Evidence-based Review of Seeding in Post-fire Rehabilitation and Native Plant Market Feasibility

A changing climate and fire regime shifts in the western United States have led to an increase in revegetation activities, in particular post-wildfire rehabilitation and the need for locally-adapted plant materials. Broadcast seeding is one of the most widely used post-wildfire emergency response treatments to minimize soil erosion, promote plant community recovery, and reduce non-native species invasions. However, these treatments can have negative ecological effects, due in part to the continued use of non-native species, although the use of native species has increased. We undertook an evidence-based systematic review to examine post-fire seeding treatments� effectiveness and effects on soils and plant communities in forests of the western U.S. Out of the 27 studies providing evidence regarding post-fire seeding effects on soil erosion, 33% of the studies showed seeding to be effective, an equal percentage of studies (26% each) showed minimal effectiveness or ineffectiveness, and 15% showed no difference in effectiveness of seeding in minimizing soil erosion. However, based on quality of evidence criteria, only one of 12 studies reported in the two highest quality categories qualified seeding effectiveness for soil erosion. Seventy-eight percent of study sites in publications evaluating soil erosion showed that seeding provides no additional benefit in reducing erosion relative to unseeded controls. Studies consistently showed that seeding reduced native species cover (62%) and/or suppressed recovery of native plants (60%), although long-term data on these effects are limited. Seeding was effective 3 in reducing non-native species invasions 54% of the time; however, of those treatments, 83% introduced additional negative impacts on native communities by seeding with non-native species. Post-fire seeding is costly and the scientific literature and management documentation show that it does little to protect soil and promote plant recovery in the short-term and may introduce potentially negative effects with long-term ecological consequences. Through a literature search, interviews and site visits, we identified existing native plant markets to use as models to assess the feasibility of a native plant market in the southern Colorado Plateau. We used web-based surveys to identify critical native plant material needs and concerns. Survey results indicate that management policy strongly drives decisions regarding the use and purchase of native plant materials. From a demand perspective, lack of availability and high cost of native plant materials has kept purchasing minimal, despite policy changes favoring the use of natives. For suppliers, further development of native plant materials is limited by inconsistent and unreliable demand and lack of production knowledge. The knowledge and tools necessary to initiate a native plant materials market are available. However, communication among producers, land managers, buyers, and researchers, as well as partnerships with local growers, appear to be vital to initiating a functional market