Silvicultural Systems
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Transcript Silvicultural Systems
FOREST MANAGEMENT SYSTEMS
“It is a certainty that demands on the
world’s forest lands will become greater
while the area available for forest
production will decrease …
The question facing us is not whether to
use the forest resource but how to use it
wisely for the greatest benefit to man in
the long term.”
-Bruce Zobel, 1978
FIVE ERRONEOUS BELIEFS ABOUT
FORESTS & FOREST MANAGEMENT
1. Ecosystems are inherently stable if people
would simply leave them alone.
2. Diversity and stability are closely linked.
3. Evolution has finely tuned ecosystems, with
genotypes perfectly matched to their site of
origin. Therefore, all genetic diversity is
important and should be preserved.
4. Any manipulation of the forest results in a
severe loss of diversity.
5. “Natural” is always “best”.
- L. Fins, 1993, Forest Geneticist
SILVICULTURE
“The art and science of reproducing and
growing trees and forests in a sustainable
manner based on principles of forest ecology
for the benefit of society.”
SILVICULTURAL SYSTEMS
A silvicultural system is a series of forestry
practices using natural strategies designed to
regenerate specific forest types according to
landowner objectives.
Even-aged vs. Uneven-aged
Clearcutting
Shelterwood
Selection
Intermediate Treatments
Artificial Regeneration
NATURAL REGENERATION
Most of our forests in the U.P. are regenerated
using natural strategies in silvicultural systems.
Planting is
Sprouts
Seeds
not
necessary.
Suckers
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 30.
Layering
CLEARCUTTING
An even-aged system where all or
nearly all of the trees are harvested
at one time.
Clearcut
Seed-Tree
Forest Types: Pines, Spruces, Aspen, Oaks
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 34-35.
SHELTERWOOD
An even-aged system where one or two cuts are used
prior to the final harvest. The first two cuts stimulate
and establish advanced regeneration before the final
harvest cut.
Uniform
Group
Strip
Final Crop Should Be:
• Windfirm
• Non-Epicormic
• Good Seeders
• Undamaged by Logging
Forest Types: Northern Hardwoods,
Spruce-Fir, White Pine, Oak, Paper Birch
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 36.
SELECTION
An uneven-aged system where trees of all sizes are
harvested on a cycle of about 10-15 years.
A selection harvest IS NOT a diameter-limit cut!
Single-Tree
Group
Forest Types: Northern Hardwoods,
Spruce-Fir, Black Ash on Good Sites
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 37.
HARVEST SYSTEM
CONTRAST
Clearcut
Factors
Selection
Low
Shade Tolerance
High
Early
Succession Stage
Late
Lowest
Harvest Cost
Highest
Irregular
Revenue Flow
Steady
Good
Game Habitat
Poor-Medium
Poor
Visual Quality
High
High
Disturbance
Low
INTERMEDIATE
TREATMENTS
Nearly any forestry practice not connected
with regeneration or harvest can be
considered an intermediate treatment.
Timber Stand Improvement (TSI)
Weeding, Cleaning, & Release
Salvage & Sanitation Cutting
Protection
Pruning
TIMBER STAND IMPROVEMENT
TSI thinnings are intended to improve the quality
of a timber stand. They can be commercial or
non-commercial.
Low
Fork
Crooked
Unwanted
Limby Crowded Species
Before TSI
After TSI
Adapted from Baughman, et al., 1993
.Woodland Stewardship. P. 41.
ARTIFICIAL
REGENERATION
We usually think only of the physical act
of planting trees, but there is much more
to consider in order to achieve success.
Species Selection
Site Selection
Site Preparation
Planting Methods
Competition Control
Direct Seeding
Underplanting
TREE PLANTING
“Bare-root” stock must be handled
carefully. Open root exposure can kill a
seedling in under five minutes.
Planting
Heeling
1
1
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 32-33.
2
3
2
4
5
3
6
7
4
CROP TREE RELEASE
The idea is to
allow the better
quality trees more
crown room, which
translates to
faster DBH
growth and value.
Adapted from Baughman, et al., 1993. Woodland Stewardship. P. 42.
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After
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