Bridge Replacement and HOV Project (Union Bay Natural Area) Mitigation Project

SR 520, I-5 to Medina: Bridge Replacement and HOV Project (Union Bay Natural Area) Mitigation Project

USACE NWS-2008-1246

Northwest Region

2018 (Year One) Monitoring Report

Wetlands Program

Issued December 2018

Environmental Services Office

Author:

Jon Backus, Graduate Student Master of Environmental Horticulture School of Environmental and Forest Sciences, University of Washington [email protected]

Editor:

Kristen Andrews

Contributor:

Dr. Jonathan D. Bakker, Professor School of Environmental and Forest Sciences, University of Washington Box 354115, Seattle, WA 98195-4115 P: 206-221-3864; E: [email protected]

For additional information about this report or the WSDOT Wetlands Program, please contact:

Kristen Andrews, Wetlands Program WSDOT, Environmental Services Office P. O. Box 47332, Olympia, WA 98504 Phone: 360-570-2588 E-mail: [email protected]

Monitoring reports are published on the web at: http://www.wsdot.wa.gov/environment/technical/disciplines/wetlands/monitoring-reports

1 USACE NWS-2008-1246

General Site Information

USACE IP Number NWS-2008-1246

In wetlands and the waters of Union Bay, Mitigation at the City of Seattle, King County, Location Washington.

LLID Number 1222957476583

Construction Date June 2016 – Nov 2018

Monitoring Period 2018

Year of Monitoring 1 of 10

Type of Impact Wetland Buffer

Area of Project 12.76 10.5 acres Impact1 acres

Wetland Wetland Buffer Type of Mitigation Establishme Enhanceme Enhancem nt nt ent

Planned Area of 12.76 1.19 acres 9.31 acre Mitigation¹ acres

1 Impact and mitigation numbers sourced from Washington State Department of Transportation. 2015. SR 520 Bridge Replacement and HOV Program. Final Wetland Mitigation Report

2 Design plan for UBNA mitigation site Source:www.wsdot.wa.gov/sites/default/files/2018/07/11/SR520- factsheet-UnionBayNaturalArea-2018.pdf

Contents

Mitigation Areas 5

Summary of Monitoring Results and Management Activities (2018) 7

Report Introduction 10

What is the Union Bay Natural Area Mitigation Site? 11

What Are the Performance Standards For This Site? 13

How Were the Performance Standards Evaluated? 18

Hydrology Monitoring 18

Vegetation Monitoring 18

Photo-Documentation 22

Habitat Structures 22

How Is the Site Developing? 23

What Is Planned For This Site? 35

Appendix 1 – Additional Figures 37

Appendix 2 – Data Tables 40

Literature Cited 52

Mitigation Areas

The mitigation types designated in the Final Wetland Mitigation Report (WSDOT, 2015) have been assigned alphanumeric type codes for easier reference based on their intended habitat and mitigation type. These codes were also used in the monitoring plan (Chan, 2018) and are used throughout this document. Below is a crosswalk between the original mitigation types and these type codes.

Mitigation Area Wetland Habitat Mitigation Type Seed and Plant Mixes Type Code Area (acres)

Forested Wetland Enhancement Forested Enhancement Tree and shrub F Wet Enh 2.41

Forested Wetland Forested Establishment Tree and shrub F Wet Es 0.28 Establishment

Forested Wetland Enhancement Forested Enhancement Infill Tree and shrub at 30% F Wet Enh 1.67 Infill density Inf

Scrub-Shrub Wetland Scrub-Shrub Enhancement Shrub and emergent Sc-Sh Wet 1.26 Enhancement Enh

Scrub-Shrub Wetland Scrub-Shrub Establishment Shrub and emergent Sc-Sh Wet 0.91 Establishment Est

Emergent Wetland Emergent Enhancement Shrub and emergent Em Wet Enh 2.36 Enhancement

Shoreline Emergent Wetland Shoreline Emergent Enhancement Shrub and emergent Shor Em 1.61 Enhancement Wet Enh

Wetland Buffer Enhancement Buffer Enhancement Tree and shrub Wet Buf Enh 5.82

Wetland Buffer Infill Buffer Infill Tree and shrub at 30% Wet Buf Inf 0.62 density

Reduced Density Wetland Buffer Reduced Density Shrub at 30% density Red Den Buffer Wet Buf

