Cone Fire Summary
The severity and extent of wildfires in recent years have increased public awareness of the widespread fuels problem throughout much of the western United States. The 2002 and 2003 fire seasons served to accentuate the magnitude of the fuels problem in the minds of many. Yet, trends of increasing dead and live biomass (fuel) have been noted for many years. The increasing accumulations of fuels have been attributed to the altering of fire regimes by several factors, most notably nearly a century of attempted fire exclusion by various land management agencies. Both the Legislative and Executive branches of the Federal Government have responded by directing land management agencies to greatly expand fuel treatment programs including the recent Healthy Forests Restoration Act. While little information exists on the effectiveness of fuel treatments for reducing the severity of wildfires, even less information exists from wildfires that have burned into existing research projects designed to study effects of manipulating stand structure and other fuel treatments. Additionally, few treated sites have collected data prior to being burned in a wildfire to allow for more than anecdotal description of the affect of fuels treatment on subsequent fire effects.
In September of 2002, during north wind conditions with very low humidity, the Cone Fire burned over 2000 acres, mostly on the Blacks Mountain Experimental Forest where a large project was underway to study ecological responses to contrasting stand structures. Treatments implemented before the fire included mechanical thinning with and without slash reduction through prescribed fire. All treatments were accomplished less than 6 years prior to the wildfire occurrence. The historic fire regime of this ecosystem was of the frequent/low-moderate severity type of interior ponderosa pine in the southern Cascade Range of northern California.
Initial observations indicate that treated stands experienced lower fire severity than untreated stands. Additionally, stands thinned without follow-up prescribed fire appear to have experienced higher fire severity than those where thinning was followed by prescribed fire. However, in the case of both treatments the fire dropped quickly out of the crowns to become either a surface fire or die out upon entering the treated areas. The rapidity of apparent change from a high-intensity crown fire to a much lower-intensity surface fire may have significant implications for management of wildland/urban interface zones as well as wildlands in general.
Though we are describing preliminary results here, clearly differing levels of treatments were associated with dramatic differences in levels of fire-related tree mortality. These are only the initial findings and many additional research projects have been developed from the Cone Fire incident (Refer below for the list of projects). From this research we hope to gain a better understanding of the pre and post issues surrounding wildfire on this forest type.