Silver, Emily Jane2012-12-102012-12-102012-07https://hdl.handle.net/11299/140681University of Minnesota M.S. thesis. July 2012. Major: Natural Resources science & management. Advisors: Anthony W. D’Amato, Shawn Fraver. 1 computer file (PDF); viii, 86 pages, appendices A-B.The developmental dynamics and structure of old-growth forests often serve as important baselines for forest management. Nonetheless, long-term information on natural patterns of development and mortality is rare for many commercially and ecologically important forest types. This study uses a long-term dataset from a large (2 hectare), stem-mapped plot within an old-growth Pinus resinosa (red pine) forest in Itasca State Park to quantify patterns of forest structural development and mortality events over an 87-year period. These patterns were compared with those found in other old-growth red pine -dominated forests in northern Minnesota, as well as with unmanaged second-growth and extended rotation red pine forests to quantify the range of variation in structural conditions and to evaluate the effectiveness of extended rotation forestry at promoting the development of late-successional structural conditions. Old-growth forests were more structurally complex than unmanaged secondgrowth and extended rotation red pine systems, due in large part to the significantly higher volumes of coarse woody debris, higher snag densities, and spatially random patterns of mortality found in old growth. Nonetheless, extended rotation thinning treatments, by accelerating advancement to larger tree diameter classes, generated diameter distributions closely approximating those found in old growth. These results suggest that extended rotation treatments may accelerate the development of old-growth structural characteristics, provided that random patterns of mortality are emulated and coarse woody debris and snags are deliberately retained and created on site. These and other developmental characteristics of old-growth systems can inform red pine management when management objectives include the restoration of late-successional forest conditions.en-USNatural Resources science & managementThesis or Dissertation