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Departmental Publications, Forest Resources and Environmental Conservation

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https://hdl.handle.net/10919/23968
Newsletters, annual reports, and other departmental publications

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Browsing Departmental Publications, Forest Resources and Environmental Conservation by Author "Amateis, Ralph L."

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    Simulation of Individual Tree Growth and Stand Development in Loblolly Pine Plantations on Cutover, Site-Prepared Areas
    Burkhart, Harold E.; Farrar, Kenneth D.; Amateis, Ralph L.; Daniels, Richard F. (Virginia Tech. Division of Forestry and Wildlife Resources, 1987)
    A forest stand simulator, PTAEDA2, was developed to model growth in loblolly pine (Pinus taeda L.) plantations on cutover, site-prepared areas. Individual trees were used as the basic growth units. In PTAEDA2, trees are assigned coordinate locations in a stand and 'grown' annually as a function of their size, the site quality, and the competition from neighbors. Growth increments are adjusted by stochastic elements representing genetic and microsite variability. Mortality is generated stochastically through Bernouli trials, Subroutines were developed to simulate the effects of hardwood competition, thinning, and fertilization on tree and stand development. Options for varying the spatial location of trees to mimic randomness in machine and hand planting operations are also included.
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    Yields and Size Class Distributions for Unthinned Loblolly Pine Plantations on Cutover Site-Prepared Lands
    Amateis, Ralph L.; Burkhart, Harold E.; Knoebel, Bruce R.; Sprinz, Peter T. (Virginia Tech. Division of Forestry and Wildlife Resources, 1984)
    Data from plots established in unthinned loblolly pine plantations on cutover site-prepared lands were used to develop size class distribution and yield predictions. The data come from plantations of loblolly pine established over much of its natural range and represent a wide variety of stand conditions and site-preparation treatments. A three parameter Weibull density function was used to model diameter distributions, and a computer program, COYIELD, was developed to predict yields from stand attributes. The predicted yields should satisfactorily represent many sites in the Piedmont and Coastal Plain regions of the Southern United States.