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SILVICULTURAL CONSIDERATIONS FOR RESTORATION & FUELS TREATMENTS. Objectives. Discuss silvicultural principles related to restoration/fuels treatments Compare conditions from the 1900 Cheesman Lake reconstruction to current project work.
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SILVICULTURAL CONSIDERATIONS FOR RESTORATION & FUELS TREATMENTS
Objectives • Discuss silvicultural principles related to restoration/fuels treatments • Compare conditions from the 1900 Cheesman Lake reconstruction to current project work. • Comments apply to the Stand/Treatment level for 1 treatment entry. • Recommended metrics apply to PSI treatments.
Silviculture Terminology • Regeneration (Reproduction) Method: A cutting method by which a new age class is created. • Stand Improvement: A term comprising all intermediate cuttings made to improve the composition, structure, condition, health, and growth of even- or uneven-aged stands.
Residual Stand Relative Density • Stand Density Index (SDI): Arelative measure of stand density that provides a relationship between stand basal area, trees per unit area, average stand diameter, and stocking of a forested stand (Reineke 1933). • The index is not influenced by age or site quality.
Stages of Stand Development 25% RD 35% RD 60% RD Source: Oliver and Larson, 1990
Recommended Stocking Levels:Black Hills Ponderosa Pine Gringrichstocking curves for ponderosa pine in the Forest Service’s Rocky Mountain Region (R2) (Forest Service Manual, R2 Supplement 2409.17-92-2 1992)
Ponderosa Pine Regeneration Study Long term study of ponderosa pine seedfall, natural regeneration, and seedling growth, 1981-2001, Manitou Experimental Forest Results: • Good seed crops produced every 4-6 years. • Predation by animals resulted in on 14% of total seedfall available for germination. • ShelterwoodOverstories between 25-60 BA over scarified seedbeds provided optimal conditions for natural seedling establishment. Shepperd et al. 2006
Black Hills Annual AvgPrecip & Temp Rocky Mts & Southwest USDA Forest Service General Technical Report RMRS-GTR-97. 2002
Cheesman Lake Study • Density, structure, and species composition is highly variable by aspect. • Reconstructed stocking levels may be low due to: • Many of these plots burned severely in 1851. • Mortality of pre 1900 trees was not factored in.
Cheesman Lake Study • Riparian plot, 77 trees/ac, 57 BA
Cheesman Lake Study • South plot, 65 trees/ac, 1 BA
Cheesman Lake Study • Ridgetop plot, 32 trees/ac, 19 BA
Cheesman Lake Study • West plot, 20 trees/ac, 5 BA
Cheesman Lake Study • North plot, 166 trees/ac, 36 BA
Phantom Creek 2 • Average Residual Basal Area = 60 sq. ft.
Phantom Creek 2 • Ponderosa pine stand, 46 trees/ac, 50 BA
Phantom Creek 2 • Mixed conifer stand, 73 trees/ac, 70 BA
Projected Metric Ranges: PSI Ponderosa Pine Stands
Projected Metric Ranges: PSI Mixed Conifer: Ponderosa Pine/Douglas-fir
Comparison with Cheesman Data Projected BA Distribution
Comparison with Cheesman Data Projected CBH = 20-36
Comparison with Cheesman Data Projected CBD = 0.019-0.046
SUMMARY • Treatments will result in a high level of variability for residual stand conditions within treatment areas. (density, structure, species composition, size classes) • Natural regeneration will occur at lower stand densities • Restoration ecology research should identify the target trend and range but may not be appropriate to assess precise post treatment conditions. • Target ranges must be wide enough to capture variation of major cover types in treatment areas: • For example: 40-80 sq. ft. of BA.