Grass/Herbaceous Wetland Buffer Grass/Herbaceous Grass and forbs Gr/Herb 0.51 Buffer Wet Buf

Summary of Monitoring Results and Management Activities (2018)

Performance Standards 2018 Results Management Activities As-Built Submitted and Approved None Wetland Hydrology (F Wet Est, Sc-Sh Present None Wet Est) Wetland Vegetation Native wetland woody species will Total Woody Density: achieve a density of 4 plants/100 ft² in F Wet Enh /Wet Enh Inf : 4 Additional woody the F Wet Enh & Wet Enh Inf plants/100 ft² species added (combined), F Wet Est, F, Sc-Sh Wet F Wet Est,: 3.6 plants/100 ft² September 2018 Enh, and patches in Em Wet Enh SC-Sh Wet Enh: 2.3 plants/100 ft² Em Wet Enh: 0.9 plants/100 ft² Native wetland woody species will Woody Density: 0.7 plants/100 ft² Additional woody achieve a density of 1.2 plants/100 ft² Herb Cover: 36% cover species added and 25% cover of native wetland September 2018 emergent cover in the Sc-Sh Wet Est Native emergent wetland cover in the Herb Cover: 7% Additional emergent Em Wet Enh will be at least 30% species added September 2018 Native wetland woody species will Woody Density: 0.3 plants/100 ft² Additional emergent achieve a density of 1 plant/100 ft² and Herb Cover: 52% cover and woody species 15% of native emergent wetland cover added September in Shor Em Wet Enh 2018

Structural Complexity

Forested Wetlands inconsistent with vegetation type - currently shrub dominated. F Wet Enh: 33%, F Wet Est: 17%, Wet Enh Inf: 57%

Additional plants Installed vegetation consistent with Scrub-Shrub and Shoreline added September proposed vegetation type inconsistent with vegetation type – 2018 currently herb dominated. Sc-Sh Wet Enh: 25%, Sc-Sh Wet Est: 44%, Shor Em Wet Enh:79% Emergent Wetland consistent with vegetation type – herb dominated.

31% cover

(See Appendix 2, Table 2)

Wetland Buffer Vegetation List of species in the Gr/Herb Wet Buf . Present (See Appendix 2, Table 3 ) Additional herbaceous Verify that species in design are Lupinus lepidus and Achillea species added present. millefolium only species in design September 2018. present, in sparse quantity. Further noxious/invasive weed control needed Native woody species will achieve a Woody Density: 4.5 plants/100 ft² None density of 4 plants/100 ft² in Wet Buf Enh

Native woody species will achieve a Woody Density Wet Buf Inf: 2.6 None density of 1.2 plants/100 ft² in Wet Buf plants/100 ft² Inf, Red Den Wet Buf Woody Density Red Den Wet Buf: 2.3 plants/100 ft² Habitat Habitat Structures Present None Noxious and Invasive Species Control of Class A noxious weeds None present None (entire site) Control of Class B & C noxious weeds Purple loosestrife and garden Eradicate individuals (entire site) loosestrife observed and reported to located, limit further stie managers. spread.

Cover met in most areas. Cover not Additional non-native met in Em Wet Enh and Gr/Herb Wet species control, Select invasive species <10% cover Buf which exceeded 10% combined particularly in Em (entire site) cover Wet Enh and Gr/Herb Wet Buf

No non-native knotweeds observed in Non-native knotweeds (entire site) any mitigation area

Shor Em Wet Enh has 68% cover Continued non-native Reed canarygrass (entire site except All other mitigation areas <10% species control buffer areas) needed, especially in Shor Em Wet Enh

Purple loosestrife detected in all Purple loosestrife (F Wet Enh, Wet Eradicate individuals mitigation areas except Sc-Sh Wet Enh Inf, Sc-Sh Wet Est,Em Wet Enh, located, limit further Est Shor Em Wet Enh mitigation areas) spread.

Garden loosestrife detected in F Wet Eradicate individuals Enh In, Shor Em Wet Enh, Garden loosestrife (entire site) located, limit further Wet Buf Enh, Wet Buf Inf, Red Den, spread. Wet Buf, Gr/Herb Wet Buf

Summary based on data collected and summarized in Appendix 2: Tables 1, 2, 3, 4.

