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Full-Text Articles in Forest Management
Spatial Aspects Of Tree Mortality Strongly Differ Between Young And Old-Growth Forests, Andrew J. Larson, James A. Lutz, Daniel C. Donato, James A. Freund, Mark E. Swanson, Janneke Hillrislambers, Douglas G. Sprugel, Jerry F. Franklin
Spatial Aspects Of Tree Mortality Strongly Differ Between Young And Old-Growth Forests, Andrew J. Larson, James A. Lutz, Daniel C. Donato, James A. Freund, Mark E. Swanson, Janneke Hillrislambers, Douglas G. Sprugel, Jerry F. Franklin
Forest Management Faculty Publications
Rates and spatial patterns of tree mortality are predicted to change during forest structural development. In young forests, mortality should be primarily density dependent due to competition for light, leading to an increasingly spatially uniform pattern of surviving trees. In contrast, mortality in old-growth forests should be primarily caused by contagious and spatially auto-correlated agents (e.g., insects, wind), causing spatial aggregation of surviving trees to increase through time. We tested these predictions by contrasting a three-decade record of tree mortality from replicated mapped permanent plots located in young (<60-year-old) and old-growth (>300-year-old) Abies amabilis forests. Trees in young forests died at a …
Spatially Nonrandom Tree Mortality And Ingrowth Maintain Equilibrium Pattern In An Old-Growth Pseudotsuga–Tsuga Forest, James A. Lutz, Andrew J. Larson, Tucker J. Furniss, Daniel C. Donato, James A. Freund, Mark E. Swanson, Kenneth J. Bible, Jiquan Chen, Jerry F. Franklin
Spatially Nonrandom Tree Mortality And Ingrowth Maintain Equilibrium Pattern In An Old-Growth Pseudotsuga–Tsuga Forest, James A. Lutz, Andrew J. Larson, Tucker J. Furniss, Daniel C. Donato, James A. Freund, Mark E. Swanson, Kenneth J. Bible, Jiquan Chen, Jerry F. Franklin
Forest Management Faculty Publications
Mortality processes in old-growth forests are generally assumed to be driven by gap-scale disturbance, with only a limited role ascribed to density-dependent mortality, but these assumptions are rarely tested with data sets incorporating repeated measurements. Using a 12-ha spatially explicit plot censused 13 years apart in an approximately 500-year-old Pseudotsuga–Tsuga forest, we demonstrate significant density-dependent mortality and spatially aggregated tree recruitment. However, the combined effect of these strongly nonrandom demographic processes was to maintain tree patterns in a state of dynamic equilibrium. Density-dependent mortality was most pronounced for the dominant latesuccessional species, Tsuga heterophylla. The long-lived, early-seral Pseudotsuga menziesii …