Suppression of an invasive pine by a native shrub following a megafire

Seedling density of the Chilean wineberry Aristotelia chilensis negatively correlates with the seedlings’ abundance of an invasive pine Pinus radiata , particularly in post-fire areas. This pattern emerged following a megafire in Chile’s Coastal Maulino Forest, a biodiversity hotspot facing increasing fire threats. This pattern, coupled with a high proportion of plots lacking pine seedlings, suggests that A. chilensis may play a role in limiting P. radiata invasion. The negative relationship was strongest in areas with moderate fire severity, likely reflecting differences in shade tolerance. A. chilensis , a light-demanding species with some degree of shade tolerance, can persist in partially shaded environments. In contrast, P. radiata , a more strictly light-demanding species, struggles to establish under significant shade. In high-severity fires, however, we found no significant relationship between these species, likely due to detrimental effects on both species, including potential microbiome dependence for A. chilensis . As A. chilensis shows successful establishment at low fire severity, enhancing its post-fire recruitment, particularly in moderately burned areas, could be a valuable strategy for mitigating P. radiata invasion and restoring fire-affected Mediterranean ecosystems.