Fire, tree invasion, and ecological memory: Montane chaparral in California s Southern Cascades

Catherine Airey, Penn State

April 12, 2012 @ 01:20 pm to 02:10 pm

111 Tyson Building

In the mid-montane forests of Northern California, before fire suppression was implemented in the early 1900s, periodic mixed severity fires influenced forest structure and composition. Treeless shrub-dominated patches known as montane chaparral are part of the forest thought to have been created by high severity fire. A century without fire may have allowed trees to invade chaparral. This study investigated the temporal and spatial dynamics of chaparral and tree establishment in chaparral vegetation in the Southern Cascades of Lassen Volcanic National Park, California. We found that the oldest chaparral established after a fire event and were older than most trees.__Chaparral were multi-aged indicating continued resprouting. Tree density decreased with distance from forest edge suggesting gradual invasion. An evaluation of severity patterns from recent wildfires suggests that pre-suppression chaparral dominated areas may be more likely than surrounding forest to burn with high severity. This study could contribute to our understanding of how to restore, manage, and predict potential future changes in the mid-montane forest landscape.

Contact

Jason Hill
ecologyservice@psu.edu