Use of FVS for a Forest-wide Inventory

1. Use of FVSfor a Forest-wide Inventory SPOKANE INDIAN RESERVATION

2. What I will cover • Introduction to the Spokane CFI • Summary data: overall trends • Analysis methods • FVS method • Results of FVS projections • Comparison of methods

3. Spokane Reservation CFI System • Established in 1957 • Remeasured 5 times since initiated • Last remeasurement done 1998 – 1999 • Includes 994 one-fifth(1/5) acre plots • Commercial forest area of reservation is about 104,000 acres

4. Comparison of Measurements: Stocking per acre

5. VolumesAre Increasing Overall Stocking Changes 1985 to 1998 Basal Area / acre remained the same Cubic-foot vol / acre increased 9% Board-foot vol / acre increased 22% (based on 257-plot sort)

6. Growth Rates are Slowing, Mortality Increasing Board-ft Growth, Harvest, and Mortality Changes, 1985 to 1998 Growth rate has decreased 18% Harvest has increased 31% Mortality has increased 103% (based on 257-plot sort)

7. Trends in Mortality as It Impacts Net Growth

8. Stand Age Conditions

9. Stratification of the Inventory Data Data were sorted into four groups based on site quality • Dry Pine: Dry ponderosa pine climax types • Pine-fir: Ponderosa pine/snowberry & dry Douglas-fir climax types • Ninebark: Douglas-fir & grand fir /ninebark types • Wet grand fir: Grand fir/twinflower and wetter

10. Inventory StrataSpokane Indian Reservation

11. ANNUAL ALLOWABLE CUT CALCULATIONS Austrian Formula – used in 1985 Area Volume Check Method – used in 1985 Forest Vegetation Simulator Model (FVS) – New method

12. Austrian Formula Method Three different alternatives were tried which varied the target future volumes

13. Austrian FormulaNo target future volume used

14. Area-Volume Control Check Method Summary of results

15. FVS Projections

16. Questions to address through FVS • What yields are produced simulating current management practices over the next 40 to 50 years? • Does FVS forecast an increase in mortality that might significantly impact yields? • Will the current age-class distribution of the forest result in a future down-cycle in harvest yields? • Can FVS be used to identify the more vulnerable components of the forest as a means to focus harvest in the coming decade? • Does FVS indicate differing yields on a long-term basis using other alternatives to current management?

17. Model calibration and adjustments • Large tree diameter growth (READCORD) • Large tree height growth (FIXHTG) • Regeneration inputs • Mortality (BAMAX) • Mortality (MORTMULT) • Mortality (Western Root Disease Model)

18. Stratum summary data

19. FVS Base Parameters by Stratum

20. Condition statement criteria • Stand age • Total basal area per acre • Sawtimber basal area per acre • Total number of trees per acre • Number of trees per acre of saplings and/or pole sizes • Ratio of cubic-foot mortality to cubic-foot stocking • Stand mistletoe rating • Quadratic mean diameter

21. Management activities invoked • Initial input of regeneration • Overstory removal • Precommercial thinning, alt. 1 & 2 • First commercial thinning, alt. 1 & 2 • Second commercial thinning • Regeneration: Low volume stocking • Regeneration: High mortality • Regeneration: High mistletoe rating • Mature stand maintenance thin

22. Management options considered • Regeneration unit size (uneven-aged vs. even-aged) • Regeneration type, Natural vs. Planted * • Regeneration density • Precommercial thinning

23. Combining the FVS projections • CFI plots were grouped by stratum but projected individually • Plot projections were combined in the FVSSTAND post-processor to produce a summary for each stratum • FVSSTAND output tables were read into spreadsheets and expanded by acreages to produce “All Strata” summaries

24. Results of FVS Projections

25. Projected changes in board-foot stockingDry Pine Stratum

26. Projected changes in board-foot stockingPine-fir Stratum

27. Projected changes in board-foot stockinNinebark Stratum

28. Projected changes in board-foot stockingWet Grand fir Stratum

29. Projected changes in board-foot stockingLodgepole Stratum

30. Projected changes in board-foot stockingAll strata

31. Harvest trends for all strata

32. Projected changes in harvest yieldsAll strata

33. Projected changes in mortalityDry Pine stratum

34. Projected changes in mortalityPine-fir stratum

35. Projected changes in mortalityNinebark stratum

36. Projected changes in mortalityWet Grand Fir stratum

37. Projected changes in mortalityLodgepole stratum

38. Projected changes in mortalityAll strata

39. Comparison of Methods

40. Overview of the results

41. Conclusions • FVS estimated a harvest level for the first 20 years that was in line with other AAC computation methods • FVS estimated a harvest level for the long term that was much higher • FVS indicated that the dynamic trends of the individual strata may neutralize one another during the transition period to a regulated forest

42. Conclusions • FVS projected that wetter sites are prone to increased mortality in the next two decades • FVS projected higher yields for planting pine & larch vs. natural regen on disease prone sites

43. I do not change the underlying processes of growth, and nature’s grip is tightened on the site where I have worked.-Andy Goldsworthy