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HomeMy WebLinkAboutRS_S_Singh_Offsite_Critical_Areas_190405HABITAT TECHNOLOGIES wetlands, streams, fisheries, wildlife – mitigation and permitting solutions P.O. Box 1088, Puyallup, Washington 98371 253-845-5119 contact@habitattechnologies.net March 15, 2019 Mr. Phil Kitzes @PK Enterprises 23025 SE 263rd Street Maple Valley, Washington 98038 e-mail pkenterprises.mv@gmail.com RE: S.Singh Short Plat – LUA17-000803 – Parcel 0007200196 Offsite Wetland and Drainages, City of Renton Dear Mr. Kitzes, Consistent with our discussions Habitat Technologies has re-visited the project site between the end of 2018 through the middle of March 2019 to complete a characterization of the small wetland area and surface water drainage corridors identified offsite to the west (downslope) of the proposed S.Singh Short Plat. Particular emphasis was placed on an appropriate categorization of the small offsite wetland and three identified surface water drainages consistent with the provisions of the Washington State Wetland Rating System for Western Washington: 2014 Update Publication #14-06-029 (Hruby 2014), and the City of Renton Chapter 4.3.050 – Critical Areas Regulations. The small offsite wetland and surface water drainages had previously been defined within a wetland assessment completed by Talasaea Consultants, Inc. during 2006. Offsite Wetland: As identified within the recent assessments, this small offsite wetland exhibited all three of the established criteria for designation as a “wetland.” The wetland exhibited slope characteristics with hydrologic support provided by hillside drainage (noted below as Drainage B) and seeps at the edge of the wetland. The soil throughout this wetland appeared dominated by captured alluvial sediments that were well intermixed with grass and sedge roots. As identified onsite the downslope edge of t his wetland area was formed by an o ld concrete foundation/wall installed either for prior buildings or specifically to create a small ornamental pond. Plant species dominant within is wetland included reed canarygrass (Phalaris arundinacea), small fruited bulrush (Scirpus microcarpus), and common lady fern (Athyrium filix-femina). The outer boundary of this wetland included red alder (Alnus rubra), salmonberry (Rubus spectabilis), Himalayan blackberry (Rubus procera), rose (Rosa spp.), and Douglas spiraea (Spiraea douglasii) (see Photos). As defined using the W etland Rating System (Hruby 2014) this offsite wetland was identified to achieve a total functions score of 16 points (with 4 habitat points) (Appendix A). As defined by the City of Renton a wetland with a total functions score of 16 points would meet the criteria for designation as a Category III Wetland. The standard buffer 2 16232 for a Category III W etland with a habitats score of 4 points would be 50 feet in width as measured perpendicular from the defined wetland edge. Surface Water Drainages: As defined by prior assessments three (3) surface water drainages are present within or immediately adjacent to the project site. All three of these drainages convey stormwater runoff from upslope developed residential areas generally east to southwesterly. Two (2) of these intentionally created systems (noted as Drainage A and Drainage B) enter the eastern boundary of t he project site via installed culverts. The third of these intentionally created systems (notes as Drainage C) is located immediately offsite to the west of the northwest corner of the project site and is associated with the Cedar Avenue stormwater syste m. Drainage A passes through the project site within a well-defined ravine and then continues generally to the west within what appears to be a created ditch through the adjacent powerline corridor. Drainage A appears best defined as an intentionally created system until its confluence with Thunder Hills Creek to the southwest of the project site. Drainage B passes through the project site within a well-defined ravine and then continues generally to the west to enter an offsite wetland (noted above). East of this offsite wetland Drainage B appears best defined as an intentionally created system. However, within the offsite wetland Drainage B combines with a number of hillside seeps such that the drainage for this offsite wetland – while modified by prior developments – would take on the character of a natural drainage corridor. As such, Drainage B as it leave the offsite wetland would appear best defined as