GMUG 12/15/05

1. “The MB&G Silviculture Support System”Steve FairweatherEllen VothReggie FayMason, Bruce & Girard, Inc.Portland, Oregon GMUG 12/15/05

2. MBG Silviculture Support System • Goal was to develop a simple to use desktop computer tool for the forester tasked with justifying silvicultural treatments in young stands • The tool had to be adaptable to any region of the country • Could be developed in either Access or Excel GMUG 12/15/05

3. MBG Silviculture Support System • Recall the work of Joe Buongiorno with matrix models of stand growth • e.g., Michie and Buongiorno, 1984. Estimation of a matrix model of forest growth from remeasured permanent plots. Forest Ecology and Management, 8; 127-135. • Recall Terry Harrison’s growth modeling with “pseudodata” – broadly defined as the use of models (rather than empirical observation) to collect data • Harrison and Twark, 1991. Determining forest management regimes via pseudodata analysis. Proc., 1991 Systems Analysis in Forest Resources Symposium, Charleston, SC. March 1991. Pg 46-53. GMUG 12/15/05

4. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

5. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

6. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

7. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

8. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

9. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

10. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

11. MBG Silviculture Support System • “Proof of Concept” GMUG 12/15/05

12. MBG Silviculture Support System • Concept “looked good on paper” • First application was to east-side forests in eastern Washington, northern Idaho, and western Montana (3 separate workbooks) • Client wanted to be able to import stand table data from an MBG Tools database GMUG 12/15/05

13. MBG Silviculture Support System • “Other Demands –” • Trickle function for seedlings into the 1” class • Handle mixed species stands, up to 8 species groups • Use varying stumpage rates by product; predict future yields by product (up to 6 products) • 15 periods, up to 5 years per period • Report volumes in board feet • Up to 3 silvicultural treatments in a single projection • Be able to specify discount rates, appreciation rates, product values GMUG 12/15/05

14. MBG Silviculture Support System • The DBH Growth and Mortality Matrices – • DBH ranges from .5” to 51” in 1” classes • Site index ranges from 45 to 95 in 10’ increments • Basal area ranges from 20 to 400 sq. ft. /acre in 20 sq. ft. increments • 8 species groups • 6 sites x 20 BA classes x 52 DBH classes x 8 species = 49,920 cells GMUG 12/15/05

15. MBG Silviculture Support System • The DBH Growth and Mortality Matrices – • Grew the client’s inventory in MBG Tools for 5 years using the preferred growth model (SPS, in this case) • Formed a dataset (pseudo-data!) suitable for nonlinear regression analysis, to build a model to predict annual dbh growth as function of species group, basal area per acre, site index, and tree dbh • Used the model to populate the dbh growth matrices • Proceeded similarly for probability of mortality GMUG 12/15/05

16. MBG Silviculture Support System • So …. How did it turn out? GMUG 12/15/05