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Logging in the vicinity of streams
This web article explains
how loggers and landowners can harvest selected timber near streams
while minimizing sediment runoff and protecting the stream during
a timber harvest.
Timber harvesting should be avoided or well-controlled near streams
of all sizes, to preserve a "streamsize management zone."
In the Finger Lakes, most streams enter one of the major lakes
after a short distance. Logging can have a profound effect on
the quality of drinking water, wildlife habitat, and stream health.
A special zone exists
around the edges of creeks and shores of ponds or lakes. This
zone, from 50 to 100 feet wide, affects what kind of timber management
is appropriate. Many people in the forestry industry know these
as Streamside Management Zones.
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At a timber
harvest, Streamside Management Zones help:
- Filter
sediment and nutrients from runoff. As runoff water
moves through plants and the duff layer (needles, leaves
and decaying matter), it slows and drops sediment that
has been carried along. This settling process keeps sediment
and nutrients from flowing into streams and lakes. It
also allows plant roots to take up the nutrients that
have dissolved in the runoff and soaked into the soil,
further reducing the amount of pollution flowing into
lakes and streams.
- Allow water
to soak into the ground. Trees and plants, leaves
and twigs slow surface runoff, allowing the water to soak
into the soil. This helps to reduce peakflow levels in
streams and replenishes the groundwater that helps maintain
lake levels and stream flows.
- Stabilize
streambanks and lakeshores. Trees and plants along
streambanks and lakeshores can reduce soil erosion because
their roots hold the soil together, making it more difficult
for waves, currents and runoff to wash the soil away.
Plants also reduce the impact of raindrops on
exposed soil, decreasing erosion.
- Shade streams.
In most cases, plants and trees along streambanks are
necessary to shade streams, keeping the water from becoming
too warm for aquatic life in the summer.
- Provide
food and habitat for aquatic organisms. Fallen leaves
and other organic debris from trees are the base of the
food chain for aquatic organisms in small forest streams.
Large woody debris (large fallen logs, generally at least
12 inches in diameter with an anchored root ball) create
riffle areas and plunge pools, critical habitat for fish
and other aquatic organisms. The pools trap leaves and
twigs long enough for microorganisms to decompose them.
These microorganisms become food for insects and other
invertebrates, which in turn become food for fish.
Wisconsin
Department of Natural Resources. 1995. Wisconsin's Forestry
Best Management Practices for Water Quality. Publication
number FR093.
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Best Management
Practices when logging near streams
Identify the location
of streams and adjacent areas.
During a walk-through
or meeting with a forester or logging crew, take a few minutes
to physically identify these special management areas around streams.
Use surveyor's flagging if appropriate to mark the boundary of
any streamside areas where special care is needed. For example,
if the stream course can not be seen due to slope or vegetation,
the flagging will make it easier for a busy logging crew to avoid
coming too close to a stream. Flagging is a form of communication
between logging workers, foresters, and landowners.
Landowners are partly
responsible for ensuring logging activities do not cause environmental
harm to streams and lake waters.
Plan roads, skid
trails, and landings to avoid streamside zones.
Using your maps
and knowledge of the site, refrain from making roads or log landings
within the special streamside zones. This is an important area
to avoid soil compaction. Of course, stream crossings are constructed
to allow roads to pass through streamside zones.
More
about crossing streams with logging equipment . . . 
Maintain a wide
strip of intact trees, seedlings and shrubs on either side of
a stream.
More vegetation
in streamside zones is better. Some merchantable and cull trees
may be removed, but a significant amount of timber should remain
standing. Advise your forester to plan for at least 60 square
feet of basal area per acre along the edges of streams.
Do not allow machinery
to enter steep gullies.
In almost every
gully in the Finger Lakes region, the streamside zone extends
far up the sides. Large logging machinery should not be operated
on this terrain. To extract timber from these areas, use winches
or small-scale equipment, like ATV logging devices. Drag logs
cross slope and immediately repair or divert water from tracks.
In most cases, large trees in gullies are essential for keeping
the soil intact and should not be harvested at all. Remember,
landowners are partly responsible for ensuring logging activities
do not cause environmental harm to streams and lake waters.
Use directional
felling techniques to keep treetops away from streams.
Loggers should be able to direct the fall of trees being harvested.
Treetops can clog stream courses, causing unexpected flooding
and new erosion. Some large woody debris in streams is acceptable,
even beneficial, for fish and insect habitats. However, the amount
of small branches and limbs should be minimized to prevent flooding.
Keep skidding equipment
50 feet or more from stream banks (100 feet or more on sloping
terrain.)
Keep fuels and other
chemicals out of the streamside zone.
Each logging job, even weekend projects, should have a special
protected area for refueling equipment. Gasoline, oil, hydraulic
fluids, and pesticides often spill or leak unexpectedly. These
mishaps can have tragic consequences for the wildlife and ecology
of streams. Make sure such materials are contained, stored and
transported safely, always outside the streamside zone.
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