a City of Renton Type Ns Water (stream). Drainage B eventually enters Thunder Hills Creek to the southwest of the project site. Drainage C originates from a culvert at the end of Cedar Avenue and generally passes southwesterly adjacent an old internal maintenance roadway within a well-defined ravine. Drainage C enters Drainage B downslope (west) of the offsite wetland. Upslope of its confluence with Drainage B, Drainage C appears best defined as an intentionally created system. CONCLUSION As defined by onsite assessment and prior mapping neither the offsite wetland nor the standard City of Renton buffers associated with the offsite wetland or offsite Type Ns Water would encroach into the western edge of the proposed S.Singh Short Plat (Figure 1). Sincerely, Thomas D. Deming, PWS Habitat Technologies 3 16232 FIGURE ★ MN 15°30' Figure 1 Offsite Wetland Graphic 50 ft 4 16232 PHOTOS 5 16232 View easterly across offsite wetland. View of concrete foundation at western edge of wetland. 6 16232 View across offsite wetland area. View across the offsite wetland. 7 16232 APPENDIX A ★ MN 15°30' Figure A2 25 ft ★ MN 15°30' Figure A2 500 ft Figure A4 WA Dept. of Ecology© 2019 Microsoft Corporation © 2019 DigitalGlobe ©CNES (2019)Distribution Airbus DS © 2019 HERE March 13, 2019 0 0.5 10.25Miles K AssessedWaters/Sediment Water Category 5 - 303d Category 4C Category 4B Category 4A Category 2 Category 1 Sedim ent Category 5 - 303d Category 4C Category 4B Category 4A Category 2 Category 1 WQ Standards Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 1 Rating Form – Effective January 1, 2015 Score for each function based on three ratings (order of ratings is not important) 9 = H,H,H 8 = H,H,M 7 = H,H,L 7 = H,M,M 6 = H,M,L 6 = M,M,M 5 = H,L,L 5 = M,M,L 4 = M,L,L 3 = L,L,L RATING SUMMARY – Western Washington Name of wetland (or ID #): _________________________________ Date of site visit: _____ Rated by____________________________ Trained by Ecology?__ Yes ___No Date of training______ HGM Class used for rating_________________ Wetland has multiple HGM classes?___Y ____N NOTE: Form is not complete without the figures requested (figures can be combined). Source of base aerial photo/map ______________________________________ OVERALL WETLAND CATEGORY ____ (based on functions___ or special characteristics___) 1. Category of wetland based on FUNCTIONS _______Category I – Total score = 23 - 27 _______Category II – Total score = 20 - 22 _______Category III – Total score = 16 - 19 _______Category IV – Total score = 9 - 15 FUNCTION Improving Water Quality Hydrologic Habitat Circle the appropriate ratings Site Potential H M L H M L H M L Landscape Potential H M L H M L H M L Value H M L H M L H M L TOTAL Score Based on Ratings 2. Category based on SPECIAL CHARACTERISTICS of wetland CHARACTERISTIC CATEGORY Estuarine I II Wetland of High Conservation Value I Bog I Mature Forest I Old Growth Forest I Coastal Lagoon I II Interdunal I II III IV None of the above Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 2 Rating Form – Effective January 1, 2015 Maps and figures required to answer questions correctly for Western Washington Depressional Wetlands Map of: To answer questions: Figure # Cowardin plant classes D 1.3, H 1.1, H 1.4 Hydroperiods D 1.4, H 1.2 Location of outlet (can be added to map of hydroperiods) D 1.1, D 4.1 Boundary of area within 150 ft of the wetland (can be added to another figure) D 2.2, D 5.2 Map of the contributing basin D 4.3, D 5.3 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat H 2.1, H 2.2, H 2.3 Screen capture of map of 303(d) listed waters in basin (from Ecology website) D 3.1, D 3.2 Screen capture of list of TMDLs for WRIA in which unit is found (from web) D 3.3 Riverine Wetlands Map of: To answer questions: Figure # Cowardin plant classes H 1.1, H 1.4 Hydroperiods H 1.2 Ponded depressions R 1.1 Boundary of area within 150 ft of the wetland (can be added to another figure) R 2.4 Plant cover of trees, shrubs, and herbaceous plants R 1.2, R 4.2 Width of unit vs. width of stream (can be added to another figure) R 4.1 Map of the contributing basin R 2.2, R 2.3, R 5.2 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat H 2.1, H 2.2, H 2.3 Screen capture of map of 303(d) listed waters in basin (from Ecology website) R 3.1 Screen capture of list of TMDLs for WRIA in which unit is found (from web) R 3.2, R 3.3 Lake Fringe Wetlands Map of: To answer questions: Figure # Cowardin plant classes L 1.1, L 4.1, H 1.1, H 1.4 Plant cover of