James Youtz, US Forest Service, jayoutz@fs.fed.us (Presenter)
Patrick L. Jackson, US Forest Service, pljackson01@fs.fed.us
Tessa Nicolet, US Forest Service, tnicolet@fs.fed.us
Richard T. Reynolds, USDA Forest Service, rreynolds@fs.fed.us
Andrew J. Sánchez Meador, USDA Forest Service, andrew.sanchezmeador@gmail.com


The composition and structure of vegetation in frequent fire forests in the Southwest have significantly changed from historical, natural conditions (e.g., increased tree densities, reduced spatial structural heterogeneity, and changed food webs and trophic interactions). These changes are associated with increases in the number, size, and severity of wildfires, insect and disease episodes, altered species demographies, and reduced biodiversity, ecosystem function, resilience, and sustainability of frequent fire forests. Forest Service policy requires managers to address ecological restoration and to integrate restoration strategies into Forest Plans. We present desired forest conditions for restoring Southwestern frequent fire forests (ponderosa pine and dry mixed-conifer); the scientific basis is the documented natural range of variability and reference conditions of these forests. Key structural elements of the desired conditions are an uneven-aged forest mosaic comprised of tree groups, individual trees, grass-forb-shrub openings, snags, logs, woody debris, and the arrangement of these elements in space and time. The objective of the desired conditions is to provide a vision to inform management actions such that treatments may be developed to restore the spatiotemporal feedbacks between pattern and process in these forests. Desired conditions might only approximate natural structural and functional diversity within tree groups since it may not be operationally feasible to mimic natural processes that produced the structural reference conditions at the fine scale (i.e., tree-group level). Nonetheless, the ecological benefits of achieving the desired conditions at all scales far outweigh minor deviations from these fine-scale reference conditions.