Washington Administrative Code › Title 222 - Forest Practices Board › Chapter 222-30 - Timber harvesting › Section 222-30-021 - *Western Washington riparian management zones

Current through Register Vol. 24-14, July 15, 2024
These rules apply to all typed waters on forest land in
				Western Washington, except as provided in WAC
				222-30-023. RMZs are measured
				horizontally from the outer edge of the bankfull width or channel migration
				zone, whichever is greater, and extend to the limits as described in this
				section. See board manual section 7 for riparian design and layout
				guidelines.
(1)
Western
			 Washington RMZs for Type S and F Waters
have three zones: The core zone
			 is nearest to the water, the inner zone is the middle zone, and the outer zone
			 is furthest from the water. (See definitions in WAC
			 222-16-010.) RMZ dimensions vary
			 depending on the site class of the land, the management harvest option, and the
			 bankfull width of the stream. See tables for management options 1 and 2 below.
None of the limitations on harvest in each of the three zones
				listed below will preclude or limit the construction and maintenance of roads
				for the purpose of crossing streams in WAC
				222-24-030 and
				222-24-050, or the creation and
				use of yarding corridors in WAC
				222-30-060(1).
The shade requirements in WAC
				222-30-040 must be met regardless
				of harvest opportunities provided in the inner zone RMZ rules. See board manual
				section 1.
(a)
Core
			 zones.
No timber harvest or construction is allowed in the core zone
			 except operations related to forest roads as detailed in subsection (1) of this
			 section. Any trees cut for or damaged by yarding corridors in the core zone
			 must be left on the site. Any trees cut as a result of road construction to
			 cross a stream may be removed from the site, unless used as part of a large
			 woody debris placement strategy or as needed to reach stand
			 requirements.
(b)
Inner
			 zones.
Forest practices in the inner zone must be conducted in such a
			 way as to meet or exceed stand requirements to achieve the goal in WAC
			 222-30-010(2).
			 The width of the inner zone is determined by site class, bankfull width, and
			 management option. Timber harvest in this zone must be consistent with the
			 stand requirements in order to reach the desired future condition targets.
"Stand requirement"
means a number of trees per
				acre, the basal area and the proportion of conifer in the combined inner zone
				and adjacent core zone so that the growth of the trees would meet desired
				future conditions. The following table defines basal area targets when the
				stand is one hundred forty years old.
Site Class
Desired future condition target basal area per acre
						(at 140 years)
I
325 sq. ft.
II
325 sq. ft.
III
325 sq. ft.
IV
325 sq. ft.
V
325 sq. ft.
Growth modeling is necessary to calculate whether a particular
				stand meets stand requirement and is on a trajectory towards these desired
				future condition basal area target. The appropriate growth model will be based
				on stand characteristics and will include at a minimum, the following
				components: The number of trees by diameter class, the percent of conifer and
				hardwood, and the age of the stand. See board manual section 7.
(i)
Hardwood conversion in the inner
			 zone.
When the existing stands in the combined core and inner zone do
			 not meet stand requirements, no harvest is permitted in the inner zone, except
			 in connection with hardwood conversion.
The landowner may elect to convert hardwood-dominated stands
				in the
inner zone
to conifer-dominated stands. Harvesting and
				replanting shall be in accordance with the following limits:
(A) Conversion activities in the
inner
			 zone
of any harvest unit are only allowed where all of the following are
			 present:
. Existing stands in the combined core and inner zone do not
				meet stand requirements (WAC
				222-30-021(1)(b));
. There are fewer than fifty-seven conifer trees per acre eight
				inches or larger dbh in the conversion area;
. There are fewer than one hundred conifer trees per acre
				larger than four inches dbh in the conversion area;
. There is evidence (such as conifer stumps, historical photos,
				or a conifer understory) that the conversion area can be successfully
				reforested with conifer and support the development of conifer stands;
. The landowner owns five hundred feet upstream and five
				hundred feet downstream of the harvest unit;
. The core and inner zones contain no stream adjacent parallel
				roads;
. Riparian areas contiguous to the proposed harvest unit are
				owned by the landowner proposing to conduct the conversion activities, and meet
				shade requirements of WAC
				222-30-040 or have a seventy-five
				foot buffer with trees at least forty feet tall on both sides of the stream for
				five hundred feet upstream and five hundred feet downstream of the proposed
				harvest unit (or the length of the stream, if less);
. If the landowner has previously converted hardwood-dominated
				stands, then post-harvest treatments must have been performed to the
				satisfaction of the department.
(B) In addition to the conditions set forth
			 above, permitted conversion activities in the
inner zone
of any
			 harvest unit are limited by the following:
. Each continuous conversion area is not more than five hundred
				feet in length; two conversion areas will be considered "continuous" unless the
				no-harvest area separating the two conversion areas is at least half the length
				of the larger of the two conversion areas.
