Loblolly Pine Growth and Yield Research Cooperative

     PTAEDA2.1: a forest stand simulator for modeling individual tree growth and stand development in loblolly pine plantations on cutover, site-prepared areas.

     Inputs to the model are:
          age
          number of loblolly pine trees planted or surviving, or the planting spacing
          site index (base age 25)
     Outputs include:
          number of trees surviving per acre
          basal area per acre
          total and merchantable volumes per acre


     PTAEDA2.1 is a distance dependent growth and yield model using region-wide growth data from loblolly pine trees growing in site-prepared plantations. 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 Bernoulli trials. Subroutines were developed to simulate the effects of hardwood competition, thinning, fertilization and pruning 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.

Download a Demonstration Version

To download a demonstration version:
1. Click PTAEDA2 to start downloading.
2. With your web browser select "save this program to disk".
3. Run the file saved in step 2 by double clicking it. The setup utility starts.
4. Run the demo program in the destination directory of step 3.
5. The demonstration version site index is fixed.

     A detailed users manual is available at no charge. The executable computer code for Windows can be obtained for $95.00. To place an order, contact Ralph Amateis at ralph@vt.edu.

PTAEDA2.1 user manual

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