Tree List Generator (TLG) v1.0 Kevin R. Gehringer Eric C. Turnblom 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Topics Introduction / background Models / Methods Results / Discussion Operation / Output Future work / conclude 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Introduction Initial tree list estimation for individual tree based growth models Basically targeted use of the SMC-ORGANON modeling database to develop a methodology for generating initial tree lists Tree List Generation Database software provides a means for producing reasonable tree lists for a forest stand based on a minimal amount of information, such as SI, age, TPA, etc. 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Introduction (2) Tree list is a compatible set of DBH and height measurements for each tree as well as species TLG is designed for managed, mixed species stands of Douglas-fir and western hemlock as dominant species (with mixtures of other minor species) Untreated stands and thinned stands throughout southwestern British Columbia, Washington and Oregon west of the Cascade Crest 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Introduction (3) Tree list generation requires four things: A method for classifying stands A method for selecting an appropriate stand class A method for generating a tree list from a stand class A wide variety of stand measurement data sets Useful to think under the framework of generating a random stand of trees using a small set of stand attributes as the “seed” Several ways to define and implement the first three requirements… 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Methods Weibull density distribution based methods Weibull is strongly unimodal Represents flat distributions poorly Mixed species stands present challenges Parameter prediction functions may change with new data Non-parametric, density estimation methods (e.g., B-splines, etc.) 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Methods (2) Tree List Generation Database method Explicit classification based on a multidimensional histogram (data “speaks for itself”) Histogram is a consistent estimator of a density function Histogram allows refinement of its classification if sufficient data warrant higher resolution Histogram does not require reevaluation of classification rules when new data is added Histogram dimensions are stand attributes, e.g., site index, QMD, stand type, etc 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Methods (3) Tree List Generation Database method (cont’d) Stands with similar attributes belong to same hist. Bin Given a set of desired stand attributes, similarity scores are calculated for stands defined by the tree list generation database The “k” smallest similarity scores are used to select the collection of stands to form the canonical stand from which a tree list may be generated 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Methods (4) Two fundamental assumptions Forest stands, or sample plots, having similar attributes, e.g., site index, QMD, species composition, etc., are similar Attributes of forest inventory data collected from a representative set of sample plots from within a larger stand may be extended to the whole stand 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Results Simulated stands generally agreed with the actual stands they were generated to mimic at the individual tree level defined by DBH, height and species Based on a single random “draw” For DBH alone, misclassification rate was 2.6% For height, misclassification rate was 13.2% For species comp., misclassification was 8.3% 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Operation Conventional “DOS” command line interface Stand Description files specify input values for the set of measured or desired attributes used as the histogram bin dimensions for which a simulated tree list is desired comments appear after a “%” sign “KEYWORD = VALUE” format defines desired attributes 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Operation % Example stand description file TREATMENT_TYPE = UNTREATED SITE_INDEX = 140.0 STAND_TOTAL_AGE = 57.0 STAND_ORIGIN = NATURAL STAND_DENSITY = 160.0 QMD = 12.6 STAND_TYPE = PURE_DF 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Operation Random Measurement files are produced by the tree list generation process and contain attributes for the stand and a simulated stand of trees Three files are needed to set up or change the stand classification attributes Schema file: defines multidimensional histogram bin dimensions Species mapping file: maps 2-6 char. Code to integer Stand measurement file: added to tree database 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Future work Add new Type I and Type III data to the set of stand measurement files included in the tree list generation database distribution set Add Graphical User Interface (GUI) such as is used with DFSIM, that is, DFSIMIN 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. TLG - Possible GUI 15 September 2003 SMC Fall Policy Committee Mtg.

SMC Fall Policy Committee Mtg. Tree List Generator Please visit <http:://www.standmgt.org/> Click on the SOFTWARE link on L.H.S. Questions / Comments ? Kevin R. Gehringer Eric C. Turnblom 15 September 2003 SMC Fall Policy Committee Mtg.