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Stream Protection Zone (SPZ)

Harvesting in and Around SPZ's

Consider the following practices when harvesting timber in and around the Stream Protection Zone.

The SPZ is not a "No logging" zone. But because of its values, timber harvesting from SPZ's should be done with special care.

Trees are important to a healthy SPZ.
  • Leave 75 percent of the existing shade adjacent to streams; hardwoods, un-merchantable, conifers and shrubs.
  • Protect SPZ's
  • Maintain sufficient ground cover to trap sediment.
  • This vegetation is the filter that keeps sediment from reaching the stream. If it gets torn up during harvesting, it cannot do the job. Skidders and tractors must stay out of SPZ's.
    Harvesting in the SPZ
  • Use directional falling for harvest operations in the SPZ or wetlands. Avoid falling trees in streams or water bodies. Limb or top trees above the high water mark.
  • Consider hand scalping and planting within the SPZ.
  • Especially important are stream bank trees and shrubs. They anchor the bank, shade the stream, provide food, supply cover for fish, and habitat for birds and other wildlife.
    Directional failing and/ or mechanical feller-bunchers allow removal of some SPZ trees without damaging the SPZ. Never operate equipment on stream banks or in wetlands. It can damage the fragile SPZ. Eventually, bank trees fall across the stream, helping to create a stair step of pools in the stream channel, providing an essential fish habitat component. The larger the bank trees, the better.

    Leave snags, and defective and sub-merchantable trees in SPZ's. They are habitat for many birds and animals. Keep slash out of water bodies by removing limbs and tops well above the stream high-water mark. Rotting slash uses up oxygen, robbing it from fish and other aquatic animals.
  • Equipment is not allowed in SPZ's or wet areas.
  • Suspend the lead end of the log during skidding whenever possible. Logs should be fully suspended when skyline skidding across a stream and immediately above streambanks. Avoid ground skidding in wet areas.
  • Whole-tree or tree length yarding can reduce the need for slash disposal in the SPZ.
  • Site preparation near SPZ's
  • Steep slopes containing material that could roll down-slope and fall into a stream during burning should receive special attention.
  • Protect the SPZ with a slash free strip within the SPZ by whole tree harvesting.
  • Retain trees necessary for bank stabilization and as a future source of large woody debris to the stream channel.


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