Download Silvicultural Considerations for Restoration and Fuels Treatment



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.
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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.
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
Stand Density Index (SDI):
A relative 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.
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25% RD
35% RD
60% RD
Source: Oliver and Larson, 1990
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Gringrich stocking curves for ponderosa pine in the Forest
Service’s Rocky Mountain Region (R2) (Forest Service Manual, R2
Supplement 2409.17-92-2 1992)
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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.
◦ Shelterwood Overstories
between 25-60 BA over
scarified seedbeds provided
optimal conditions for natural
seedling establishment.
Shepperd et al. 2006
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Black Hills
Rocky Mts & Southwest
USDA Forest Service General Technical
Report RMRS-GTR-97. 2002
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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.
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Riparian plot, 77 trees/ac, 57 BA
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South plot, 65 trees/ac, 1 BA
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Ridgetop plot, 32 trees/ac, 19 BA
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West plot, 20 trees/ac, 5 BA
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North plot, 166 trees/ac, 36 BA
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Average Residual Basal Area = 60 sq. ft.
COVER TYPE
RESIDUAL BA
% PROJECT AREA
Aspen
20
5
Ponderosa Pine
50
40-50
Mixed Conifer
70
30-40
Douglas-fir
90
10-15
No Treatment
<1%
Spruce
15
16
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Ponderosa pine stand, 46 trees/ac, 50 BA
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Mixed conifer stand, 73 trees/ac, 70 BA
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Ponderosa Pine Stands
METRIC
LOW
HIGH
TPA (> 1.0 " dbh)
30
80
BA (sq. ft.)
40
60
% PP - Overstory (BA)
90
100
% DF - Overstory (BA)
0
10
15
25
0.015
0.035
25
35
CC (%)
CBD (kg/m¯³)
CBH (feet)
Age Classes
Existing
Understory Species %: TPA-seedlings
Existing
Understory Species %: Shrubs, Forbs, Grasses
Existing
Noxious Weeds/Exotics
Presence of
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Mixed Conifer: Ponderosa Pine/Douglas-fir
METRIC
LOW
HIGH
TPA (> 1.0 " dbh)
50
160
BA (sq. ft.)
60
80
% PP - Overstory (BA)
65
100
% DF - Overstory (BA)
0
35
15
25
0.035
0.05
15
30
CC (%)
CBD (kg/m¯³)
CBH (feet)
Age Classes
Existing
Understory Species %: TPA-seedlings
Existing
Understory Species %: Shrubs, Forbs, Grasses
Existing
Noxious Weeds/Exotics
Presence of
20
Cheesman Basal Area (1900)
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Frequency
10
Projected BA
Distribution
8
6
4
2
0
0
10
20
30
40
50
60
70
80
90
Basal area (ft2/acre)
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Canopy base height (circa 1900)
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Projected
CBH =
20-36
30
feet
20
10
0
0
1
2
X Data
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Canopy bulk density (circa 1900)
0.035
Projected CBD =
0.019-0.046
0.030
kg m
-3
0.025
0.020
0.015
0.010
0.005
0.000
0
1
2
X Data
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
Treatments will result in a high level of variability for
residual stand conditions within treatment areas.
(density, structure, species composition, size classes)
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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.
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