Linking seed and leaf litter traits to post-fire recovery and forest flammability in southeastern U.S. forests

Abstract

Decades of fire exclusion affected upland forests of the southeastern United States in many ways, including reductions in successful natural regeneration of fire-dependent species and shifts in forest flammability. To better understand natural regeneration of southern pine species, we tested the seed germination responses of southern pine species to increased soil temperature and decreased soil moisture and investigated relationships between cone production and seed production, size, and germination in longleaf pine. Because forest flammability is heavily driven by species composition and leaf litter fuel traits, but also top-down controls associated with climate/weather and fire history, we integrated conventional measurements of leaf litter traits associated with flammability at the species level across regional/climatic and fire frequency gradients. Recognizing nuances of seed and leaf litter traits will provide natural resource managers with better understanding of post-fire recovery and forest flammability in these forest systems.