Survivorship and Growth of Oak Regeneration in Wind-Created GapsThis article is part of a larger document. View the larger document here.
The effects of wind on upland hardwood forest structure and composition have been studied mostly in the context of either one to two tree mortality gap-phase openings or in retrospective studies of ancient disturbances. Larger (> 0.1 ha) wind-created openings are common across Southern Appalachian landscapes and can be an important factor in shaping understory colonization, growth, and survival. I investigated the relationships of oak seedling survivorship and growth to spatial and structural gradients in and around large hurricane created gaps on the Bent Creek Experimental Forest. I related 2-year tagged-seedling survivorship to distance from gap edge and physical site through logistic regression. Seedling survivorship declined progressively on a linear distance gradient from gap exterior to gap center. Survivorship also declined as microsite soil moisture increased. I used multiple nonlinear regressions to relate 2-year tagged-seedling basal diameter growth and height growth to distance from gap edge, initial seedling height, canopy cover, and physical site. Basal diameter growth increased as midstory canopy cover declined, at gap positions close to gap center, as initial seedling height increased, and as microsite soil moisture increased. Seedling height growth increased with decreasing overstory canopy cover, at locations near gap center, as initial seedling height increased, and as microsite soil moisture increased.