Sprouting response of Quercus arizonica and Quercus emoryi following fire

Abstract

Sprouting response of Quercus emoryi and Quercus arizonica was studied following a May, 1987 wildfire on the Audubon Society Research Ranch Preserve in Santa Cruz, Co., AZ. Sprouting response of oaks was measured as total number and density of sprouts by species and diameter class. Thirty-five of the 109 trees examined (32%) sprouted in response to the fire, including 30.5% of all Q. emoryi and 36.4% of all Q. arizonica. In both species, small diameter (10 cm) trees are more likely to sprout than those larger than 10 cm. Quercus emoryi trends toward producing more sprouts/tree than Q. arizonica (avg. of 14.03 sprouts to 6.87 sprouts). Among all sprouters, however, there is no difference in the number of sprouts produced by trees in the two size classes. Sprout density is greater in Q. emoryi at 3.58 sprouts/cm. Q. arizonica averages 0.89 sprouts/cm. In all sprouters, density is greater in smaller stems (4.17 sprouts/cm) compared with 0.71 sprouts/cm in the larger size class.