PRINCE GEORGE FOREST DISTRICT
DISTRICT MANAGER POLICY		 SUBJECT:
Management of Small Fish-streams (S4)
Ministry of
Forests and Range

SECTION I

Policy for Maintaining the Biological and Physical Attributes of S4, Small Fish-bearing Streams

This policy sets out five objectives that should be recognized to address the biological and physical habitat requirements of small fish-bearing streams (S4).  These objectives will guide the statutory decision maker in making a determination to approve an operational plan with respect to the management of S4 streams.  By setting out these objectives and the companion guidelines document, it is anticipated that prescribing foresters and reviewing foresters will be able to prepare and review prescriptions and plans while knowing the statutory decision maker’s expectations.  This document presents the key elements that should be considered and evaluated in any prescription or plan.

PURPOSE:

The purpose of this policy is to communicate the guiding principles that the district manager will use to structure his thought processes when making a statutory decision with respect to Section 41(1) of the Forest Practices Code of British Columbia Act.

AUTHORITY REFERENCES:

  • Section 41 (1) of the Forest Practices Code of British Columbia Act
  • Sections 39 (4)(a)(ii), (4)(b), (5)(a), and (5)(b) of the Operational Planning Regulation
  • Section 37 (1)(f) of the Operational Planning Regulation
  • Sections 59 and 60 of the Operational Planning Regulation
  • Fisheries Act, Canada
  • Riparian Management Area Guidebook
  • Fish-stream Identification Guidebook, Second Edition
  • Pierre Beaudry’s report, Riparian Management of S4 Streams in the Prince George Forest District April 1999)
PRINCIPLES:

Issue Definition:

These objectives are meant to describe the biological and physical habitat requirements of small fish-streams, and are based as much as possible on current scientific literature.  It is expected that individual prescriptions will include site specific strategies designed to achieve these objectives and reflect local site and stand conditions.

Policy Decision:

Section 37 (1)(f) of the Operational Planning Regulation requires that a riparian assessment to determine the riparian class of streams must be available before a silviculture prescription may be approved.

Section 39 (4)(a)(ii) of the Operational Planning Regulation requires that for the area under a silviculture prescription and the area adjacent to that area, that the prescription contain a map that illustrates all streams and their riparian class.

Section 39 (4)(b) of the Operational Planning Regulation requires that for the area under a silviculture prescription and the area adjacent to that area, that the prescription describe and contain for each stream a reserve zone, where applicable, and a riparian management zone (RMZ), including a description of the residual basal area or stems per hectare to be retained within.

Section 39 (5) of the Operational Planning Regulation requires that the silviculture prescription addresses harvesting within riparian management areas (RMA).  The prescription specifically has to address cross-stream yarding, debris management, stream bank protection, and maintaining shade for known temperature sensitive streams.

Guiding Principles for Management of S4 Streams:

Stream Classification:

A small stream classified as a fish-stream (S4) must be managed as a fish-bearing stream regardless of the method used to classify it.  The licensee always has the option of classifying a stream in accordance with the Fish-stream Identification Guidebook, if they feel that default classification is in error.  Note:  Local area agreements, when developed, may also affect the classification of these streams.

It is inappropriate to classify a stream as S4, simply to avoid the process of stream classification, and then to manage the stream as though it were non-fish-bearing.  The practice of “defaulting” all small streams to S4 results in an unnecessary expenditure when providing for fish passage at creek crossings and may necessitate different riparian management practices.

A reach should be assessed for fish presence, and a classification made as to whether it is a S4 or S6 stream.  The results of such an inventory can be applied immediately to a silviculture prescription or a road permit design.  It is not necessary to have the inventory approved by a government agency prior to its’ use, but the inventory may be subject to a review to ensure that it was undertaken in accordance with the Fish‑stream Identification Guidebook.

Riparian Management Objectives for S4 Stream RMZs:

Objective #1:

Maintain 50 to 75 percent of the natural levels of shading and light intensity reaching the stream surface and forest floor.

  • Shading as assessed using the concept of angular canopy density (Pierre Beaudry’s report, Riparian Management of S4 Streams in the Prince George Forest District (April 1999)).

Objective #2:

Maintain an adequate long and short-term supply of large woody debris (LWD) in the stream channel.

Definitions:

  • Short-term:  the 50 years immediately following forest harvesting.
  • Long-term:  the period between 50 and 150 years after forest harvesting.  During this period a “new forest” will replace the harvested forest.

Detailed definitions of adequate and LWD are provided in Pierre Beaudry’s report, Riparian Management of S4 Streams in the Prince George Forest District (April 1999).

Objective #3:

Maintain natural root structure adjacent to streams with particular emphasis on minimizing soil disturbance within 5 metres of the stream channel.

Objective #4:

Do not overload the stream with an excessive supply of fine organic debris (FOD).

Definitions:

  • FOD:  Branches and other fine logging slash.
  • An excessive supply is an amount sufficient to alter or divert the stream flow.

Objective #5:

Concentrate retention (both patch and single tree) in the most critical portion of the RMZ, that is the 10–15 metres closest to the stream.

SECTION II

Guidelines to Assist Prescribing Foresters in Developing Management Strategies Which Will Achieve the Desired Management Objectives for S4 Streams

SCOPE:

This district manager’s guideline provides recommendations to prescribing foresters on how they may achieve the management objectives described in the District Manager Policy for riparian management of S4 streams.  It provides a body of information that will guide the statutory decision maker in making a determination to approve a silviculture prescription with respect to the management of the biological and physical habitat requirements of a small fish-stream (S4).