trees, shrubs, and herbaceous plants L 1.2 Boundary of area within 150 ft of the wetland (can be added to another figure) L 2.2 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat H 2.1, H 2.2, H 2.3 Screen capture of map of 303(d) listed waters in basin (from Ecology website) L 3.1, L 3.2 Screen capture of list of TMDLs for WRIA in which unit is found (from web) L 3.3 Slope Wetlands Map of: To answer questions: Figure # Cowardin plant classes H 1.1, H 1.4 Hydroperiods H 1.2 Plant cover of dense trees, shrubs, and herbaceous plants S 1.3 Plant cover of dense, rigid trees, shrubs, and herbaceous plants (can be added to figure above) S 4.1 Boundary of 150 ft buffer (can be added to another figure) S 2.1, S 5.1 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat H 2.1, H 2.2, H 2.3 Screen capture of map of 303(d) listed waters in basin (from Ecology website) S 3.1, S 3.2 Screen capture of list of TMDLs for WRIA in which unit is found (from web) S 3.3 Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 3 Rating Form – Effective January 1, 2015 HGM Classification of Wetlands in Western Washington 1. Are the water levels in the entire unit usually controlled by tides except during floods? NO – go to 2 YES – the wetland class is Tidal Fringe – go to 1.1 1.1 Is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)? NO – Saltwater Tidal Fringe (Estuarine) YES – Freshwater Tidal Fringe If your wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands. If it is Saltwater Tidal Fringe it is an Estuarine wetland and is not scored. This method cannot be used to score functions for estuarine wetlands. 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Groundwater and surface water runoff are NOT sources of water to the unit. NO – go to 3 YES – The wetland class is Flats If your wetland can be classified as a Flats wetland, use the form for Depressional wetlands. 3. Does the entire wetland unit meet all of the following criteria? ___The vegetated part of the wetland is on the shores of a body of permanent open water (without any plants on the surface at any time of the year) at least 20 ac (8 ha) in size; ___At least 30% of the open water area is deeper than 6.6 ft (2 m). NO – go to 4 YES – The wetland class is Lake Fringe (Lacustrine Fringe) 4. Does the entire wetland unit meet all of the following criteria? ____The wetland is on a slope (slope can be very gradual), ____The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without distinct banks, ____The water leaves the wetland without being impounded. NO – go to 5 YES – The wetland class is Slope NOTE: Surface water does not pond in these type of wetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3 ft diameter and less than 1 ft deep). 5. Does the entire wetland unit meet all of the following criteria? ____The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river, ____The overbank flooding occurs at least once every 2 years. For questions 1-7, the criteria described must apply to the entire unit being rated. If the hydrologic criteria listed in each question do not apply to the entire unit being rated, you probably have a unit with multiple HGM classes. In this case, identify which hydrologic criteria in questions 1-7 apply, and go to Question 8. Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 4 Rating Form – Effective January 1, 2015 NO – go to 6 YES – The wetland class is Riverine NOTE: The Riverine unit can contain depressions that are filled with water when the river is not flooding 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at some time during the year? This means that any outlet, if present, is higher than the interior of the wetland. NO – go to 7 YES – The wetland class is Depressional 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding? The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet. NO – go to 8 YES – The wetland class is Depressional 8. Your wetland unit seems to be difficult to classify and probably contains several different HGM classes. