• Bataineh, Mohammad
  University of Arkansas
  

Natural regeneration remains the dominant method for the development of new stands in the Northern Forest. This trend is expected to continue in the future in light of the growing prominence of partial harvesting. Limited understanding of how partial harvesting practices, and biotic and abiotic factors influence regeneration composition (species) and abundance (number of regeneration) restricts ourability to evaluate management alternatives and project future wood supply. The objectives of this project were to: 1) quantify the relation between overstory, site, and understory characteristics; 2) identify key factors and constraints associated with regeneration of desired species; and 3) develop predictive models that can be incorporated into the Acadian Variant of FVS. The objectives were evaluated both at the stand- and the landscape-level using the long-term measurement plots of Penobscot Experimental Forest and the US Forest Service Forest Inventory and Analysis dataset, respectively. At the stand-level, the regeneration abundance was primarily associated with the local site factors including overstory composition and soil attributes. Harvesting treatments were less influential in explaining the pattern of natural regeneration abundance and composition relative to biotic (e.g.,overstory structure and composition) at the stand-level. Our results showed, mean annual temperature and overstory tree-size diversity were the most important abiotic and biotic variable, respectively to explain the abundance and composition of natural regeneration at the landscape-level. Our results indicate, the moderate growing condition and moderate overstory tree-size diversity incorporate higher number of species as well as higher number of regeneration than productive/poor growing conditions or uniform/highly diverse overstory. Our models are ready to incorporate into the Acadian Variant of FVS. The overall results suggest low intensity partial harvesting will not be enough to change the regeneration composition (e.g., balsam fir to red spruce or American beech to sugar maple). Site preparation treatments including soil scarification, controlling browsing pressure, and controlling the regeneration of aggressive species (e.g., American beech) are necessary.