@article{cobb_haas_kruskamp_dillon_swiecki_rizzo_frankel_meentemeyer_2020, title={The Magnitude of Regional-Scale Tree Mortality Caused by the Invasive PathogenPhytophthora ramorum}, volume={8}, ISSN={["2328-4277"]}, url={https://doi.org/10.1029/2020EF001500}, DOI={10.1029/2020EF001500}, abstractNote={Forest pathogens are important drivers of tree mortality across the globe, but it is exceptionally challenging to gather and build unbiased quantitative models of their impacts. Here we harness the rare data set matching the spatial scale of pathogen invasion, host, and disease heterogeneity to estimate infection and mortality for the four most susceptible host species of Phytophthora ramorum, an invasive pathogen that drives the most important biological cause of tree mortality in a broad geographic region of coastal California and southwest Oregon. As of 2012, the most current field survey year, we estimate 17.5 (±4.6, 95% CI [confidence interval]) million tanoak (Notholithocarpus densiflorus) stems were pathogen killed with an additional 71 (±21.5) million infected. We estimated 9.0 million (±2.2) coast live oak (Quercus agrifolia) and 1.7 million (±0.5) California black oak (Quercus kelloggii) stems are disease impacted (mortality and infection combined). Lastly, our estimates suggest infection in 95.2 million (±8.6) California bay laurel (Umbellularia californica), which does not suffer mortality from infection and represents a critical source of continued spread. Prevalent infection as of 2012 suggests the cumulative number of disease‐killed stems likely increased from 20.8 to 42.8 million between 2012 and 2019 for all species. While these impacts are substantial, most host populations occur in a yet to be invaded region of northern California indicating that the disease will intensify in the coming decades.}, number={7}, journal={EARTHS FUTURE}, author={Cobb, Richard C. and Haas, Sarah E. and Kruskamp, Nicholas and Dillon, Whalen W. and Swiecki, Tedmund J. and Rizzo, David M. and Frankel, Susan J. and Meentemeyer, Ross K.}, year={2020}, month={Jul} }
 @article{haas_cushman_dillon_rank_rizzo_meentemeyer_2016, title={Effects of individual, community, and landscape drivers on the dynamics of a wildland forest epidemic}, volume={97}, DOI={10.1890/15-0767}, abstractNote={The challenges posed by observing host–pathogen–environment interactions across large geographic extents and over meaningful time scales limit our ability to understand and manage wildland epidemics. We conducted a landscape-scale, longitudinal study designed to analyze the dynamics of sudden oak death (an emerging forest disease caused by Phytophthora ramorum) across hierarchical levels of ecological interactions, from individual hosts up to the community and across the broader landscape. From 2004 to 2011, we annually assessed disease status of 732 coast live oak, 271 black oak, and 122 canyon live oak trees in 202 plots across a 275-km2 landscape in central California. The number of infected oak stems steadily increased during the eight-year study period. A survival analysis modeling framework was used to examine which level of ecological heterogeneity best predicted infection risk of susceptible oak species, considering variability at the level of individuals (species identity, stem size), the community (host density, inoculum load, and species richness), and the landscape (seasonal climate variability, habitat connectivity, and topographic gradients). After accounting for unobserved risk shared among oaks in the same plot, survival models incorporating heterogeneity across all three levels better predicted oak infection than did models focusing on only one level. We show that larger oak trees (especially coast live oak) were more susceptible, and that interannual variability in inoculum production by the highly infectious reservoir host, California bay laurel, more strongly influenced disease risk than simply the density of this important host. Concurrently, warmer and wetter rainy-season conditions in consecutive years intensified infection risk, presumably by creating a longer period of inoculum build-up and increased probability of pathogen spillover from bay laurel to oaks. Despite the presence of many alternate host species, we found evidence of pathogen dilution, where less competent hosts in species-rich communities reduce pathogen transmission and overall risk of oak infection. These results identify key parameters driving the dynamics of emerging infectious disease in California woodlands, while demonstrating how multiple levels of ecological heterogeneity jointly determine epidemic trajectories in wildland settings.}, number={3}, journal={Ecology}, author={Haas, S. E. and Cushman, J. H. and Dillon, W. W. and Rank, N. E. and Rizzo, D. M. and Meentemeyer, Ross K.}, year={2016}, pages={649–660} }
 @article{dillon_haas_rizzo_meentemeyer_2014, title={Perspectives of spatial scale in a wildland forest epidemic}, volume={138}, ISSN={["1573-8469"]}, DOI={10.1007/s10658-013-0376-3}, number={3}, journal={EUROPEAN JOURNAL OF PLANT PATHOLOGY}, author={Dillon, Whalen W. and Haas, Sarah E. and Rizzo, David M. and Meentemeyer, Ross K.}, year={2014}, month={Mar}, pages={449–465} }