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a Depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present within the wetland unit being scored. NOTE: Use this table only if the class that is recommended in the second column represents 10% or more of the total area of the wetland unit being rated. If the area of the HGM class listed in column 2 is less than 10% of the unit; classify the wetland using the class that represents more than 90% of the total area. HGM classes within the wetland unit being rated HGM class to use in rating Slope + Riverine Riverine Slope + Depressional Depressional Slope + Lake Fringe Lake Fringe Depressional + Riverine along stream within boundary of depression Depressional Depressional + Lake Fringe Depressional Riverine + Lake Fringe Riverine Salt Water Tidal Fringe and any other class of freshwater wetland Treat as ESTUARINE If you are still unable to determine which of the above criteria apply to your wetland, or if you have more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the rating. Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 11 Rating Form – Effective January 1, 2015 SLOPE WETLANDS Water Quality Functions - Indicators that the site functions to improve water quality S 1.0. Does the site have the potential to improve water quality? S 1.1. Characteristics of the average slope of the wetland: (a 1% slope has a 1 ft vertical drop in elevation for every 100 ft of horizontal distance) Slope is 1% or less points = 3 Slope is > 1%-2% points = 2 Slope is > 2%-5% points = 1 Slope is greater than 5% points = 0 S 1.2. The soil 2 in below the surface (or duff layer) is true clay or true organic (use NRCS definitions): Yes = 3 No = 0 S 1.3. Characteristics of the plants in the wetland that trap sediments and pollutants: Choose the points appropriate for the description that best fits the plants in the wetland. Dense means you have trouble seeing the soil surface (>75% cover), and uncut means not grazed or mowed and plants are higher than 6 in. Dense, uncut, herbaceous plants > 90% of the wetland area points = 6 Dense, uncut, herbaceous plants > ½ of area points = 3 Dense, woody, plants > ½ of area points = 2 Dense, uncut, herbaceous plants > ¼ of area points = 1 Does not meet any of the criteria above for plants points = 0 Total for S 1 Add the points in the boxes above Rating of Site Potential If score is: 12 = H 6-11 = M 0-5 = L Record the rating on the first page S 2.0. Does the landscape have the potential to support the water quality function of the site? S 2.1. Is > 10% of the area within 150 ft on the uphill side of the wetland in land uses that generate pollutants? Yes = 1 No = 0 S 2.2. Are there other sources of pollutants coming into the wetland that are not listed in question S 2.1? Other sources ________________ Yes = 1 No = 0 Total for S 2 Add the points in the boxes above Rating of Landscape Potential If score is: 1-2 = M 0 = L Record the rating on the first page S 3.0. Is the water quality improvement provided by the site valuable to society? S 3.1. Does the wetland discharge directly (i.e., within 1 mi) to a stream, river, lake, or marine water that is on the 303(d) list? Yes = 1 No = 0 S 3.2. Is the wetland in a basin or sub-basin where water quality is an issue? At least one aquatic resource in the basin is on the 303(d) list. Yes = 1 No = 0 S 3.3. Has the site been identified in a watershed or local plan as important for maintaining water quality? Answer YES if there is a TMDL for the basin in which unit is found. Yes = 2 No = 0 Total for S 3 Add the points in the boxes above Rating of Value If score is: 2-4 = H 1 = M 0 = L Record the rating on the first page Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 12 Rating Form – Effective January 1, 2015 SLOPE WETLANDS Hydrologic Functions - Indicators that the site functions to reduce flooding and stream erosion S 4.0. Does the site have the potential to reduce flooding and stream erosion? S 4.1. Characteristics of plants that reduce the velocity of surface flows during storms: Choose the points appropriate for the description that best fits conditions in the wetland. Stems of plants should be thick enough (usually > 1/8 in), or dense enough, to remain erect during surface flows . Dense, uncut, rigid plants cover > 90% of the area of the wetland points = 1 All other conditions points = 0 Rating of Site Potential If score is: 1 = M 0 = L Record the rating on the first page S 5.0. Does the landscape have the potential to support the hydrologic functions of the site? S 5.1. Is more than 25% of the area within 150 ft upslope of wetland in land uses or cover that generate excess surface runoff? Yes = 1 No = 0 Rating of Landscape Potential If score is: 1 = M 0 = L Record the rating on the first page S 6.0. Are the hydrologic functions provided by the site valuable to society? S 6.1. Distance to the nearest areas downstr eam that have flooding problems: The sub-basin immediately down-gradient of site has flooding problems that result in