Spork THP Comments
November 15, 2025
Forest Practice Program Manager
CAL FIRE
1234 East Shaw Avenue
Fresno, California 93710
To whom it may concern:
The following comments concern the Wildfire Risk and Hazard regarding the 4-25-00168-CAL, Spork Timber Harvest Plan (THP).
Spork THP consists of a 986-acre timber harvest which includes 676 acres of clearcutting and 251 acres of fuel breaks. The post-harvest stocking for clearcut lands consists of and even-aged management with a 125-point count within 5-year post-harvest. The harvest area is located in an Easterly direction approximately distance of about five miles away between Arnold and Wilseyville.
Forest Fuel breaks
Section IV, pages 163 and 254 describes the THP as being in a Very High Fire Hazard Severity Zone. you further state on page 254 “… that extreme weather and wind events … can defy the more traditional understanding of predicted fire behavior and create high risk for wildfires in most areas of California on a potentially large scale. “
It is those extreme weather and wind events that have become the new normal caused by climate change. This climate change effect on our forests and subsequent mega fires, which are now all too common, have become the new normal. In this new normal, construction of fuel breaks can have a reverse effect on wildfires. In as much, there’s a strong argument that fuel breaks dry out the soil and can create a wind tunnel effect whereby it would fan a fire’s growth rather than retard it.
Alexandra Syphard, adjunct professor at San Diego State who studied the impacts of fuel breaks said, “When you have really high wind conditions, hot and dry, that are coming off mountains, fires are very difficult to control. There’s a very good change that the fire is going to continue through the fire break.”
This climate change effect can be best shown by the impact and burn area caused by the 2021 Caldor Fire. Satellite mapping of the Caldor Fire shows that even with extensive fuel reduction and fuel breaks in the burned areas over the last several years had minimal effect on slowing the growth and intensity of that fire.
Examples that CAL FIRE used in the past to justify the extensive network of fuel breaks have been to protect forest communities such as the town of Shaver Lake in the central Sierra 2020 Creek fire. However, scientific studies have shown that the only effective way to protect homes from fire is home-hardening and defensible space pruning within 100 to 200 feet of homes or less. The following studies question the effectiveness of fuel breaks.
Cohen, J.D. (U.S. Forest Service). 2000. Preventing disaster: home ignitability in the wild land urban interface. Journal of Forestry 98: 15-21.
The only relevant zone to protect homes from wildland fire is within approximately 135 feet or less from each home—not out in wildland forests.
Gibbons P, van Bommel L, Gill MA, Cary GJ, Driscoll DA, Bradstock RA, Knight E, Moritz MA, Stephens SL, Lindenmayer DB (2012) Land management practices associated with house loss in wildfires. PLoS ONE 7: Article e29212.
Defensible space pruning within less than 130 feet from homes was effective at protecting homes from wildfires, while vegetation management in remote wildlands was not. A modest additional benefit for home safety was provided by prescribed burning less than 500 meters (less than 1641 feet) from homes.
Syphard, A.D., T.J. Brennan, and J.E. Keeley. 2014. The role of defensible space for residential structure protection during wildfires. Intl. J. Wildland Fire 23: 1165-1175.
Vegetation management and removal beyond approximately 100 feet from homes provides no additional benefit in terms of protecting homes from wildfires.
Bryant Baker, Conservation Director Los Padres Forest Watch has found the 25 highest-profile firebreaks created in 2020, only about 2 percent of those 90,000 acres cleared by fire crew every encountered a wildfire. In today’s fire climate Baker states, “The fires just completely overrun the fuel breaks, especially under extreme, windy conditions. These extreme fires are the ones we need to be concerned about and the ones that are doing most of the damage.”
Fuels Treatments
On page 255, three published scientific studies were referenced regarding forest fuel reduction treatments and their effects on high severity fires. All three of these studies concluded that treated managed forests reduced the fire severity and tree mortality. A problem with many of these studies is that they can be biased and usually are funded almost entirely by the timber industry. For example, these studies many times don’t take into account for the trees killed and removed by the thinning itself. There are many other scientific studies that have concluded the opposite true not financed by the timber industry. Below listed are the findings of some of those other independent scientific studies.
“The most fire suppressed forest, which tend to be the densest, burn mostly at low or moderate intensity when wildland fires occur. This finding was true for even those forests that had not burnt in over a century. These studies concluded the primary determinate on how a fire burns were climate factors and not forest density.”
Jay D Miller et al., “Trends and Causes of Severity, Size, and Number of Fires in Northwestern California, Ecological Application 22 (2012): 184-203; Dennis C. Odion et Al., “Patterns of Fire Severity and Forest Condition in the Klamath Mountains” Conservation Biology 18 (2004)
“Thinned forests often burn more intensely in wildland fires. This intensity is because thinning reduces the windbreak effect of denser forests. Winds are then allowed to sweep through a forest more rapidly, while also reducing the shade of the forest canopy, thus creating hotter and drier conditions.“
Miguel G. Cruz, Martin E. Alexander and Jetmer E. Dam, “Using Modeled Surface and Crown Fire Behavior Characteristics to Evaluate Fuel Treatment Effectiveness: A Caution.”, Forest Science 60 (2014): 1000-1004; Miguel G. Cruz, Martin E. Alexander, and Paulo A. Fernandes, “Development of a Model System to Predict Wildlife Behavior in Pine Plantations.” Austranlian Foresty 71(2008)
Conclusion
Given our above concerns regarding the effectiveness of a fuel break and fire treatments, CAL FIRE should reevaluate their criteria used to determine the size, location, and cost analysis of the effectiveness of these firebreaks. Given the possible harmful effects caused by thinning and firebreaks (i.e., increases in fire spreading winds, drying of exposed fire break areas) an analysis of these thinning impacts should be included in this THP.
Thank you for your consideration,
Perry Metzger, President
Ebbetts Pass Forest Watch
Copies furnished:
Secretary Wade Crowfoot, California Natural Resources Agency