. Type S and F (Type 1, 2, or 3) Water: Up to fifty percent of
				the inner zone area of the harvest unit on one side of the stream may be
				converted provided that:
. The landowner owns the opposite side of the stream and the
				landowner's riparian area on the opposite bank meets the shade requirements of
				WAC 222-30-040 or has a seventy-five
				foot buffer of trees at least forty feet tall or:
. The landowner does not own land on the opposite side of the
				stream but the riparian area on the opposite bank meets the shade requirements
				of WAC 222-30-040 or has a seventy-five
				foot buffer of trees at least forty feet tall.
. Not more than twenty-five percent of the inner zone of the
				harvest unit on both sides of a Type S or F Water may be converted if the
				landowner owns both sides.
(C) Where conversion is allowed in the
inner zone,
trees within the conversion area may be harvested
			 except that:
. Conifer trees larger than twenty inches dbh shall not be
				harvested;
. Not more than ten percent of the conifer stems greater than
				eight inches dbh, exclusive of the conifer noted above, within the conversion
				area may be harvested; and
. The landowner must exercise reasonable care in the conduct of
				harvest activities to minimize damage to all residual conifer trees within the
				conversion area including conifer trees less than eight inches dbh.
(D) Following harvest in conversion areas,
			 the landowner must:
. Reforest the conversion area with
conifer
tree
				species suitable to the site in accordance with the requirements of WAC
				222-34-010; and
. Conduct post-harvest treatment of the site until the conifer
				trees necessary to meet acceptable stocking levels in WAC
				222-34-010(2) have crowns above the brush or until the conversion area contains a minimum of
				one hundred fifty conifer trees greater than eight inches dbh per acre.
. Notify the department in writing within three years of the
				approval of the forest practices application for hardwood conversion, if the
				hardwood conversion has been completed.
(E)
Tracking hardwood
			 conversion.
The purpose of tracking hardwood conversion is to determine
			 if hardwood conversion is resulting in adequate enhancement of riparian
			 functions toward the desired future condition while minimizing the short term
			 impacts on functions. The department will use existing or updated data bases
			 developed in cooperation with the Washington Hardwoods Commission to identify
			 watershed administrative units (WAUs) with a high percentage of
			 hardwood-dominated riparian areas and, thus have the potential for excessive
			 hardwood conversion under these rules. The department will track the rate of
			 conversion of hardwoods in the riparian zone: (1) Through the application
			 process on an annual basis; and (2) at a WAU scale on a biennial basis as per
			 WAC 222-30-120 through the adaptive
			 management process which will develop thresholds of impact for hardwood
			 conversion at the watershed scale.
(ii)
Harvest options.
(A) No inner zone management. When the
			 existing stands in the combined core and inner zone do not meet stand
			 requirements, no harvest is permitted in the inner zone. When no harvest is
			 permitted in the inner zone or the landowner chooses not to enter the inner
			 zone, the width of core, inner and outer zones are as provided in the following
			 table:
No inner zone management RMZ widths for Western
				Washington
Site Class
RMZ width
Core zone width
Inner zone width
(measured from
						outer edge of core zone)
Outer zone width
(measured from
						outer edge of inner zone)
(measured from outer edge of bankfull width or outer edge
						of CMZ of water)
stream width [LESS THAN EQUALS TO]10'
stream width >10'
stream width [LESS THAN EQUALS TO]10'
stream width >10'
I
200'
50'
83'
100'
67'
50'
II
170'
50'
63'
78'
57'
42'
III
140'
50'
43'
55'
47'
35'
IV
110'
50'
23'
33'
37'
27'
V
90'
50'
10'
18'
30'
22'
(B)
			 Inner zone management. If trees can be harvested and removed from the inner
			 zone because of surplus basal area consistent with the stand requirement, the
			 harvest and removal of the trees must be undertaken consistent with one of two
			 options:
(I)
Option 1. Thinning from
			 below.
The objective of thinning is to distribute stand requirement
			 trees in such a way as to shorten the time required to meet large wood, fish
			 habitat and water quality needs. This is achieved by increasing the potential
			 for leave trees to grow larger than they otherwise would without thinning.
			 Thinning harvest under option 1 must comply with the following:
. Residual trees left in the combined core and inner zones must
				meet stand requirements necessary to be on a trajectory to desired future
				condition. See board manual section 7 for guidelines.
. Thinning must be from below, meaning the smallest dbh trees
				are selected for harvest first, then progressing to successively larger
				diameters.
. Thinning cannot decrease the proportion of conifer in the
				stand.
. Shade retention to meet the shade rule must be confirmed by
				the landowner for any harvest inside of seventy-five feet from the outer edge
				of bankfull width or outer edge of CMZ, whichever is greater.