damage to human or natural resources (e.g., houses or salmon redds) points = 2 Surface flooding problems are in a sub-basin farther down-gradient points = 1 No flooding problems anywhere downstream points = 0 S 6.2. Has the site been identified as important for flood storage or flood conveyance in a regional flood control plan? Yes = 2 No = 0 Total for S 6 Add the points in the boxes above Rating of Value If score is: 2-4 = H 1 = M 0 = L Record the rating on the first page NOTES and FIELD OBSERVATIONS: Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 13 Rating Form – Effective January 1, 2015 These questions apply to wetlands of all HGM classes. HABITAT FUNCTIONS - Indicators that site functions to provide important habitat H 1.0. Does the site have the potential to provide habitat? H 1.1. Structure of plant community: Indicators are Cowardin classes and strata within the Forested class. Check the Cowardin plant classes in the wetland. Up to 10 patches may be combined for each class to meet the threshold of ¼ ac or more than 10% of the unit if it is smaller than 2.5 ac. Add the number of structures checked. ____Aquatic bed 4 structures or more: points = 4 ____Emergent 3 structures: points = 2 ____Scrub-shrub (areas where shrubs have > 30% cover) 2 structures: points = 1 ____Forested (areas where trees have > 30% cover) 1 structure: points = 0 If the unit has a Forested class, check if: ____The Forested class has 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover) that each cover 20% within the Forested polygon H 1.2. Hydroperiods Check the types of water regimes (hydroperiods) present within the wetland. The water regime has to cover more than 10% of the wetland or ¼ ac to count (see text for descriptions of hydroperiods). ____Permanently flooded or inundated 4 or more types present: points = 3 ____Seasonally flooded or inundated 3 types present: points = 2 ____Occasionally flooded or inundated 2 types present: points = 1 ____Saturated only 1 type present: points = 0 ____Permanently flowing stream or river in, or adjacent to, the wetland ____Seasonally flowing stream in, or adjacent to, the wetland ____Lake Fringe wetland 2 points ____Freshwater tidal wetland 2 points H 1.3. Richness of plant species Count the number of plant species in the wetland that cover at least 10 ft 2. Different patches of the same species can be combined to meet the size threshold and you do not have to name the species. Do not include Eurasian milfoil, reed canarygrass, purple loosestrife, Canadian thistle If you counted: > 19 species points = 2 5 - 19 species points = 1 < 5 species points = 0 H 1.4. Interspersion of habitats Decide from the diagrams below whether interspersion among Cowardin plants classes (described in H 1.1), or the classes and unvegetated areas (can include open water or mudflats) is high, moderate, low, or none. If you have four or more plant classes or three classes and open water, the rating is always high. None = 0 points Low = 1 point Moderate = 2 points All three diagrams in this row are HIGH = 3points Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 14 Rating Form – Effective January 1, 2015 H 1.5. Special habitat features: Check the habitat features that are present in the wetland. The number of checks is the number of points. ____Large, downed, woody debris within the wetland (> 4 in diameter and 6 ft long). ____Standing snags (dbh > 4 in) within the wetland ____Undercut banks are present for at least 6.6 ft (2 m) and/or overhanging plants extends at least 3.3 ft (1 m) over a stream (or ditch) in, or contiguous with the wetland, for at least 33 ft (10 m) ____Stable steep banks of fine material that might be used by beaver or muskrat for denning (> 30 degree slope) OR signs of recent beaver activity are present (cut shrubs or trees that have not yet weathered where wood is exposed) ____At least ¼ ac of thin-stemmed persistent plants or woody branches are present in areas that are permanently or seasonally inundated (structures for egg-laying by amphibians) ____Invasive plants cover less than 25% of the wetland area in every stratum of plants (see H 1.1 for list of strata) Total for H 1 Add the points in the boxes above Rating of Site Potential If score is: 15-18 = H 7-14 = M 0-6 = L Record the rating on the first page H 2.0. Does the landscape have the potential to support the habitat functions of the site? H 2.1. Accessible habitat (include only habitat that directly abuts wetland unit). Calculate: % undisturbed habitat + [(% moderate and low intensity land uses)/2] = _______% If total accessible habitat is: > 1/3 (33.3%) of 1 km Polygon points = 3 20-33% of 1 km Polygon points = 2 10-19% of 1 km Polygon points = 1 < 10% of 1 km Polygon points = 0 H 2.2. Undisturbed habitat in 1 km Polygon around the wetland. Calculate: % undisturbed habitat + [(% moderate and low intensity land uses)/2] = _______% Undisturbed habitat > 50% of Polygon points = 3 Undisturbed habitat 10-50% and in 1-3 patches points = 2 Undisturbed habitat 10-50% and > 3 patches points = 1 Undisturbed habitat < 10% of 1 km Polygon points = 0 H 2.3. Land use intensity in 1 km Polygon: If > 50% of 1 km Polygon is high intensity land use points = (- 2) ≤ 50% of 1 km Polygon is high intensity points = 0 Total for H 2 Add the points in the boxes above Rating of Landscape Potential If score is: 4-6 = H 1-3 = M < 1 = L Record the rating on the first page H 3.0. Is the habitat provided by the site valuable to society? H 3.1. Does the site provide habitat for species valued in laws, regulations, or policies? Choose only the highest score that applies to the wetland being rated. Site meets ANY of the following criteria: points = 2  It has 3 or more priority habitats within 100 m (see next page)  It provides habitat for Threatened or Endangered species (any plant or animal on the state or federal lists)  It is mapped as a location for an individual WDFW priority species  It is a Wetland of High Conservation Value as determined by the Department of Natural Resources  It has been categorized as an important habitat site in a local or regional comprehensive plan, in a Shoreline Master Plan, or in a watershed plan Site has 1 or 2 priority habitats (listed on next page) within 100 m points = 1 Site does not meet any of the criteria above points = 0 Rating of Value If score is: 2 = H 1 = M 0 = L Record the rating on the first page Wetland name or number ______ Wetland Rating System for Western WA: 2014 Update 15 Rating Form – Effective January 1, 2015 WDFW Priority Habitats Priority habitats listed by WDFW (see complete descriptions of WDFW priority habitats, and the counties in which they can be found, in: Washington Department of Fish and Wildlife. 2008. Priority Habitat and Species List. Olympia, Washington. 177 pp. http://wdfw.wa.gov/publications/00165/wdfw00165.pdf or access the list from here: http://wdfw.wa.gov/conservation/phs/list/) Count how many of the following priority habitats are within 330 ft (100 m) of the wetland unit: NOTE: This question is independent of the land use between the wetland unit and the priority habitat.  Aspen Stands: Pure or mixed stands of aspen greater than 1 ac (0.4 ha).  Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions in WDFW PHS report).  Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock.  Old-growth/Mature forests: Old-growth west of Cascade crest – Stands of at least 2 tree species, forming a multi- layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha ) > 32 in (81 cm) dbh or > 200 years of age. Mature forests – Stands with average diameters exceeding 21 in (53 cm) dbh; crown cover may be less than 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth; 80-200 years old west of the Cascade crest.  Oregon White Oak: Woodland stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PHS report p. 158 – see web link above).  Riparian: The area adjacent to aquatic systems with flowing water that contains elements of both aquatic and terrestrial ecosystems which mutually influence each other.  Westside Prairies: Herbaceous, non-forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PHS report p. 161 – see web link above).  Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources.  Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition of relatively undisturbed are in WDFW report – see web link on previous page).  Caves: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human.  Cliffs: Greater than 25 ft (7.6 m) high and occurring below 5000 ft elevation.  Talus: Homogenous areas of rock rubble ranging in average size 0.5 - 6.5 ft (0.15 - 2.0 m), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs.  Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 20 in (51 cm) in western Washington and are > 6.5 ft (2 m) in height. Priority logs are > 12 in (30 cm) in diameter at the largest end, and > 20 ft (6 m) long. Note: All vegetated wetlands are by definition a priority habitat but are not included in this list because they are addressed elsewhere.