FVS Regeneration Imputation Don Vandendriesche USDA Forest Service Forest Management Service Center Growth and Yield Group

- Regeneration Imputation To impute implies the assignment of something to another. The process calls for querying existing data sets for representative stand types and tabulating their seedling/sapling component.

- Regeneration Questions  Relative to stand conditions … Quantity ~ Seedling Count? Quality ~ Species Composition?

Regeneration Imputation Methods Colville-Okanogan-Wenatchee National Forests

- Spatial Data: 5.6 million acres

- Inventory Data: CVS

Topics I.Ground Rules II.Pattern Revelation III.Repute the Program IV.Prorating Multipliers V.West vs. East

I. Ground Rules Established seedlings generally have an acceptable minimum girth and height that indicates having a root system firmly entrenched in mineral soil. Vegetation states are described as a composite of size and density classes. Size is based on QMD. Density is based on canopy cover.

- Ground Rules Tally 2” saplings - {1” – 3” diameter, ~ 10’ height} Bracket Tally by 5” size class - {0-5”, 5-10”, 10-15”, 15-20”, 20-25”} Bracket Tally by 30% canopy cover - {10-40%, 40-70%, 70%+}

II. Pattern Revelation: “½ - Rule”

- Pattern Revelation: “½ - Rule”

III. REPUTE the Program REPUTE embodies the concept of Regeneration Imputation. REPUTE reads the ‘Stand Table’ output files from the FVSSTAND program to develop regeneration keyword component files.

Grand fir TREES AVG AVG /AC DBH HGT DIA. CLASS 2.

Natural 0 Parms(GF, & ((30.095*_SAPX)* &

IV. Prorating Multipliers The REPUTE program produces an average representation of the strata. This condition depicts the average size and density class. Proportioning the 2” saplings by size/density class based on shade tolerance renders multiplicative factors that can be used in conjunction with REPUTE.

Colville-Okanogan-Wenatchee Plot Distribution

Different species that have a higher tolerance to shade soon become established beneath the pioneers. - Shade Tolerance Intolerant: Western larch Lodgepole pine Ponderosa pine Mid-Tolerant: Western white pine Douglas-fir Tolerant: Grand fir Subalpine fir Engelmann spruce Pacific silver fir Western Redcedar

- Size Class Multipliers

- Canopy Cover Multipliers

- Trial Results: Intolerants

- Trial Results: Mid Tolerants

- Trial Results: Tolerants

- Trial Results: All Shade Tolerances

V. West vs. East Mark Twain National Forest

- Spatial Data: 1.5 million acres

- Inventory Data: FIA

Mark Twain Plot Distribution

- Pattern Revelation: “½ - Rule”

New Regeneration Paradigm

"move towards a full regeneration establishment model for all variants"

Questions?