. The number of residual conifer trees per acre in the inner
				zone will equal or exceed fifty-seven.
Option 1. Thinning from below.
Site class
RMZ width
Core zone width
Inner zone width
(measured from
						outer edge of core zone)
Outer zone width
(measured from
						outer edge of inner zone)
(measured from outer edge of bankfull width or outer edge
						of CMZ of water)
stream width [LESS THAN EQUALS TO]10'
stream width >10'
stream width [LESS THAN EQUALS TO]10'
stream width >10'
I
200'
50'
83'
100'
67'
50'
II
170'
50'
63'
78'
57'
42'
III
140'
50'
43'
55'
47'
35'
IV
110'
50'
23'
33'
37'
27'
V
90'
50'
10'
18'
30'
22'
(II)
Option 2. Leaving trees closest to the water.
Management option 2
			 applies only to riparian management zones for site class I, II, and III on
			 streams that are less than or equal to ten feet wide and RMZs in site class I
			 and II for streams greater than ten feet wide. Harvest must comply with the
			 following:
. Harvest is not permitted within thirty feet of the core zone
				for streams less than or equal to ten feet wide and harvest is not permitted
				within fifty feet of the core zone for streams greater than ten feet
				wide;
. Residual leave trees in the combined core and inner zone must
				meet stand requirements necessary to be on a trajectory to desired future
				condition. See board manual section 7 for calculating stand requirements; outer
				zone can be reduced only to a minimum of ten trees per
. A minimum of twenty conifers per acre, with a minimum twelve
				inch dbh, will be retained in any portion of the inner zone where even-age
				harvest occurs. These riparian leave trees will be counted towards meeting
				applicable stand requirements. The number of riparian leave trees cannot be
				reduced below twenty for any reason.
. Trees are selected for harvest starting from the outer most
				portion of the inner zone first then progressively closer to the stream.
. If (b)(ii)(B)(II) of this subsection results in surplus basal
				area per the stand requirement, the landowner may take credit for the surplus
				by harvesting additional riparian leave trees required to be left in the
				adjacent outer zone on a basal area-for-basal area basis. The number of leave
				trees in the acre.
Option 2. Leaving trees closest to water.
Site class
RMZ width
Core zone width
(measured from
						outer edge of bank-full width or outer edge of CMZ of water)
Inner zone width
Outer zone width
(measured from
						outer edge of inner zone)
stream width [LESS THAN EQUALS TO]10'
stream width [LESS THAN EQUALS TO]10'
stream width [GREATER THAN]10'
stream width [GREATER THAN]10'
stream width <10'
stream width <10'
minimum floor distance
minimum floor distance
(measured from outer edge of core zone)
(measured from outer edge of core zone)
(measured from outer edge of core zone)
(measured from outer edge of core zone)
I
200'
50'
84'
30'
84'
50'
66'
66'
II
170'
50'
64'
30'
70'
50'
56'
50'
III
140'
50'
44'
30'
**
**
46'
**
** Option 2 for site class III on streams >10' is not
				permitted because of the minimum floor (100') constraint.
(iii)
Where the basal area components of the stand requirement cannot be
			 met
within the sum of the areas in the inner and core zone due to the
			 presence of a stream-adjacent parallel road in the inner or core zone, a
			 determination must be made of the approximate basal area that would have been
			 present in the inner and core zones if the road was not occupying space in the
			 core or inner zone and the shortfall in the basal area component of the stand
			 requirement. See definition of "stream-adjacent parallel road" in WAC
			 222-16-010.
(A) Trees containing basal area equal to the
			 amount determined in (b)(iii) of this subsection will be left elsewhere in the
			 inner or outer zone, or if the zones contain insufficient riparian leave trees,
			 substitute riparian leave trees will be left within the RMZ width of other Type
			 S or F Waters in the same unit or along Type Np or Ns Waters in the same unit
			 in addition to all other RMZ requirements on those same Type S, F, Np or Ns
			 Waters.
(B) When the
			 stream-adjacent road basal area calculated in (b)(iii) of this subsection
			 results in an excess in basal area (above stand requirement) then the landowner
			 may receive credit for such excess which can be applied on a basal
			 area-by-basal area basis against the landowner's obligation to leave trees in
			 the outer zone of the RMZ of such stream or other waters within the same unit,
			 provided that the number of trees per acre in the outer zone is not reduced to
			 less than ten trees per acre.
(C)
			 When the basal area requirement cannot be met, as explained in (b)(iii) of this
			 subsection, the shortfall may be reduced through the implementation of an
			 acceptable large woody debris placement plan. See board manual section 26 for
			 guidelines.
(iv) If a
			 harvest operation includes both yarding and harvest activities within the RMZ,
			 all calculations of basal area for stand requirements will be determined as if
			 the yarding corridors were constructed prior to any other harvest activities.
