Use of FVS for a Forest-wide Inventory SPOKANE INDIAN RESERVATION

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

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

Comparison of Measurements: Stocking per acre

Volumes Are 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)

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)

Trends in Mortality as It Impacts Net Growth

Stand Age Conditions

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

Inventory Strata Spokane Indian Reservation

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

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

Austrian Formula No target future volume used GrossNet Yr 2045VolumePer acre StratumNet Analysis StratumI measI projV measVpredAdjustAAC AcresAAC (bf/ac/yr) (bf/ac) (bf/ac/yr) (MBF/yr) Dry Pine , ,9581,671.1 Pine-fir , ,7906,354.1 Ninebark , ,9153,667.3 Wet Grand fir , ,6854,600.1 Sum of All Strata 103,348 16,293

Area-Volume Control Check Method Summary of results

FVS Projections

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?

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)

Stratum summary data Dry PinePine-firNinebarkWet Grand fir Habitat TypesPipo/StcoPipo/SyalPsme/PhmaPsme/Vaca Pipo/AgspPsme/SyalAbgr/PhmaAbgr/Libo Pipo/FeidPsme/Caru Abgr/Clun Pipo/Putr Thpl/Clun FVS HabTypes , 310, , 520, 530 Number of Plots 92 GF / 68 LP Commercial26,95441,78816,914GF: 10,169 Forest Acres LP: 7,517

FVS Base Parameters by Stratum Dry PinePine-firNinebarkWet Grand fir Species Preferences PP: -2.0 DF: +1.0WL: -3.0WL:-2.0WL:-3.0 DF: +1.0 DF:+2.0 LP: +3.0LP:+4.0LP: 0 GF:+8.0GF:+6.0 READCORDPP: 0.367PP: 0.519PP: 0.651PP: DF: 0.714WL: 1.084WL: 0.853WL: DF: 0.946DF: 0.966DF: LP: 0.566LP: 0.551LP: GF: 0.793GF: Maximum BA from 1998 CFI BAMAX used MORTMULTPP: 0.55PP: 1.17PP: 1.25PP: usedWL: 0.35 WL: 0.73WL: DF: 0.79DF: 0.41DF: 0.51DF: LP: 1.24LP: 0.74LP: GF: 2.00 GF: 1.454

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

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

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

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

Results of FVS Projections

Projected changes in board-foot stocking Dry Pine Stratum

Projected changes in board-foot stocking Pine-fir Stratum

Projected changes in board-foot stockin Ninebark Stratum

Projected changes in board-foot stocking Wet Grand fir Stratum

Projected changes in board-foot stocking Lodgepole Stratum

Projected changes in board-foot stocking All strata

Harvest trends for all strata

Projected changes in harvest yields All strata

Projected changes in mortality Dry Pine stratum

Projected changes in mortality Pine-fir stratum

Projected changes in mortality Ninebark stratum

Projected changes in mortality Wet Grand Fir stratum

Projected changes in mortality Lodgepole stratum

Projected changes in mortality All strata

Comparison of Methods

Overview of the results MethodAAC (MBF) Austrian, high target future volume11,574 Austrian, mid target future volume13,573 Austrian, future volume unchanged16,072 Area-volume Check15,163 FVS, 20-yr average yield15,368 FVS, 100-yr average yield, Opt. 116,797 FVS, 100-yr average yield, Opt. 217,527

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

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

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