Report Introduction

This report summarizes first-year (Year-1) monitoring activities at the Union Bay Natural Area (UBNA) mitigation site. Included are a site description, the performance standards, an explanation of monitoring methods, and an evaluation of site success. Monitoring was conducted under the guidance of the Year 1 Monitoring Plan (Chan, 2018), following performance standards detailed in the Final Wetland Mitigation Report (WSDOT, 2015). Monitoring activities included assessments of wetland hydrology, vegetation surveys, and photo-documentation. Vegetation monitoring occurred from mid-July until early September 2018, and was conducted by University of Washington graduate student Jon Backus, with assistance from fellow graduate student Victoria Fox.

This report does not include end-of-season mortality counts conducted by WSDOT and UWBG staff and subsequent planting in Fall 2018.

What is the Union Bay Natural Area Mitigation Site?

This 23.26 acre mitigation site (Figure 1) is a combination of 1.19 acres of new wetland establishment, 9.31 acres of wetland enhancement, and 12.76 acres of enhanced wetland and shoreline buffer vegetation.

The wetland establishment consists of 0.28 acres of palustrine forested wetland (F Wet Est ) and 0.91 acres of scrub-shrub wetland (Sc-Sh Wet Est ).

The wetland enhancement includes 1.61 acres of lacustrine wetland (Shor Em Wet Enh L1) and 7.7 acres of palustrine wetland (F Wet Enh, F Wet Enh Inf, Sc-Sh Wet Enh, and Em Wet Enh).

The wetland and shoreline buffer include 6.44 acres planted with woody vegetation (Wet Buf Enh and Wet Buf Inf), 5.82 acres with woody vegetation planted at a reduced density (Red Den Wet Buf), and 0.51 acres sown with herbaceous species (Gr/Herb Wet Buf).

A combination of created wetlands, and enhanced wetlands and buffers were created to compensate for the loss of wetlands due to the SR 520, I-5 to Medina bridge replacement and HOV project. The created wetlands and enhancement areas are designed to provide mitigation for lost wetland functions including wildlife habitat, biological support, and storm water control.

Figure 1: Mitigation Site. The Union Bay Natural Area mitigation project consists of 11 different mitigation areas, including establishment, enhancement and buffer areas. Source: Year 1 Monitoring Plan (Chan, 2018).

What Are the Performance Standards For This Site?

The Year 1 performance standards listed here are excerpted from the Final Wetland Mitigation Report (WSDOT, 2015).

Year 1

1. Hydrologic Performance Standards

1.1. As-built condition documented in as-built report submitted to agencies is consistent with the proposed grading plans or revisions approved by regulatory agencies.

1.2. The wetland establishment areas will be inundated or soils will be saturated to within 12 inches of the soil surface for at least 30 consecutive days during the growing season in years when rainfall meets normal precipitation conditions.

2. Wetland Vegetation Performance Standards

2.1. Forested habitat (F Wet Enh, F Wet Est , F Wet Enh Inf), scrub-shrub habitat (Sc- Sh Wet Enh) and shrub patches in emergent habitat (Em Wet Enh): Planted native wetland woody species will achieve an average density of at least four plants per 100 square feet in planted zones of F Wet Enh and F Wet Enh Inf combined, F Wet Est , Sc-Sh Wet Enh, and shrub patches within Em Wet Enh.

2.2. Scrub-shrub wetland establishment area (Sc-Sh Wet Est): Native wetland woody species will achieve an average density of at least 1.2 plants per 100 square feet in Sc- Sh Wet Est. Cover of native, wetland emergent vegetation will provide at least 25 percent cover in Sc-Sh Wet Est.

2.3. Emergent wetland habitat (Em Wet Enh): Cover of native emergent wetland vegetation will be measured and at least 30 percent will be native emergent cover in Em Wet Enh.

2.4. Emergent shoreline wetland habitat (Shor Em Wet Enh): Cover of native wetland vegetation (herbaceous and planted woody) will be measured. At least 15 percent cover will be native emergent vegetation and planted native woody species will achieve an average density of at least 1 plant per 100 square feet in Shor Em Wet Enh.

3. Structural Complexity Performance Standards

3.2. All wetland habitats, installed vegetation is consistent with the proposed vegetation type as identified in the wetland mitigation planting plans.

