Model Description

ORGANON is a computer model of individual tree growth for areas of the Pacific Northwest.

It is an individual tree growth model that uses a list of trees, each with exact measurements, as input data. The user can specify periods of growth, in five year increments, and management such as thinning, fertilizing, and pruning. For each of the requested activities, the individual trees are modified to reflect the effects of the actions. The program produces stand statistics at each step, and yield tables after final harvest of the stand.

Presently, the ORGANON model is applicable to three areas: (1) the mixed species, even- and uneven-aged stands of Southwest Oregon with tree ages up to 350 years (SWO version), (2) young-growth (up to 120 years old) Douglas-fir and/or western hemlock even- and uneven-aged stands of Northwest Oregon (NWO version), and (3) young growth even-aged stands of Douglas-fir and/or western hemlock in western Oregon, Washington and British Columbia (SMC version). Although it will project uneven-aged stands, the NWO version was developed primarily from data taken from even-aged stands.

Overview of the input data need to run ORGANON

The trees input to the program should have the following measurements:

Point/Plot number REQUIRED An integer between 1-999 showing what group the tree belongs to.
Species Code REQUIRED Each possible species has a code assigned.
Diameter REQUIRED Diameter outside bark, in inches, 4.5 feet above ground level (DBH).
Total Tree Height RECOMMENDED Total height of tree in feet.
Crown Ratio RECOMMENDED Height to live crown divided by total height.
Radial Growth OPTIONAL Radial growth inside bark in inches. 

Use this data format:
-------  ------------------------------------------------
 Column  Variable
-------  ------------------------------------------------
  1- 3   Plot/Point Number (integer)
  5- 7   Species Code (integer)
  9-13   Diameter at Breast Height (inches) 
         (real-1 decimal place)
 15-19   Total Tree Height (feet) (real-1 decimal place)
 21-24   Crown Ratio (real-2 decimal places)
 26-31   Expansion Factor (per acre) (real-2 decimal places)
 33-37   5-year Radial Growth inside bark (inches)
 39-40   User Code (integer)
-------  ------------------------------------------------

Here is an example:



              1         2         3         4
     1234567890123456789012345678901234567890
     ----------------------------------------
      10 202  27.5 134.9  .63  25.24  2.91  1
      10 202  10.0    .0  .00    .00   .00  0
     ----------------------------------------
All optional entries may be entered as zeros (as in the second
tree above) and will be filled in by the program. For plots
that have no trees, include a record with the plot number and
zero for all other entries.

Species and Species Codes used by ORGANON

Species codes in ORGANON follow the USFS stand exam numeric codes. These are: 

Code Species        SWO NWO SMC
  -------------------------------------
    015  White fir        Y   N   N    
    017  Grand fir        Y   Y   Y    
    081  Incense cedar    Y   N   N    
    117  Sugar pine       Y   N   N    
    122  Ponderosa pine   Y   N   N    
202  Douglas-fir      Y   Y   Y
231  Pacific yew      Y   Y   Y
242  West. Red Cedar  Y   Y   Y
    263  Western hemlock  Y   N   Y    
312  Bigleaf maple    Y   Y   Y
351  Red Alder        Y   Y   Y
361  Pacific madrone  Y   Y   Y
431  Golden chinkapin Y   N   N
492  Pacific dogwood  Y   Y   Y
631  Tanoak           Y   N   N
805  Canyon live oak  Y   N   N
815  Oregon white oak Y   Y   Y
818  Calif. black oak Y   N   N
920  Willow           Y   Y   Y
   -------------------------------------
Project participants
ORGANON was developed by David W. Hann, Ph.D., professor of forest biometry. He was assisted by Arlene Hester, David Larsen, David Marshall, Doug Maguire, Martin Ritchie, John Scrivani, David Walters, and Chao-Huan Wang during development of the Southwest Oregon version. The SWO version was funded by The Forestry Intensified Research (FIR) Cooperative. Development of the Northwest Oregon (NWO) version was assisted by Arlene Hester, David Marshall, Martin Ritchie, Chao-Huan Wang, and Abdel Azim Zumrawi. It was funded by The College of Forestry Research Properties, Oregon State University. Development of the Stand Management Cooperative (SMC) version was assisted by David Marshall, Christina Olsen, Charles Aylworth, and Mark L. Hanus. It was funded by the Stand Management Cooperative, University of Washington, Seattle.
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For Questions and User Support
Contact: organon@oregonstate.edu