San Diego Union Tribune: Dead forest trees threaten public safety

By David Bischel & Jeff Bowman:

State officials and forest owners say the current tree mortality epidemic that has killed more than 66 million trees statewide (with millions more at risk), significantly increases the risk of wildfire and call it an immediate threat to public health and safety.

The tree mortality epidemic we are experiencing is a combination of overcrowded forests and five years of drought, which weakens the trees’ natural defense mechanism and makes them unable to fight off bark beetles and other pests.

While the bark beetle has nothing to do with causing wildfires, when one does erupt, the drought-killed trees will burn faster, longer, hotter and more unpredictably — posing even greater danger to public safety and firefighters.

These wildfires to which California is becoming accustomed are devastating on many levels. Examples of catastrophic wildfires include the Rim Fire that burned more than 256,000 acres in Yosemite; the King Fire that burned 97,717 acres in Placer County; and, the state’s largest ever wildfire — the 2003 Cedar Fire in San Diego. These wildfires wipe out wildlife habitat; they release tons of greenhouse gases into the atmosphere; they threaten public safety; they threaten water and electric supplies; and they ultimately threaten lives.

If we leave excessive amounts of drought-killed trees on the forest floor, it will provide excess fuel for when a wildfire does come through. Research shows that excess fuel causes a wildfire to burn hotter and more severely.

They can burn so hot that they not only kill the trees, but sterilize the soil and seed stock, inhibiting natural regeneration and the soil’s ability to absorb water, leading to increased erosion in critical watersheds.

The effects of wildfire are not to be taken lightly. We are seeing a growing pattern of warmer temperatures, drought and more severe wildfires. In fact, California’s wildfire season is now considered to be a year-round season.

According to a 2012 study by Jay Miller and Hugh Safford, the number of large wildfires has more than doubled since 1950. In fact in 2001, 304,000 acres were burned in wildfires compared to more than 500,000 in 2014. They found that those wildfires were burning at a higher severity — having devastating impacts on our forested landscapes.

In 1986, high severity burns accounted for 21 percent of total acres burned. By 2010, that number had grown to 31 percent. And in the 2013 Rim Fire, 38 percent of the area burned was considered high severity. In the 2014 King Fire, 47 percent of the area burned was high severity — a growing trend we cannot afford to ignore.

Experts expect those number to increase with the additional fuel of 66 million drought-killed trees. Moreover, Stanford’s Carnegie Institute estimates that water stress in existing forests has contributed to another 58 million trees in serious risk of mortality.

The risks of wildfire far outweigh any perceived benefits that proponents may argue. While wildfire has always been a part of our ecosystem, those wildfires were less intense, mostly ground fires or small groups that help burn off the excess fuel. They didn’t decimate hundreds of thousands of acres in a single swath.

It’s why the governor proclaimed a state of emergency and issued an emergency proclamation to expedite the removal of millions of drought-killed trees. It’s why firefighting agencies are actively working to remove the dead trees in strategic areas of our state for public safety, and it’s why local governments are scrambling to protect their communities.

As California continues its sprawl into the rural urban interface, forested communities are at an increased risk.

We can leave them in the forest to let them burn when an errant cigarette or a dry lightning-storm comes through, or we can take proactive measures by removing them and turn them into renewable biomass energy, which reduces pollution by 98 percent when compared to open burning.

It seems like an easy choice — remove much of the wildfire hazard from communities and turn it into renewable energy. Biomass would help meet several state goals: The Renewable Portfolio Standard; AB 32 GHG reduction goals; and, the Governor’s Emergency Proclamation. Seems like a win-win.

We stand together in supporting efforts to expedite the removal of drought-killed trees in order to protect our communities and return our forests to a more healthy state — one that is more resilient to these types of natural disasters.

Bischel, a registered professional forester, is president of the California Forestry Association. Bowman, fire chief, Orange County Fire Authority, is a former San Diego City fire chief.

San Diego Union Tribune, July 27, 2016