Single Publication

The Soil Burn Severity map is now complete for the Cody Fire, located outside of Oracle, Arizona, in the Santa Catalina Ranger District, Coronado National Forest.

Soil Burn Severity (Color coordinated on the map)
Soil Burn Severity is a measure of the fire’s effects on the ground surface and soil condition. This map identifies the fire-induced changes in soil and ground surface properties that may affect infiltration, runoff, and erosion potential. The Burned Area Emergency Response (BAER) Team uses this map to identify areas of unacceptable risk to a critical value and where mitigating treatments may be most effective on Forest System land. This product is appropriate for wildland landscapes and does not represent fire effects in developed areas.

Hydrological Models

The Burned Area Emergency Response team has begun running hydrological models to estimate increases in peakflows from pre to postfire conditions. Using the fire perimeter overlay, the Smelter Wash subwatershed was identified as the location of most of the burn. This watershed drains to the east of the town of Oracle and north of the town of San Manuel. The two main drainages within the Smelter Wash subwatershed that drain off the burn are the Smelter and Ray Spring washes.

The Tucson Wash subwatershed, which has a drainage leading towards the town of Oracle, was not impacted by the Cody Fire and is expected to have no discernable impacts from the Cedar Fire.

Community Resources
The Natural Resources Conservation Service (NRCS) has programs to mitigate post-fire impacts. Entities, such as counties, cities, and tribes, may be eligible for Emergency Watershed Protection (EWP) to address watershed scale projects while farmers and ranchers may be eligible for the Environmental Quality Incentives Program (EQIP) for on-farm impacts. For information, please contact the acting supervisor for the Tucson Field Office of NRCS, Emilio Carrillo (emilio.carrillo@usda.gov or 520-305-5147).

Burn Severity Indicators Definitions
High soil burn severity (Cody Fire 0 acres) – Most or all of the pre-fire ground cover and surface organic matter (litter, duff, and fine roots) is generally consumed, and charring may be visible on larger roots. Soil is often gray, orange, or reddish at the ground surface where large or dense fuels were concentrated and consumed. Soil structure is often altered and less stable at the surface.

Moderate soil burn severity (Cody Fire 298 acres) – Up to 80 percent of the pre-fire ground cover may be consumed, but generally not all of it is. There may be potential for the recruitment of effective ground cover from scorched needles or leaves remaining in the canopy that will soon fall to the ground. Soil structure is generally unchanged. 

Low soil burn severity (Cody Fire 893 acres) – The ground surface, including any exposed mineral soil, may appear brown or black (lightly charred), and surface organic layers are not completely consumed. The canopy and understory vegetation will likely appear “green.”

Very Low soil burn severity or Unburned (Cody Fire 29 acres) – Little to no burn expected within these areas, except in small patches, or where fuels were sparce. Canopy and ground litter are almost completely intact. Little to no vegetation mortality expected.

For additional information including photo examples of soil severity see the Field Guide for Mapping Post-Fire Soil Burn Severity at: http://www.fs.usda.gov/rm/pubs/rmrs_gtr243.pdf

Spatial data for the soil burn severity can be obtained by emailing the Coronado National Forest atmailroom_R3_Coronado@usda.gov.