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Many coastal forests stretching from central California to southwest Oregon are threatened or have been impacted by the invasive forest pathogen Phytophthora ramorum, cause of sudden oak death. We analyzed a set of stand-level forest treatments aimed at preventing or mitigating disease impacts on stand composition, biomass, and fuels, using a before-after-control-intervention experiment with a revaluation after five years. We compared the effects of restorative management in invaded stands to preventative treatments in uninvaded forests. The restorative treatments contrasted two approaches to mastication, hand-crew thinning, and thinning with pile burning with untreated controls (N=30) while the preventative treatments were limited to hand-crew thinning (N=10). Half of the restoration treatments had basal sprouts removed two- and four-years after treatment. All treatments significantly reduced stand density and increased average tree size without significantly decreasing total basal area both immediately and five years after treatments. Preventative treatments also significantly increased dominance of timber species not susceptible to P. ramorum. Follow-up basal sprout removal in the restoration experiment appears to maintain treatment benefits to average tree size and may be associated with small decreases in stand density five years after initial treatment. Our study demonstrates that for at least five years, a range of common stand management practices can improve forests threatened or impacted by sudden oak death. 

Purpose of Review I aim to contextualize wildfire-disease interactions with the goal of building a better understanding of where these may be of ecological importance and problems for sustainable forest management. Recent Findings While wildfire-disease interactions have been documented, they are not well represented in the ecological literature, probably because they require considerable effort or serendipity to rigorously quantify. Examples of disease-fire interactions are relatively limited and tend to be clearer in systems where fire and disease are management problems. The most resolved systems include Phytophthora pathogens although wildfire-disease interactions are not limited to these pathogens. Documented interactions encompass a range of effects which include the magnification of problems associated with each disturbance. Wildfire-disease interactions are also likely to shape basic ecological function in systems where both wildfire and disease are common but not necessarily critical management problems. Climate change has altered the fundamental controls on both fire and disease suggesting it will also alter the magnitude and likelihood (occurrence or detection) of disease-fire interactions. Summary I present a framework for linking wildfire-disease interactions and highlight the importance of host community/fuels structure on linking and mediating these interactions. I provide a series of examples where understanding interactive effects, interfacing with climate change, and the magnitude of changes to wildfire and disease intensification are of practical value and/or advance basic ecological knowledge. While much remains to be understood about these interactions, I make the argument that, in some cases, management can address both problems simultaneously.