Wildfire impact on Douglas fir stands in Patagonia, Argentina

GODOY, M. M.; DEFOSSÉ, GUILLERMO EMILIO; DAVEL, MIGUEL; BIANCHI, LUCAS OSVALDO

Sun City

Congreso; Wildfire 2011 - 5th International Wildland Fire Conference; 2011

In La Zeta Municipal Park of Esquel, Patagonia, Argentina, in 2003, a 21 years ald Douglas fir afforestation (Pseudotsuga menziesii) was subjected to four silvicultural treatments (thinning to Reineke´s Stand Density Index SDI of 500, 700, 900 and control). In March 2007, all plots were affected by a wildfire which presented extreme behavior. During the subsequent three growing seasons, we measured some growth parameters and percentage of dead trees, height of scorch and percentage of crown scorch. Fire effects significantly differ among treatments, and drastically diminished as the stand density decreased. The highest growth parameters were achieved when SDI indices ranged from 500 to 700. These densities appear as appropriate to withstand extreme fires at least under the conditions presented, and could be used as a reference to keep Douglas fir afforestations in wildland urban interfaces of Patagon in safe from wildfires.