Fire history of mixed-conifer forests on the North Rim, Grand Canyon National Park, Arizona
Wolf JJ and Mast JN. 1998. Fire history of mixed-conifer forests on the North Rim, Grand Canyon National Park, Arizona. Physical Geography. 19(1):1-14
This study determined fire history in the mixed-conifer forest in the Grand Canyon National Park to assess occurrences of natural fires prior to Euro-American settlement. The study analyzed the gradient from the lower to the upper ecotones of the mixed-conifer forest. Ponderosa pine (Pinus ponderosa) dominates the lower ecotone, while the middle elevation is a mixture of ponderosa pine and white fir (Abies concolor). Engelmann spruce (Picea engelmanni) occurs in the upper ecotone. All sites are currently invaded by shade tolerant white fir, a fire intolerant species. Master chronologies were constructed for each elevation using wedges and core samples from older larger trees. Fire scars were cross-dated from the chronologies to obtain fire years. Results show pre Euro-American settlement fire intervals (prior to 1870) were less frequent than the settlement era ( 1870-1919), but more frequent than the suppression era ( 1920- 1995). Seasonality, determined by detecting the position of each fire scar within the annual ring, showed the majority as late summer fires. Fire history provides essential information for understanding forest dynamics, as well as for developing fire management program alternatives.
- Type
- Journal Article
- Authors
- Wolf, Joy; Mast, Joy
- Units
- GRCA
- Keywords
- FIRE, Fire History, Forest dynamics, Forest Fires, Walhalla Plateau (Ariz.)