PURPOSE:

The purpose of this guideline is to communicate the district manager's expectations with respect to best practices that could be employed to manage S4 streams.  The strategies outlined in this document will be considered by the statutory decision maker when making a determination to approve an operational plan under Section 41 (1) of the Forest Practices Code of British Columbia Act.

AUTHORITY REFERENCES:

  • Section 41 (1) of the Forest Practices Code of British Columbia Act
  • Sections 39 (4)(a)(ii), (4)(b), (5)(a), and (5)(b) of the Operational Planning Regulation
  • Section 37 (1)(f) of the Operational Planning Regulation
  • Sections 59 and 60 of the Operational Planning Regulation
  • Fisheries Act, Canada
  • Riparian Management Area Guidebook
  • Fish-stream Identification Guidebook, Second Edition
  • Pierre Beaudry’s Report, Riparian Management of S4 Streams in the Prince George Forest District April 1999

PRINCIPLES:

Issue Definition:

This document describes examples of strategies that could be employed to achieve the objective of maintaining biological and physical habitat requirements of small fish-streams, and are based as much as possible on current scientific literature.  It is expected that individual prescriptions will include site specific strategies that reflect local site and stand conditions.

Policy Decision:

Section 39 (4)(b) of the Operational Planning Regulation requires that for the area under a silviculture prescription and the area adjacent to that area, that the prescription describe and contain for each stream a reserve zone, where applicable, and a RMZ including a description of the residual basal area or stems per hectare to be retained within it.

Section 39 (5) of the Operational Planning Regulation requires that the silviculture prescription addresses harvesting within RMAs.  The prescription specifically has to address cross-stream yarding, debris management, stream bank protection, and maintaining shade for known temperature sensitive streams.

Strategies for Management of S4 Streams:

Points to Consider when Developing Site Specific Strategies:

  • The prescription must describe and contain for each S4 stream, a RMZ including a description of the residual basal area or stems per hectare to be retained within.
  • Large deciduous trees can be utilized to supply short-term LWD.
  • Retention for LWD recruitment should target stems greater than 15 centimetres diameter at breast height (dbh).  These trees should be positioned such that they will have a good probability of eventually falling across the stream channel.
  • Basal area retention or stems per hectare retention do not need to cover the entire RMA, but rather cover an area large enough to achieve the desired objectives.
  • The shape and size of retention patches should not be dictated by the RMA width, but rather the need to create a patch that is as windfirm as possible considering the timber type, stand structure, and topography.  These patches may fill the role of wildlife tree patches.
  • The natural brushy margins and deciduous cover along many S4 streams may be sufficient to achieve the shading objective.  Where insufficient, additional retention may be required to meet the 50 to 75 percent shading objective.
  • The slope and aspect of the block and the relative location of the stream within the block may be sufficient to meet most of shading requirements for the stream.

Examples of Strategies Which May Be Employed to Meet Management Objectives for S4 Streams:

Note:  The examples do not preclude a prescribing forester from proposing alternatives that achieve the desired result, which is to protect the integrity of the stream and stream habitat.

These strategies take into account the stand structure of the forest through which the stream flows.

Examples of Strategies That Could Be Employed to Meet
the Riparian Management Objectives for S4 Streams
in the Prince George Forest District

Stand Structure Example Prescription to meet management objectives
Single Storied
  • The RMZ, within the cut-block, should be managed by leaving undisturbed windfirm residual tree patches (preferred option) and dispersed leave trees along the length of the stream.  Riparian shrub or deciduous vegetation along many streams may provide adequate cover to achieve Objective #1.
  • When shade effective riparian vegetation is not present, patches should be retained which cover at least 40 percent of the channel and, where possible, be at least 150 metres in length.
  • Where shrubs or deciduous cover provides shading or the RMZ is being clearcut, LWD recruitment still needs to be accommodated by leaving 10 to 12 overstory trees per 100 metres of stream length to provide “short-term” LWD (evenly distributed).
  • The residual patches may also serve as wildlife tree patches. It is assumed that the residual patches will serve to meet the shade requirements.  The residual patches will also provide the “long-term” supply of LWD.

Two-Storied
(overstory and intermediate crown class only, no understory)

 Release intermediate layer if of adequate stocking and quality.  The intermediate layer and shrub layer will provide shade and control light intensities, while providing for the long-term supply of LWD.  A minimum of 10 overstory trees per 100 metres of stream length should be retained to provide a supply of short-term LWD.  These residual trees should be positioned such that they will have a good probability of eventually falling across the stream channel and should be greater than 15 centimetres dbh.
Multi-storied 25 to 35 percent of the basal area should be retained.  If this objective can be met by leaving only trees in the intermediate class, then the removal of the overstory is acceptable.  Advance growth in the understory should be protected, as it will be the source of the long-term supply of LWD.  If the intermediate class does not provide 30 percent of the basal area, then 5 to 10 overstory trees per 100 metres of channel length should be left to provide for the short-term supply of LWD.

Natural Shelter-wood
(overstory and advanced regeneration, no intermediates)

 Remove the overstory, but leave 10 overstory trees per 100 metres of stream length harvested.  Protect the advance regeneration during harvest.  This will provide the long-term supply of LWD to the stream channel and the inputs of terrestrial detritus to the aquatic ecosystem, especially if the shrub layer is minimal.

Irregular
(open overstory with abundant understory)

 Release the intermediate and/or understory crown classes if either has adequate stocking and quality.  Leave 8 to 10 overstory (C1) and intermediate (C2) trees per 100 metres of stream channel logged, evenly distributed along the length of the channel.  Choose trees leaning towards the channel when possible.  Advance regeneration must be protected.

____________________________

T. P. (Phil) Zacharatos, R.P.F.
            District Manager