Bioclimatic model-based predictions of potential distributions for four forest root disease pathogens under changing climates in western North America

Abstract

Root diseases are a major cause of conifer damage in forests of western North America. Two major root diseases in the region, which are caused by native pathogens, are laminated root rot (LRR) disease of Douglas-fir (Pseudotsuga menziesii) caused by Coniferiporia sulphurascens (Agne et al. 2018; Lockman and Kearns 2016; Thies and Sturrock, 1995), and black stain root disease (BSRD) caused by three fungal pathogens: Leptographium wageneri on single-leaf pinyon pine (Pinus monophylla) and pinyon pine (P. edulis), L. ponderosum on ponderosa pine (P. ponderosa) and Jeffrey pine (P. jeffreyi), and L. pseudotsugae on Douglas-fir (Choi et al. 2023).<br><br>As the climate changes, suitable climate spaces (potential distribution) for both hosts and pathogens will likely shift (e.g., Kim et al. 2021). Changes in climate that result in increased frequency/intensity of drought and severe heat are also likely to increase forest host stress and damage from root disease (Chmura et al. 2011; Murray and Leslie 2021; Kim et al. 2021). Management options are limited for forest root diseases; however, forest managers can use information about potential distributions of LRR and BSRD pathogens to address these root diseases. This information can be obtained by identifying geographic areas where hosts and pathogens are likely to co-occur based on climatic variables under contemporary and projected future climate scenarios. Establishing and monitoring potential LRR and BSRD risk maps that show potential distributions of pathogens and hosts under contemporary and projected future climates provides critical information to forest managers for minimizing future damage from both root diseases.

Citation

Kroese, Duncan R.; Choi, Daram; Shaw, David C.; Bennett, Patrick I.; Klopfenstein, Ned B.; Kim, Mee-Sook. 2025. Bioclimatic model-based predictions of potential distributions for four forest root disease pathogens under changing climates in western North America. In: Carson, Adam R., comp. Proceedings of the 69th Western International Forest Disease Work Conference; 9-13 September 2024; Santa Fe, New Mexico. Corvallis, OR: Oregon State University, Engineering Resources and Management, Swiss Needle Cast Cooperative. p. 64-67.