Dead Sierra Nevada trees pose serious fire risk

BY NATHAN GRAVELINE, CHRIS TROTT AND JOHN BUCKLEY

Special to The Bee

Recently, The Modesto Bee ran an editorial acknowledging the enormity of the wildfire threat currently facing public and private lands across the West. (“Preventing forest fires is up to Congress,” July 7) In particular, The Bee accurately emphasized the urgent need for Congress to stop forcing the U.S. Forest Service to divert enormous amounts of the agency’s normal, budgeted funds to be spent fighting wildfires.

Those budgeted funds could actually reduce the potential damage and expense of future wildfires if they were spent on forest fuel reduction treatments such as thinning logging projects and prescribed burns.

In contrast to that positive and factual Bee editorial, a guest opinion piece by Chad Hanson in The Bee on July 6 ran under a headline claiming that the onslaught of bark-beetle-killed trees in the Sierra Nevada poses “no threat.”

Hanson misled readers by falsely claiming that millions of dead and dying trees in already fire-prone forests do not increase the wildfire threat. In reality, fire agencies and fire scientists are consistently describing the dead tree situation as an unnatural, extreme fire threat.

One key factor in the behavior of any wildfire is fuel moisture. Live, green trees – even in the hottest, driest time of summer – still contain moisture in their needles and branches that reduces fire intensity if the green trees are burned by a fire. In contrast, the tens of millions of trees that have already died from bark beetles add up to an unprecedented amount of bone-dry fuel. The highly flammable branches and tops of the dead pines, firs and cedars produce a perfect wick for flames to flare up into the crowns of adjacent dead and live trees. In addition, many of the dead trees that died during the last two years of the drought have dropped broken tops and branches that further add to the depth and the jumbled layers of flammable fuels on the forest floor.

In direct opposition to what Hanson’s editorial claimed, there is a significant threat to public and private forests of the Sierra Nevada due to the tens of millions of trees that have already died. There is no question that hot weather and windy conditions can create ideal conditions for high severity wildfires even when fuels are mostly green vegetation. But add in dead fuels to those same extreme conditions, and the basics of fire behavior will always result in an even higher degree of incineration and severity of a fire’s effects.

Hanson’s opinion piece reflected his long-standing opposition to any commercial logging on national forest lands. In contrast to that rigid view, the environmental organizations that serve as members of the Yosemite Stanislaus Solutions collaborative group strongly support more science-based thinning logging and salvage removal of a portion of trees killed by fire and insects.

With limited staff and resources, the U.S. Forest Service will only be capable of planning and implementing the removal of a small fraction of dead trees compared to the enormity of the conifer die-off. To suggest that leaving every dead tree makes sense defies any logic when even prior to the bark beetles, the drought and wildfires already created unnaturally high levels of dead trees and wildfire risk. Balanced collaborative groups such as YSS – made up of environmental organizations, industry and business interests, rural politicians and water agencies – strongly support the strategic removal of large numbers of the dead trees now posing so much risk across our iconic Sierra Nevada ecosystem.

Nathan Graveline is a wildlife biologist; Chris Trott is a bioenergy consultant; and John Buckley is executive director of the Central Sierra Environmental Resource Center.