Analysis of fire-related Vegetation Patterns in the Huachuca Mountains, Arizona, USA, and Sierra los Ajos, Sonora, Mexico

There is general interest among fire ecologists to integrate observed fire regimes into long term fire management. The United States-Mexico borderlands provide unique research opportunities to study effects of contrasting forest management activities on forest structure and pattern. To increase understanding of the range of forest stand conditions in borderland ecosystems, we compared tree crown patterns from two forests near the US- Mexico border that are managed under contrasting fire policies and have contrasting fire histories. Locations of individual tree crowns in geographically and ecologically matched forest patches were detected and plotted from Digital Orthophoto Quarter Quadrangles (DOQ) using a semi-automated crown detection procedure. Spatial patterns of tree crowns were analyzed with point pattern methods. Results describe disparate spatial patterns and levels of crown density in fire-managed forests of the US and unmanaged forests of northern Mexico.