destroy the very values at risk due to the extremely high fuel loads in these forests.

There are many strategic and tactical decisions made during wildfire incidents that should be evaluated with respect to protecting old-growth forests. Important factors include the location of primary and secondary control lines; location and type of fuel treatments, especially including burn-out operations; and fundamental decisions about passive versus aggressive responses.

Agencies are also spending large sums of money on fuel treatments outside of active wildfire incidents to reduce the severity of wildfire effects, and to enhance their ability to mount effective wildfire responses. The high-value of old-growth forests should be an important criterion that guides the location and type of fuel treatments. In dry forest types, fuels treatment can enable prescribed and less-severe wildfire and potential restoration of more fire-resistant old forests. In wetter forest types, fuels treatment in old growth will likely destroy the very values at risk, and should be limited to boundary locations that might support fire containment operations.

Both wildfire incident response and fuel treatment planning would be enhanced by maps identifying the highest priority old-growth groves. Identified groves might consist of the remaining large, intact blocks of old growth that because of their location and surroundings have a higher probability of being effectively protected during a wildfire incident. This could be due to the topography and slope position of the grove, or due to roads or other features that support firefighting response. Fuels treatments implemented prior to wildfire might enhance the ability of firefighting operations to protect old forests in some situations.