Ten-year growth and survival of northern red oak seedlings planted in a Central Appalachian strip clearcut

Abstract

Upland oaks are a keystone group of trees throughout Central Appalachia. However, there has been difficulty in regenerating oak dominated forests. In addition, existing methods to regenerate oak-dominated forests can be costly, damaging to residual trees, and may require upfront investment before any economic return is seen. Methods which provide a compromise between actively creating competitive oak advance reproduction and providing economic near-term revenues are needed. We hypothesized that a strip clearcut method, where one-half of the area is cut in strips and the residual area is removed 5–10 years after, could create competitive advance reproduction due to improved understory light conditions while providing up front revenue for landowners. We harvested 45 m (150 ft) wide strips oriented north to south on a high-quality site in Central Appalachia in the fall of 2014 and planted 360 northern red oak seedlings the following spring. Seedlings were planted in 8 positions across residual/cut strip pairings which represented a gradient in light availability. Seedling survival was greatest within residual strips, and lowest within cut strips, although average growth was greater in the cut strips. Seedlings along strip edges had the best combination of survival (about 70 %) and growth with the average height of edge seedlings exceeding 91 cm (minimum height of competitive seedlings) in 2024. We also used dominance probabilities to calculate the required planting density to regenerate 20 % stocking of dominant and codominant oaks 20 years after harvest. Ten years following the initial strip harvests, based on the survival and growth of planted seedlings, the required planting density ranged from 2500–4500 trees/ha to meet a 20 % stocking goal.