Feasibility evaluation of BLM fire rehabilitation data from the Intermountain West for potential chronosequence studies

Background/Question/Methods The Bureau of Land Management (BLM) and other Department of the Interior bureaus have recently invested heavily in seeding vegetation for emergency stabilization and rehabilitation (ESR) of non-forested arid lands. These projects are typically intended to reduce post-fire dominance of non-native annual grasses, minimize probability of recurrent fire, and ultimately produce desirable vegetation characteristics (e.g., ability to recover following disturbance (resilience), resistance to invasive species, and capacity to support a diverse flora and fauna). While projects historically have been monitored to varying extents, land managers lack scientific evidence to verify whether seeding arid and semiarid lands achieves desired objectives. Given the amount of resources dedicated to post-fire seeding projects, a synthesis of information determining the factors that result in successful treatments is critically needed. The goal of this feasibility study was to evaluate historic ESR records from the BLM in the Intermountain West to determine the types and extent of ESR data that would be available over time for a field-based chronosequence assessment of fire rehabilitation during the past 30 years.

Results/Conclusions We collected data from 703 post-fire seeding projects with 1,193 individual seeding treatments at nine BLM field offices in four states (Oregon, Idaho, Nevada, and Utah). Projects sampled were implemented between 1981 and 2007 and included planning documentation (89.6% of seeding treatments examined) or post-seeding reporting (65.7%), but effectiveness monitoring data was less common (34.5%). Our preliminary findings identified 464 projects (39.0%) that would be most preferable for a field chronosequence study (i.e., projects with planning documents, seed lists, and some effectiveness monitoring). In this potential sampling population, there were 259 aerial seeding treatments and 205 ground seeding treatments, with 18, 41, and 200 aerial and 41, 45, and 119 ground seeding projects in the 1980-89, 1990-99, and 2000-07 periods, respectively. Although these 464 projects have the most extensive data available, ESR seedings without monitoring data (28, 154, and 32 aerial and 70, 175, and 31 ground seeding treatments in the 1980-89, 1990-99, and 2000-07 periods, respectively) could be added, if necessary, to the potential sampling group in order to design a spatially and temporally balanced chronosequence study. Our findings indicate that an evaluation of BLM emergency fire rehabilitation projects within the Intermountain West using a chronosequence approach may be possible and would likely provide relevant ecological data for suggesting improvements in future post-fire land management decisions.