Coast redwoods (sequoia sempervirens) are not serotinous. Giant sequoia (sequoiadendron giganteum) are, but that's not what's in Big Basin.

Coast redwoods propagate by stump sprouting and seeds which don't require fire. Fire is important in their ecosystem for clearing out fuel but is not at all required for reproduction.

https://ucanr.edu/sites/forestry/California_forests/http___u...