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.

中文翻译：

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入侵病原疫霉引起的区域范围树木死亡率的幅度

森林病原体是全球树木死亡率的重要驱动因素，但收集和建立其影响的无偏定量模型异常地具有挑战性。在这里，我们利用与病原体入侵，寄主和疾病异质性的空间尺度相匹配的稀有数据集，来估计四种最易感寄主疫霉菌（Phytophthora ramorum）的感染和死亡率，该病原菌是导致树木死亡的最重要生物学原因加利福尼亚沿海和俄勒冈州西南部的广阔地理区域。截至2012年，这是最新的实地调查年，我们估计有17.5（±4.6，95％CI [置信区间]）百万塔纳克（Notholithocarpus densiflorus）茎被病原体杀死，另有71（±21.5）百万感染。我们估计9.0百万（±2.2）沿海活橡（Quercus agrifolia）和170万（±0.5）加州黑橡（Quercus kelloggii）茎受到疾病影响（死亡率和感染率合计）。最后，我们的估计表明感染了9520万（±8.6）加利福尼亚湾月桂（Umbellularia californica），不会因感染而致死，是持续传播的重要来源。截至2012年，流行感染表明，所有物种在2012年至2019年期间，疾病杀死的茎的累积数量可能从20.8增至4280万。尽管这些影响是巨大的，但大多数寄主种群发生在北加州尚未被入侵的地区，这表明该病将在未来几十年内加剧。