This study was conducted to measure the effects of thinning coppice on Emory oak (Quercus emoryi). Thinning treatments were applied to sprouts of different ages. Height and diameter measurements were taken immediately after thinning and again one year later. Sprouts were classified into 5 age groups, 4 stump diameter groups, and 4 residual sprout groups. The interactions of these treatments and their effect on volume growth were analyzed. The results showed volume growth per stump was directly related to the number of sprouts per stump; volume growth per sprout was inversely related to the number of sprouts per stump; volume growth per stump and per sprout were both significantly affected by the age of the sprout at the time of thinning; and that stump diameter size had no significant effect on volume growth.

Emory oak (Quercus emoryi) and Arizona white oak (Q. arizonica), currently being harvested for fuelwood in encinals of southern Arizona, usually regenerate through stump sprouting. Adjacent to a Huachuca Mountains fuelwood cutting area, 3 replications of four thinning treatments (25%, 50%, 75%, and 100% intensity) were established in January, 1986. Regeneration was assessed one year later by examining the effects of thinning intensity, partial or complete stem cluster cutting, and tree characteristics. Clearcutting greatly increased the proportion of stumps that sprout for Emory oak and increased sprout volume production for both species in comparison to thinned plots. Partially cut multi-stemmed tree clusters were less likely to sprout and have less sprout volume growth after one year than completely cut clusters. Regression models were developed to estimate sprout volume production based on thinning intensity, percent stem basal area cut, tree vigor, number of tree stems, and heart rot.