The Climate Response of P. lambertiana, P. monticola, and P. jeffreyi in Yosemite and Sequoia National Parks, California

This research investigates the sub-annual climate response of ten Pinus lambertiana and eight Pinus jeffreyi from Yosemite, and ten Pinus monticola and ten Pinus jeffreyi from Sequoia. We investigate the potential of using resin ducts to measure the earlywood and latewood of P. lambertiana and P. monticola and compare this growth with co-occurring, traditionally measured P. jeffreyi. Correlation analyses of ring widths with average monthly temperature, vapor pressure deficit (VPD), and precipitation were conducted. Our results show that the resin duct method performed poorly at both sites but better with P. lambertiana at Yosemite. Species at both sites generally have a positive correlation with precipitation. Earlywood and latewood correlations with climate were relatively weak. Temperature and VPD correlations were generally positive in the spring and negative in the summer months at both sites for all three species. These results reveal that future increases in temperature and VPD will leave these trees vulnerable to future droughts. More samples are needed throughout the Sierras to determine if the resin duct method can be used for sub annual climate reconstructions, if these results can be generalized, and if sub-annual reconstructions are possible for these three species.