			 If trees cut or damaged by yarding are taken from excess basal area, these
			 trees may be removed from the inner zone. Trees cut or damaged by yarding in a
			 unit which does not meet the basal area target of the stand requirements cannot
			 be removed from the inner zone. Any trees cut or damaged by yarding in the core
			 zone may not be removed.
(c)
Outer zones.
Timber harvest
			 in the outer zone must leave twenty riparian leave trees per acre after
			 harvest.
"Outer zone riparian leave trees"
are trees that must be
			 left after harvest in the outer zone in Western Washington. Riparian leave
			 trees must be left uncut throughout all future harvests:
Outer zone riparian leave tree requirements
Application
Leave tree spacing
Tree species
Minimum dbh required
Outer zone
Dispersed
Conifer
12" dbh or greater
Outer zone
Clumped
Conifer
12" dbh or greater
Protection of sensitive features
Clumped
Trees representative of the overstory including both
						hardwood and conifer
8" dbh or greater
The twenty riparian leave trees to be left can be reduced in
				number under the circumstances delineated in (c)(iv) of this subsection. The
				riparian leave trees must be left on the landscape according to one of the
				following two strategies. A third strategy is available to landowners who agree
				to a LWD placement plan.
(i)
Dispersal strategy.
Riparian leave trees, which means conifer
			 species with a diameter measured at breast height (dbh) of twelve inches or
			 greater, must be left dispersed approximately evenly throughout the outer zone.
			 If riparian leave trees of twelve inches dbh or greater are not available, then
			 the next largest conifers must be left. If conifers are not present, riparian
			 leave trees must be left according to the clumping strategy in (c)(ii) of this
			 subsection.
(ii)
Clumping
			 strategy.
Riparian leave trees must be left clumped in the following
			 way:
(A) Clump trees in or around one or more
			 of the following
sensitive features
to the extent available within
			 the outer zone. When clumping around sensitive features, riparian leave trees
			 must be eight inches dbh or greater and representative of the overstory canopy
			 trees in or around the sensitive feature and may include both hardwood and
			 conifer species. Sensitive features are:
(I)
			 Seeps and springs;
(II) Forested
			 wetlands;
(III) Topographic
			 locations (and orientation) from which leave trees currently on the site will
			 be delivered to the water;
(IV)
			 Areas where riparian leave trees may provide wind-throw protection;
(V) Small unstable, or potentially unstable,
			 slopes not of sufficient area to be detected by other site evaluations. See WAC
			 222-16-050(1)(d).
(VI) Archaeological sites or historic
			 archaeological resources as defined in
			 RCW
			    27.53.030;
(VII) Historic sites eligible for listing on
			 the National Register of Historic Places or the Washington Heritage Register as
			 determined by the Washington state department of archaeology and historic
			 preservation. See WAC
			 222-16-050(1)(f);
			 or
(VIII) Sites containing evidence
			 of Native American cairns, graves or glyptic records as provided for in
			 chapters 27.44 and
			 27.53 RCW. See WAC
			 222-16-050(1)(f).
(B) If sensitive features are not
			 present, then clumps must be well distributed throughout the outer zone and the
			 leave trees must be of conifer species with a dbh of twelve inches or greater.
			 When placing clumps, the applicant will consider operational and biological
			 concerns. Tree counts must be satisfied regardless of the presence of
			 stream-adjacent parallel roads in the outer zone.
(iii)
Large woody debris in-channel
			 placement strategy.
(A) In order to
			 reduce the number of required outer zone trees, a landowner may design a LWD
			 placement plan for department approval consistent with guidelines in board
			 manual sections 5 and 26. Landowners are encouraged to consult with the
			 department and the department of fish and wildlife while designing the plan and
			 prior to submitting a forest practices application.
(B) Reduction of trees in the outer zone must
			 not go below a minimum of ten trees per acre.
(C) If this strategy is chosen, a complete
			 forest practices application must include the LWD placement plan.
(iv)
Twenty riparian leave
			 trees must be left after harvest
with the exception of the following:
(A) If a landowner agrees to implement a
			 placement strategy, see (iii) of this subsection.
(B) If trees are left in an associated
			 channel migration zone, the landowner may reduce the number of trees required
			 to be left according to the following:
(I)
			 Offsets will be measured on a basal area-for-basal area basis.
(II) Conifer in a CMZ equal to or greater
			 than six inches dbh will offset conifer in the outer zone at a one-to-one
			 ratio.
(III) Hardwood in a CMZ
			 equal to or greater than ten inches dbh will offset hardwood in the outer zone
			 at a one-to-one ratio.
(IV)
			 Hardwood in a CMZ equal to or greater than ten inches dbh will offset conifer
			 in the outer zone at a three-to-one ratio.