Sierra Nevada Network high elevation white pine monitoring: 2013 annual report

Nesmith, Jonathan

White pine species in Sequoia and Kings Canyon National Parks (SEKI) and Yosemite National Park (YOSE) are vulnerable to several stressors including invasive pathogens, native pests, and climate change, and have been recognized as a high priority vital sign for SIEN. Currently, populations of whitebark pine (Pinus albicaulis) and foxtail pine (P. balfouriana), as well as their respective plant communities, are in better ecological condition in the Sierra Nevada compared to populations in the Cascades and Rocky Mountains (Millar et al. 2012). However, the observed steeply declining trends in white pine populations in the northern Cascades and Rocky Mountains, coupled with the identification of key stressors in SIEN parks, is a significant cause for concern about the future status of these ecologically valuable communities. Monitoring white pine forest community dynamics will allow for early detection of downward trends and identify the potential need for management intervention. White pine monitoring in SIEN is being closely coordinated with monitoring of white pine in other networks (limber pine [P. flexilis] in the Upper Columbia Basin Network [UCBN]; whitebark pine in the Klamath Network [KLMN]), using a common monitoring protocol. Thus, information from this monitoring project will contribute meaningfully to the broader regional assessment of the status and trends of white pine species across western North America. This report documents the results of the 2013 field season, which is the second year of monitoring in SEKI and YOSE. No data collection occurred in 2012 because the project was temporarily suspended following a 2011 forest crew accident. Therefore, the 2013 goal was to establish the second of three rotating panels (panel 2) for each species-park population: YOSE-whitebark pine, SEKI-whitebark pine, and SEKI-foxtail pine. Each panel consists of 12 permanent 50 x 50 meter (2,500 m2) plots that were randomly selected for each of the three populations. The current panel size reflects a reduction from what was planned in the original protocol (16 plots). The reduction was based on a re-assessment of the time required to complete a panel. Thus, there will be a total of 36 whitebark pine plots in YOSE, 36 whitebark pine plots in SEKI, and 36 foxtail pine plots in SEKI. Data from plot surveys will be used to characterize white pine forest community dynamics in SEKI and YOSE, including changes in tree species composition, forest structure, forest health, and demographics. During July 2013, we worked on the whitebark pine panel in Yosemite. We established six whitebark pine plots, rejected two, and visited an additional three (for ground-truthing purposes). From August to September, we worked on the foxtail and whitebark pine panels in SEKI. We established nine foxtail pine plots and began installation of one other. We established five whitebark pine plots, began installation in two, and rejected two others. In total, the crew visited 30 sites during the 2013 field season and completed installation of twenty of them. Species composition, forest structure, and factors affecting tree health and reproduction including incidence and severity of white pine blister rust (Cronartium ribicola) infection, mountain pine beetle (Dendroctonus ponderosae) infestation, dwarf mistletoe (Arceuthobium spp.) infection, canopy kill, and female cone production were recorded.

Sierra Nevada Network high elevation white pine monitoring: 2013 annual report

Series