RMRS
RMRS
Free selection:
A Silvicultural Option
Russell Graham and
Theresa Jain
USDA Forest Service, Rocky
Mountain Research Station
Moscow, Idaho
RMRS
Beginnings
•
•
•
•
•
•
Silvics
Thinning
Pruning
Harvesting
Planting
Treatments through the
season
• Forest laws
– Forest conversion
– Fire prevention
RMRS
Beginnings
• Evelyn, J. 1664. Sylva: or
a discourse of forest trees
& the propagation of
timber
• Schlich, W. 1904. Manual
of forestry
• Fernow, Bernhard E.
1907. A brief history of
forestry in Europe, the
United States and other
countries
Lewiston, ID 1938
Anaconda, MT1892-smelter fuel
RMRS
Forest Change
Fire Exclusion
RMRS
Fire Excluded Ponderosa Pine
Forests
RMRS
Nutrient/organic matter
compression towards the soil surface
Crowns
Soil surface
Roots/myco/
nutrients
RMRS
Silvicultural Systems
• Since their inception in
the 1800s silvicultural
systems, for the most
part, have been
designed to produce
wood products
• Concepts and
methods in both
even-aged and
uneven-aged systems
can be used to
develop and maintain
forests for a variety
of objectives
RMRS
Management Objectives
Timber
Water & Scenery
Wildfire
Urban Interface
Wildlife
Restoration
RMRS
Desired Forest & Stand
Characteristics (Non-timber)
• Continuous high forest
cover
• Heterogeneous structural
stages, tree densities,
patch sizes, compositions,
tree sizes
• Snags, decadence, down
wood, interlocking crowns
• Fire resilient compositions
and structures
• Over time and space
RMRS
Traditional Selection Systems
Maintain High Forest Cover
• Individual and group
• Age/diameter distribution “q”
• Residual basal area
– Maximum tree size
– Cutting cycle
• Favors tolerant species
• Stand structure homogenized
• Ignores many stand
components
– Snags, decadence, spatial
arrangement
Single Tree Selection-1977
RMRS
180
24 in. tree
120 sq. ft.
160
140
1.5
Trees/Ac
120
100
80
60
1.3
40
20
1.1
0
0
4
8
12
16
Diameter Class (in)
20
24
RMRS
Yarding, and
Weather Damage,
Regeneration
Stand Structures 1996
RMRS
4000
2.8
3500
2.6
Trees/Ac
3000
2500
2.4
2000
1500
2.2
1000
2.0
1.8
500
0
0
4
8
12
16
Diameter Class (in)
20
24
RMRS
Another
Approach for
Maintaining
Diverse Forest
Structures
RMRS
Vegetative Structural Stage
Age
years
Vegetation Classification
1
2
3
4
5
6
7
Reynolds
240
Bormann
120
Carey
250
Spies
1000
Oliver
150
Franklin
1200
0%
20%
40%
60%
80%
100%
Proportion of time spent in each stage
RMRS
•
•
•
•
•
•
Vegetative Structural Stages
(VSS)
Regeneration - 1
Sapling - 2
Young - 3
Mid-aged - 4
Mature - 5
Old - 6
• Interspersion within
and among stands
• Decadence, snags,
woody debris, forest
floor
Growth
RMRS
Structural Stage Distribution Within
Stands and Landscapes
Proportion of Area
Percent (%)
20
20
20
20
10
10
Regeneration Sapling Young Mid-aged Mature Old
0-20 Yrs ~~~ Time Necessary ~~~ 250 + Yrs
RMRS
•
•
•
•
Historical Forest
Structures and
Compositions
Groupy
Patchy
Heterogeneous
Maintained in concert by
– Fire
– Diseases
– Insects
– Weather
RMRS
Free Selection
• Combination of elements
and concepts from
– Even-aged - e.g., encourages
seral species
– Uneven-aged - e.g., cutting
cycle, treating all forest
components
• Based on a “Vision” rather
than
– Qs, target tree size, basal area
RMRS
Vision
• Immediate and future desired stand
and forest conditions (trees, forest
floor, decadence, shrubs, forbs etc.
• Native disturbances
• Silvical characteristics
– Tolerance
– Regeneration
– Development
• Tree cohorts i.e. patchiness, groups
• What is presented
• Prescription highly variable from
location to location within stands and
landscapes
– E.g., Species and tree preference can
change drastically in short (5 to 10 m)
distances
RMRS
Quantification
• VSS
– Distribution
– Ariel
proportion
• Classify 1st
• Describe 2nd
RMRS
Free Selection
Ponderosa Pine Restoration
• Reference conditions
– Pre-European settlement
– Goshawk
– Franklin et al.
•
•
•
•
High social value
Critical stakeholders
Old-growth
Functioning forest
RMRS
Dry Forest Vision
• Functioning forest
– Snags, patches, decadence
• Reduce effects of damaging
wildfire
• Encourage ponderosa pine
regeneration and
development
• Maintain native forest
characteristics
• Decrease forest floor organic
layers
RMRS
Untreated
Size of Tree Groups
RMRS
Southern Idaho
0.120
5
8
0.100
Tree Group Size (Ac)
Number of tree groups /Ac
5
0.080
6
0.060
5
6
7
5
0.040
5
3
2
6
2
3
4
4
3
0.020
0.000
1
5
6
7
8
9
X
-------------Treated Plots--------------------
10
11
12
X
Control Plots
Basal Area Within Groups
RMRS
2000
1800
Basal Area (sq ft/Ac)
1600
1400
1200
1000
800
600
400
200
0
1
2
3
4
5
6
7
8
9
X
-----------------Treated Plots-----------------
10 11
12
X
Control Plots
Stand Basal Area
In and Outside Groups (Free)
RMRS
Group
Free
Basal Area/Ac (Sq Ft)
100
80
60
40
20
0
1
2
3
4
5
6
7
8
9
X
-----------------Treated Plots-------------------------
10
11
12
X
Control Plots
RMRS
Treating
RMRS
Restoring the
Forest Floor
• Snow well burning
• Duff mixing
– Increase aeration and
decomposition
• Soil temperature < 4o C
RMRS
Treated
RMRS
Vertical and Horizontal
Arrangement
• Horizontal
– Group
– Clump
– VSS
interspersion
• Vertical
– Single story
– Multi-story
– Spatially
distributed
– VSS dependent
RMRS
Silvicultural System
• Series of treatments
through the life of a
forest (landscape) to
meet a management
objective
• Documented in a
silvicultural
prescription(s)
RMRS