<p>Repeated high-severity fire is threatening forest resilience in dry and mesic forests of the Sierra Nevada and southern Cascades of California, USA. While impacts to plant communities have been described, the belowground effects of this fire regime change are less known. Here, we: (1) describe trends in reburn activity in the Sierra Nevada and southern Cascades, (2) conduct a case study on the effect of repeated high-severity fire on soil biogeochemistry within Plumas National Forest, California, and (3) propose a conceptual framework to describe hypothetical belowground effects of repeated high-severity fire on soil biogeochemistry and the soil microbiome by drawing on our case study and available literature. We found that yearly ≤ 20 y reburn area (yearly burned area that has also burned within 20 y prior) and yearly ≤ 20-y <i>high-severity</i> reburn area (where both initial and repeated burn events were of high severity) are increasing across the Sierra Nevada and Southern Cascades. Our framework suggests that soil carbon and nitrogen (in bulk soil and soil organic matter fractions) may be resistant to additional decline with recurrent fire. However, declining post-fire inorganic N pulses with recurrent fire, the inability of soil organic matter to recover between fires, and an altered microbial community may impact ecosystem recovery. These findings may be pertinent to dry and mesic forests beyond our study region.</p>