Channel response to low-elevation desert fire: The King Valley Fire of 2005

In late September to early October 2005, a fire swept north from the Yuma Proving Grounds and into the Kofa National Wildlife Refuge (NWR), traveling mainly along desert wash systems and low-relief alluvial fans. This fire burned 9,975 ha, moving through xeroriparian systems in washes as well as low-elevation desert ecosystems in King Valley, a major area of designated wilderness in the southern part of the Kofa NWR. Using satellite imagery, we determined that 9,255 ha of the Kofa NWR in King Valley burned. The fine-fuel loading for the fire was mostly a native forb (Plantago insularis), and the desert environment that was burned was mostly low-cover creosote bush (Larrea tridentata) scrub with scattered palo verde (Cercidium microphyllum). The wash environments had significant tree cover, including ironwood (Olneya tesota), blue palo verde (Cercidium floridum), desert willow (Chilopsis linearis), and/or smoke tree (Psorothamnus spinosa). This report presents monitoring data collected in June 2006 and January-February 2007 on the effects of this fire on channel morphology in King Valley.