The 12-site National Fire and Fire Surrogate study (FFS) was a multivariate experiment that evaluated ecological consequences of alternative fuel-reduction treatments in seasonally dry forests of the US. Each site was a replicated experiment with a common design that compared an un-manipulated control, prescribed fire, mechanical and mechanical + fire treatments. Variables within the vegetation, fuelbed, forest floor and soil, bark beetles, tree diseases and wildlife were measured in 10-ha stands, and ecological response was compared among treatments at the site level, and across sites, to better understand the influence of differential site conditions. For most sites, treated stands were predicted to be more resilient to wildfire if it occurred shortly after treatment, but for most ecological variables, short-term response to treatments was subtle and transient. Strong site-specificity was observed in the response of most ecosystem variables, suggesting that practitioners employ adaptive management at the local scale. Because ecosystem components were tightly linked, adaptive management would need to include monitoring of a carefully chosen set of key variables. Mechanical treatments did not serve as surrogates for fire for most variables, suggesting that fire be maintained whenever possible. Restoration to pre-settlement conditions will require repeated treatments over time, with eastern forests requiring more frequent applications.

Forest fuel reduction treatments are increasingly used by managers to reduce the risk of high-severity wildfire and to manage changes in the ecological function of forests. However, comparative ecological effects of the various types of treatments are poorly understood. We examined short-term patterns in small-mammal responses to mechanical thinning, prescribed-fire, and mechanical thinning/prescribed-fire combination treatments at eight different study areas across the United States as a part of the National Fire and Fire Surrogate (FFS) Project. Research questions included: (1) do treatments differ in their effect on small mammal densities and biomass? and (2) are effects of treatments consistent across study areas? We modeled taxa-specific densities and total small-mammal biomass as functions of treatment types and study area effects and ranked models based on an information-theoretic model selection criterion. Small-mammal taxa examined, including deer mice (Peromyscus maniculatus), yellow-pine chipmunks (Tamias amoenus), and golden-mantled ground squirrels (Spermophilus lateralis), as well as all Peromyscus and Tamias species, had top-ranked models with responses varying both by treatment type and study area. In each of these cases, the top-ranked model carried between 69% and 99% of the total weight in the model set, indicating strong support for the top-ranked models. However, the top-ranked model of total small-mammal biomass was a model with biomass varying only with treatment (i.e., treated vs. untreated), not by treatment type or study area; again, this model had strong support, with 75% of the total model weight. Individual species and taxa appear to have variable responses to fuel reduction treatment types in different areas; however, total small-mammal biomass appears generally to increase after any type of fuel reduction. These results suggest that there is substantial variability in taxa-specific responses to treatments and indicate that adaptive management policies may be necessary when applying fuel reduction treatments in areas where management of small-mammal populations is of interest. Adaptive management can be used by managers who are conducting fuel reduction treatments to reduce uncertainty as to which treatments are locally optimal for meeting objectives for the management of small-mammal populations.

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We investigated the relationship between foraging woodpeckers and the decomposition of ponderosa pine (Pinus ponderosa) snags in the central and southern Cascades of Oregon and northern California. Our main objectives were (1) to compare the relative sapwood density of 4-year-old pine snags receiving varying levels of woodpecker foraging; and (2) to determine if woodpeckers were carriers of wood-inhabiting fungi. Snags used as foraging sites by woodpeckers had lower wood densities than snags that did not exhibit foraging sign. Additionally, wood-inhabiting fungi were recovered in significantly greater frequencies from the bills of woodpeckers than a comparison of non-cavity-nesting species. These results suggest that woodpeckers may contribute to the mechanical degradation of wood through foraging activities and the dispersal of a collection of fungi that likely participate in the process of decay for ponderosa pine snags. The complexity of these ecological interactions should be considered when planning snag management in coniferous forests. El Papel de Forrajeo de los Carpinteros en la Descomposición de Tocones de Pinus ponderosa Resumen. Investigamos la relación entre las actividades de forrajeo de los carpinteros y la descomposición de tocones de Pinus ponderosa en el centro y sur de las Cascades de Oregon y el norte de California. Nuestros objetivos principales fueron (1) comparar la densidad relativa de la albura de tocones de pino de 4 años de edad afectados por distintos niveles de forrajeo por parte de los carpinteros; y (2) determinar si los carpinteros transportaron hongos de la madera. Los tocones usados como sitios de forrajeo por los carpinteros tuvieron densidades de madera menores que los tocones que no presentaron señales de forrajeo. Adicionalmente, los hongos de la madera fueron encontrados con mayor frecuencia en los picos de los carpinteros que en especies que no nidifican en cavidades. Estos resultados sugieren que los carpinteros pueden contribuir a la degradación mecánica de la madera mediante las actividades de forrajeo y la dispersión de una variedad de hongos que probablemente participan en el proceso de descomposición de los tocones de P. ponderosa. La complejidad de estas interacciones ecológicas debería ser considerada a la hora de planear el manejo de los tocones en los bosques de coníferas.

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