Aerial spore sampling to assess white pine blister rust risk in western white pine (Pinus monticola) and whitebark pine (P. albicaulis) stands at Priest River Experimental Forest in northern Idaho

Abstract

Cronartium ribicola is an invasive forest pathogen that causes white pine blister rust, which threatens the health and productivity of five-needled white pines including iconic species, such as western white pine (WWP; Pinus monticola) and whitebark pine (WBP; P. albicaulis) in western North America. The pathogen has invaded most of the natural ranges of WWP and WBP and has dramatically altered forest composition and structure across the landscape (Neuenschwander et al. 1999). In recent decades, efforts to increase resilience of forest landscapes have led to a renewed interest in restoring WWP as a component of mesic and early seral forest ecosystems in the Northern Rockies, where WWP is a keystone species (Chmura et al. 2011, Bollenbacher et al. 2014). The widespread distribution of C. ribicola presents a challenge to these restoration efforts, even with the increased use of blister rust-resistant planting stock. In higher elevation ecosystems, C. ribicola, fire, beetles, and climate change threaten the existence of WBP in its role as a foundational and keystone species (Tomback et al. 2016). However, a better understanding of the factors affecting the growth and development of C. ribicola and its infection processes is needed to guide both management and conservation efforts of WWP and WBP.

Citation

Bennett, Patrick I.; Reinhardt, Jason; Basham, Hannah; Mutchler, Nicole; Cleaver, Christy; Hanna, John W.; Klopfenstein, Ned B.; Stewart, Jane E. 2024. Aerial spore sampling to assess white pine blister rust risk in western white pine (Pinus monticola) and whitebark pine (P. albicaulis) stands at Priest River Experimental Forest in northern Idaho. In: Brooks, Rachel K., compiler. Proceedings of the 68th Western International Forest Disease Work Conference; 5-9 June 2023; Rohnert Park, CA. Online: https://www.wifdwc.org. p. 134-136.