Ten-year diameter and basal area growth of trees surrounding small group selection openings

Abstract

The effects of small openings in forest stands has interested silviculturists and ecologists for years. Interest generally has centered on the vegetation in the openings, not on that immediately outside of them. Quantitative information on the growth of trees adjacent to group-selection openings, although often mentioned in forestry textbooks as contributing to cost effectiveness, is scant. Five conifer and three hardwood species bordering 9-,18-, and 27-m diameter openings in the northern Sierra Nevada of California were examined for diameter growth 10 years before and 10 years after an initial group selection cutting. Ten-year diameter growth at breast height of various combinations of species and diameter classes did not differ significantly (P > 0.05) among opening sizes 10 years after cutting. But mean basal area growth of pines (ponderosa and sugar) 10 years after cutting was significantly greater (P < 0.05) than that before cutting in 18- and 27-m openings. This difference also was found for shade-tolerant conifers (Douglas-fir, incense-cedar, and California white fir) bordering all opening sizes. Mean basal area growth of hardwoods (California black oak, tanoak, Pacific madrone) did not differ before and after cutting for any opening size.

Citation

McDonald, P.M.; Ritchie, M.W.; Abbott, C.S. 1996. Ten-year diameter and basal area growth of trees surrounding small group selection openings. Northwest Science Journal. 70(4): 341-347.