Forest Management Impacts

1
Forest Management Impacts

• Natural forest environments have low erosion.
• Forest management can significantly accelerate
  erosion.
• Felling trees little impact
• Moving trees in harvest area moderate impact
• Different harvest systems (animal - helicopter)
• Preparing site for regeneration high impact
• Roads high impact
• High erosion rates are short lived from a logged
  area, but can be long-term from roads.
• Mass soil movement can be an issue in mountain
  environments.

2
Washington State - 2007

• Clearcut
• Steep Slopes
• Mud Slides

3
Forestry BMPs
Erosion and Sedimentation is a Nonpoint Source
Pollutant (NSP)   The application of Best
Management Practices (BMPs) is the typical
management/regulator method for addressing
NSP. In some states bonds are posted for the
successful implementation of a BMP or treatment,
which are monitored by state agents.  
4
Forestry BMP Practices
1. Identify areas and times of concern. The
best BMP is based on site conditions. Mapping
required. Wet Seasons Greater concerns
Streamside areas Steep Slopes  2. Exclusion
Management activities banned in different
areas   Roads and clearcutting banned in
riparian areas and landslide zones
5
Forestry BMP Practices
3. Logging Methods Tractor - lt 15
slopes Different types of tractors for soil
conditions Cable - gt 15 slopes, logging
uphill Balloon - gt15, logging downhill
Helicopter non-roaded areas Logging Designs
Planning trails for removing timber to
minimize impact area
6
Wider tires and duals increase the soil contact
area and increase traction and flotation on moist
and wet soils.
7
Logging Equipment Impacts
8
Uphill Logging
Skyline Cable System
Highline Cable System
Increase soil exposure
9
(No Transcript)
10
No dragging trees on ground decrease rutting
11
(No Transcript)
12
Figure 3. Parallel trail design Figure 4.
Herringbone trail design Figure 5.
Dendritic trail design
The maximum impact occurs the first time you
drive over an area design the logging system to
minimize the impact area.
13
Logging Uphill
14
Forestry BMP Practices
4. Seasonal Constraints   Wet Season Fine
textured soils high potential for
compaction Winter logging
is common is many parts of the country 5.
Site Preparation higher impact then cutting
trees. Highly erodible sites should not be
prescribed burned Intensive site preparation
should always follow contour of land Do
not conduct mechanical site preparation in SCZs
15
Site Preparation

• Fire
• Prescribe burns to remove litter and competition.
  
• Creates bare soil
• Chemical
• To decrease competition
• Can create base soil, but not as bad a fire
• Mechanical the worst
• Plowing
• Chopping
• Shearing
• Ripping
• Bedding

16
Site Preparation
17
(No Transcript)
18
(No Transcript)
19
Forestry BMP Practices
6. Streamside Conservation Zones (Buffer
Strips) Filter Pollutants (surface and
subsurface) Stream Bank Stability Shade
(temperature control) Keeps Equipment Out of
Stream Habitat
20
Forestry BMP Practices
7. Roads are the primary source of sediment from
forests. Minimize road area, designed road
system, planning Restoration of Roads Road
Surface Treatments (Rock, Asphalt) Control
Drainage Dirt roads have zero infiltration -
Water Bars Treat or Remove Road Fills.
21
(No Transcript)
22
More cost effective
Fill is very erodable, the less fill the better.
Better for erosion, but very costly, cut material
must be removed.
23
(No Transcript)
24
Forestry BMP Practices
7. Enforcement Logging Plans Prepared by a
Certified Forester Bonding Monitoring