A 2019 study by Meyer and others showed that the reestablishment of natural fire regimes can be highly effective at restoring the structure and understory diversity of red fir forests but have little effect on the health of red fir under increasing moisture stress associated with drought and warming climate.
Marc Meyer, Becky Estes, Amarina Wuenschel, Beverly Bulaon, Alexandra Stucy, Douglas Smith, and Anthony Caprio. 2019. Structure, diversity and health of Sierra Nevada red fir forests with reestablished fire regimes. International Journal of Wildland Fire 28, 386–396. https://doi.org/10.1071/WF18114