Patterns of leaf area and growing space efficiency in young even-aged and multiaged coast redwood stands

Abstract

Projected leaf area estimates were used to predict volume increment and basal area of second-growth coast redwood ( Sequoia sempervirens (D. Don) Endl.) trees on Jackson Demonstration State Forest, Mendocino County, California. Sample plots were established within even-aged and multiaged mixed-species stands. Redwood tree basal area growth was more strongly related to sapwood area than to tree size and differed significantly between canopy strata and overstory stratum crown classes. Projected leaf area was predicted from sapwood area for each tree, and summarized to the stand level, giving a maximum stand leaf area index (LAI) estimate of 14.9 m2/m2. Redwood tree growing space efficiency (GSE; the ratio of stem volume increment to leaf area) was greatest on average among emergent overstory trees, followed by dominant and codominant overstory trees. There was no evidence of declining overstory tree GSE with increasing leaf area over the range of data collected. A nonlinear model predicted increasing understory tree GSE with increasing leaf area. Models that predict basal area and LAI were developed to permit implementation of GSE models from basic inventory data.