15 September 2003 SMC Fall Policy Meeting TreeLab (v1.0) Variable-density Yield Simulator for Immature, Managed Stands of Douglas-fir Sam D. Pittman Eric C. Turnblom

15 September 2003SMC Fall Policy Meeting TreeLab – Topics Introduction / background Introduction / background Model / Theory Model / Theory Operation / Output Operation / Output Results / Discussion Results / Discussion Conclusions / Questions Conclusions / Questions

15 September 2003SMC Fall Policy Meeting TreeLab - Introduction Early Growth & Development of Immature, Managed Stands of Douglas-fir Early Growth & Development of Immature, Managed Stands of Douglas-fir Basically targeted the use of Type I and II installations to develop variable-density, managed stand growth & yield tables Basically targeted the use of Type I and II installations to develop variable-density, managed stand growth & yield tables TreeLab is a variable-density, managed stand simulator fit to all Type I and II data TreeLab is a variable-density, managed stand simulator fit to all Type I and II data

15 September 2003SMC Fall Policy Meeting TreeLab - Introduction (2) Turnblom, E.C. and T.E. Burk Modeling self- thinning of unthinned Lake States red pine stands using nonlinear simultaneous differential equations. Can. J. For. Res. 30: Turnblom, E.C. and T.E. Burk Modeling self- thinning of unthinned Lake States red pine stands using nonlinear simultaneous differential equations. Can. J. For. Res. 30: Pittman, S.D. and E.C. Turnblom A study of self-thinning using coupled allometric equations: implications for coastal Douglas-fir stand dynamics. Can. J. For. Res. 33: Pittman, S.D. and E.C. Turnblom A study of self-thinning using coupled allometric equations: implications for coastal Douglas-fir stand dynamics. Can. J. For. Res. 33: The model in TreeLab extends the previous work by including the simulation of fertilization and thinning treatment regimes The model in TreeLab extends the previous work by including the simulation of fertilization and thinning treatment regimes

15 September 2003SMC Fall Policy Meeting TreeLab – Model Theory Every stand has a unique self-thinning trajectory boundary driven by its unique stand allometry Every stand has a unique self-thinning trajectory boundary driven by its unique stand allometry Stand allometry is dynamic, not static; allometric relationships change with stage of development Stand allometry is dynamic, not static; allometric relationships change with stage of development Dynamic allometry is captured through simultaneous, coupled rate equations Dynamic allometry is captured through simultaneous, coupled rate equations

15 September 2003SMC Fall Policy Meeting TreeLab – Model Theory (2) The rate at which a stand variable changes is found by differencing gross growth & respiration (anabolic & catabolic processes, respectively) The rate at which a stand variable changes is found by differencing gross growth & respiration (anabolic & catabolic processes, respectively) The magnitudes of the anabolic and catabolic processes depend on the current state of the stand and is affected by site quality The magnitudes of the anabolic and catabolic processes depend on the current state of the stand and is affected by site quality The current state of the stand can be described by the triplet (stand basal area, quadratic mean DBH, and dominant height) The current state of the stand can be described by the triplet (stand basal area, quadratic mean DBH, and dominant height)

15 September 2003SMC Fall Policy Meeting TreeLab –Model Theory (3) For TreeLab, the site quality rate adjustment factor was modified to allow for fertilization and any interaction between the two: For TreeLab, the site quality rate adjustment factor was modified to allow for fertilization and any interaction between the two:

15 September 2003SMC Fall Policy Meeting TreeLab – Operation / Output Conventional “Windows” interface giving Point & click operation Conventional “Windows” interface giving Point & click operation How to define stand parameters and treatment actions How to define stand parameters and treatment actions How to print and / or save yield table output How to print and / or save yield table output

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting

15 September 2003SMC Fall Policy Meeting TreeLab – Results / Discussion Three example treatment regimes: 1) do nothing, 2) thinning RD55 -> RD35, and 3) fertilizing every twenty years, beginning in first year; two initial conditions: Three example treatment regimes: 1) do nothing, 2) thinning RD55 -> RD35, and 3) fertilizing every twenty years, beginning in first year; two initial conditions:

15 September 2003SMC Fall Policy Meeting TreeLab – Results / Discussion Low site QMD evolution: Low site QMD evolution:

15 September 2003SMC Fall Policy Meeting TreeLab – Results / Discussion Low site (derived) TPA evolution: Low site (derived) TPA evolution:

15 September 2003SMC Fall Policy Meeting TreeLab – Results / Discussion High site BA evolution: High site BA evolution:

15 September 2003SMC Fall Policy Meeting TreeLab – Results / Discussion High site H40 evolution: High site H40 evolution:

15 September 2003SMC Fall Policy Meeting TreeLab – Conclusion Model propositions Model propositions Unique self-thinning boundary for each stand Unique self-thinning boundary for each stand Stand allometry is dynamic, not static Stand allometry is dynamic, not static Changes in stand attributes are represented as a coupled system of rate equations that govern allometry Changes in stand attributes are represented as a coupled system of rate equations that govern allometry Uses all Type I and II data including fertilization and thinning available through growth year 2000 Uses all Type I and II data including fertilization and thinning available through growth year 2000 Output consistent with range of data spanned Output consistent with range of data spanned

15 September 2003SMC Fall Policy Meeting TreeLab – Conclusion Please visit Please visit To download, click on the TREELAB link (LHS) To download, click on the TREELAB link (LHS) Discussion Discussion Eric C. Turnblom Eric C. Turnblom