Eight-Year Regeneration Response to Gap-Based Irregular Shelterwood Practices in Oak Dominated Stands Near Berea, Kentucky

This research examined regeneration dynamics following gap-based irregular shelterwood practices in intermediate productivity oak (Quercus)-dominated stands located in Berea College Forest, Berea, KY, USA. Established in 2012, the study includes 12 experiment units comprising a circular harvest gap (30 m radius) and a matrix zone delineated around the circumference of the gap, which extended 30 m from the gap edge into the adjacent forest. A midstory removal treatment was performed within six of the experiment units’ matrices, while six matrices were left untreated (control). Belt transects extending 60 m from gap center to the end of the matrix zone were established within each experimental unit to quantify oak regeneration dynamics. Nested regeneration surveys (radius: 1.13 and 1.7 m) were established every 10 m along each transect, along with one plot at the center of the gap to quantify regeneration dynamics of woody competitors. Eight-year height growth and total heights of oaks were greatest within the gap decreasing towards the gap edge and plateauing in the adjacent forest matrix. Within the gap and at gap edge, woody non-oak stems were taller than oak reproduction, providing evidence that gap edge was not successful in enhancing the competitive ability of oak. Tree density had few statistically significant differences among species when compared across location-treatments, distance categories and years. The midstory removal matrix treatment did not show an enhanced effect on oak height or density in comparison to the untreated matrix