Sheep Fire Ecological Resources Post-Fire Recovery Plan

Sheep Fire Ecological Resources Post-Fire Recovery Plan Report (pdf file)


Amy D. Forman, Jackie R. Hafla, Sue J. Vilord, Jeremy P. Shive, Kristin N. Kaser, Quinn R. Shurtliff, Kurt T. Edwards, and Bryan F. Bybee

January 2020

A Wildland Fire Management Environmental Assessment was completed for the Idaho National Laboratory (INL) in 2003 in response to the increasing frequency of wildland fires. One requirement of the Assessment was for INL to establish a Wildland Fire Management Committee and one responsibility of the Committee is to determine when the development of a post-fire recovery plan for fires larger than 100 ac (40 ha) is warranted. Following the 2019 Sheep Fire, INL’s Wildland Fire Management Committee determined that a post-fire recovery plan should be developed to address impacts of fire suppression activities and the potential effects of the fire on native species recovery and associated wildlife habitat within the burned area. Committee members expressed an interest in a plan where implementation is phased over five years and in a plan that is flexible, where specific actions can be implemented individually depending on specific resource concerns and funding availability.

The lightning-caused Sheep Fire started on July 22, 2019 in a remote region of the INL Site east of T-4 and south of T-9. The INL Site Fire Department and Bureau of Land Management responded under a unified command employing multiple fire suppression strategies. At the time of initial response, the fire was approximately 2,000 ac (809 ha) in size but quadrupled overnight and moved towards the southwest. Redflag and thunderstorm warnings were posted on July 23 and 24 as winds increased and relative humidity remained low, and the fire expanded to over 80,000 ac (32,375 ha). Minimal fire activity was reported on July 25, and the Sheep Fire was 100% contained by the afternoon of July 26. The initial Sheep Fire boundary was created by the Bureau of Land Management and estimated the burned area to be approximately 112,107 ac (45,368 ha). The Environmental Surveillance, Education and Research Program later used high resolution satellite imagery collected after the fire to delineate the Sheep Fire burned area and, for post-fire recovery planning purposes, reduced the burned area estimate to approximately 99,839 ac (40,403 ha).

The fire impacted a variety of ecological resources including 21 different soils types, nine vegetation classes, and numerous wildlife species, including greater sage-grouse, which is designated as Species of Greatest Conservation Need by the State of Idaho. This plan discusses the potential risks of the Sheep Fire to ecological resources and challenges to the natural recovery of those resources. The Wildland Fire Management Committee can use this information to evaluate and prioritize specific fire recovery actions. Treatment options for improving post-fire recovery are included as well as the steps necessary to implement those options.

Natural resource recovery issues were organized into four objectives. Those objectives are listed here, along with and the information that should be considered for developing treatment actions:
1. Soil stabilization for erosion and weed control immediately post-fire,

  • Characterize the amount/severity of direct soil disturbance and prioritize restoration activities
  • Recontour containment lines and seed direct soil disturbance with a native grass mix
  • Sign and/or barricade the containment lines to prevent traffic
  • Monitor and spray containment lines for weeds
  • Assess any soil disturbance associated with powerline repair and restore accordingly

2. Cheatgrass and noxious weed control within the larger burned area,

  • Identify areas that may benefit from cheatgrass treatment
  • Apply a pre-emergent herbicide to selected areas at greatest risk for cheatgrass dominance
  • Conduct a weed inventory and treat noxious weeds

3. Native herbaceous recovery, and

  • Rest the allotment portion of the burn area for at least two growing seasons
  • Identify locations of potentially poor native herbaceous recovery
  • Plant native perennial grasses in areas with poor native recovery

4. Sagebrush habitat restoration.

  • Prioritize areas that would benefit from planting sagebrush
  • Evaluate planting options
  • Coordinate a local seed collection effort
  • Locate available seed that may be appropriate for use on the INL Site
  • Aerially plant sagebrush seed in high priority areas
  • Plant sagebrush seedlings strategically to address specific areas where accelerated recovery would be beneficial to habitat recovery

Based on stakeholder input, the U.S. Department of Energy decided to pursue aerial sagebrush seeding on portions on the Sheep Fire during the winter of 2019/2020. The Environmental Surveillance, Education, and Research Program provided logistical support for this effort and the U.S. Fish and Wildlife Service, the Bureau of Land Management, and the Idaho Office of Species Conservation helped with seed acquisition. Two areas within the footprint of the Sheep Fire were proposed for aerial sagebrush seeding including a 12,521 ac (5,067 ha) area within the Sage-grouse Conservation Area and a second area, which is 11,828 ac (4,787 ha) and is outside of, but adjacent to the Sage-grouse Conservation Area. Habitat for sagebrush obligates would benefit from aerial seeding in both areas, and recent telemetry data from other agencies suggest they are important wintering habitat for greater sage-grouse.

To identify areas that may need to be treated and to evaluate the outcome of any treatments that are implemented, an effective monitoring plan should be designed and implemented. Effective monitoring plans are those that establish a process to collect, analyze, and use data to track the status of the natural resources of interest and interpret the effectiveness of any implemented actions or treatments against benchmarks developed to evaluate success. Appropriate monitoring methods may include remote sensing using satellite or airborne-based imagery and field-based rapid assessment techniques. Ideally, monitoring results will be used within an adaptive management framework so that previous results inform future decisions.