I have broad interests in forestry and ecology, and I'm especially fond of the great diversity of habitats one can find in the Pacific Northwest. I've tried to distill some of my past and current work into four broad categories.
Dry forest restoration
Historically, many dry coniferous forests burned relatively frequently, often at low to mixed severity. However, past land management, combined with a warmer and drier climate, has increased the probability of severe (stand-replacing) wildfire in many of these forests. Similarly, increasing stand density has contributed to increased susceptibility to insects, diseases, and drought. I study the effects and efficacy of the primary options available to land managers to reduce these hazards: mechanical thinning and prescribed fire. I'm interested in studying a wide variety of effects, especially as this enables understanding trade-offs and "win-win scenarios. Specifically I've examined, effects on fuels and fire hazard, snag retention/development (as key habitat structures), residual tree growth, tree regeneration, understory vegetation cover and diversity, and exotic species invasion.
Post-fire recovery
Inevitably linked with the above issue of increasing fire size and severity is a need to understand what happens after a fire, as it appears large servere fires are unlikely to totally go away in the near future, even with increased dry forest restoration efforts. Severe fires can have considerable economic and ecological consequences such as eliminating habitat (e.g., old growth forest) and increasing flooding and erosion hazards. However, severe fires can also increase other valued habitats (i.e., snags and diverse early seral vegetation). I study a variety of natural processes following wildfire to better understand variability in natural recovery and potential trade-offs that can be used to inform post-fire management to facilitate more desirable outcomes from a sociological and ecological perspective. For example, I've studied snag longevity and use by cavity nesters and how this varies over time for different tree sizes and species, as well as fuel accumulation dynamics as snags decay and fall (contributing re-burn potential). Similarly, I've examined natural regeneration dynamics, attempting to understanding limiting factors and why natural regeneration can vary so strongly from one site to another. I've also studies recovery of vegetation, a primary factor limiting erosion and flooding hazards after wildfires, including attempting to examine factors that may lead to fast (or slow) recovery and exotic invasion (or not).
Post-fire management
Strongly linked with post-fire recovery, I've investigated management effects on post-fire habitats. For example, I've studied how salvage logging can influence post-fire fuels and how this varies over longer time frames (up to 39 years). I've also investigated the effects of post-fire seeding, mulching and fertilization on vegetation community recovery including effects on exotic invasion and tree regeneration.
Silviculture effects on stand structure and habitat
Silviculture is a powerful tool that can be used to both produce wood products and modify forest structure and function. In addition to reducing fire hazard as described above, silviculture can be used to create suitable habitat for regeneration of desired species, create diverse early seral habitat, encourage growth of large trees, and increase within stand diversity. I study how various sivilcultural prescriptions affect stand development, including overstory and understory vegetation. Because many operational-scale sites are not homogeneous this often involves looking at the fine-scale within stand conditions and how this shapes development (e.g., microsite effects on seedling establishment). Similarly, no two sites have the exact same biophysical environment or site history, so I also look at how large-scale variation in conditions such as these could affect stand responses to silviculture, which has important implications for thinking about potential effects of a treatment at a new site.