Decaying logs as germination sites in northern hardwood forests

Abstract

While several authors have noted tree regeneration on decaying logs, the role that "nurse logs" play in maintaining tree diversity in eastern North American forests has remained itnqiiantified. We sampled small seedling (<5 cm high) densities of seven tree species on and directly adjacent to logs in two northern hardwood stands in the Adirondack mountains of New York. Polar ordination of 42 microsite plots revealed distinctly different small seedling communities on logs vs. forest floor. Yellow birch and red spruce densities were 24 times and 5 times greater on logs than forest floor, while those of sugar maple and striped maple were 8 times and 4 times greater on the forest floor. Maintaining a natural level (~57o ground cover) of well distributed logs can supplement site preparation techniques such as soil scarification to provide regeneration sitesfor yellow birch and red spruce, particularly in heavily stocked northern hardwood stands.