4. Wetland Buffer Vegetation Performance Standards

4.1. Grass/Herbaceous wetland buffer (Gr/Herb Wet Buf): Native seed mix or plantings will be accounted for in year one of monitoring with a walk-through identifying species present. A species list will be included in the Year-1 monitoring report to document that the species planted during the establishment are present within the grass/herbaceous wetland buffer. (Noxious Weeds and Invasive Species Performance Standards below will apply to this area as well.)

4.2. Wetland buffer (Wet Buf Enh): Native woody species will achieve an average density of at least four plants per 100 square feet.

4.3. Reduced density wetland buffer (Red Den Wet Buf) and wetland buffer infill (Wet Buf Inf): Native woody species will achieve an average density of at least 1.2 plants per 100 square feet.

5. Habitat Structures Performance Standard

5.1. Installation of habitat structures will be verified and an as-built plan will document that all habitat structures were installed.

6. Noxious Weeds and Invasive Species Performance Standards

6.1. Washington State-listed or King County-listed Class A weeds designated for control by the County weed board must be eradicated. All occurrences shall be immediately reported to the site manager and the King County Noxious Weed Control Program and an eradication program will be initiated within 30 days of the report.

6.2. Designated Class B or C by King County will be controlled annually to prevent seed production and to prevent dispersal of propagative parts that are capable of starting new plants. Known designated Class B and C noxious weeds at the project site are garden loosestrife (Lysimachia vulgaris) and purple loosestrife (Lythrum salicaria).

6.3. The combined cover of non-native blackberries (Rubus armeniacus and R. laciniatus), Scotch broom (Cytisus scoparius), thistles (Cirsium arvense, C. vulgare, Carduus nutans, and Onopordum acanthium), and yellow-flag iris (Iris pseudacorus) will not exceed 10 percent cover, collectively, in the established or enhanced wetland and buffer areas.

6.4. Non-native knotweeds identified on the King County noxious weed list (Polygonum cuspidatum, P. polystachyum, P. bohemicum, P. sachalinense) will be eradicated.

6.5 Reed canarygrass (Phalaris arundinacea) will be managed and controlled to reduce the competition with and to enhance the survival of tree and shrub plantings in all wetland mitigation areas. In wetland enhancement areas along the lake shore, reed canarygrass control will be more difficult. Actions will focus on limiting control while plantings become established. Reed canarygrass will not exceed 25 percent cover in the non-shoreline wetland mitigation areas, and not exceed 50 percent cover in the shoreline wetland mitigation areas.

6.6. No purple loosestrife flowers will be allowed to develop seed at Year 1; flowers will not be present within wetland enhancement areas at time of monitoring in early to mid-August. At Year 1, after initial control, cover will be assessed quantitatively to determine a baseline for purple loosestrife.

6.7. At Year 1, after initial control, cover will be assessed quantitatively to determine a baseline for Garden loosestrife (Lysimachia vulgaris).

How Were the Performance Standards Evaluated? Hydrology Monitoring

Hydrology monitoring (Performance standard 1.2) was completed in the forested wetland establishment (F Wet Est) and scrub-shrub wetland establishment (Sc-Sh Wet Est) areas (Figure 3). Three hydrology monitoring visits occurred between March 22, 2018 and April 19, 2018. The majority of the mitigation areas were inundated at the time of the first visit, so only one sampling location was used at each mitigation area based on accessibility. Documentation

included photos, a description of the extent and location of inundation on-site, and measurements of surface water/observation of hydrology indicators (US Army Corps of Engineers 2010).

The first visit occurred after the growing season began. . The growing season was confirmed by the presence of new growth on two or more different non-evergreen woody species. The second visit was scheduled for about 14 days after the first visit, and the third visit about 14 days later. The same locations will be used in subsequent years.

During each visit to the monitoring locations the depth of standing water in inches (rounded to the nearest 0.5 inch) was measured. If there wasn’t standing water to measure, but the soil was saturated to the surface, then it was recorded as “saturated to the soil surface”. Additionally, a brief description of the extent and location of inundation and surface saturation on-site was recorded as well as photos to illustrate the extent of inundation/surface saturation on-site.

Vegetation Monitoring

Determining Plot Locations

Vegetation monitoring followed the methods set by the Year 1 Monitoring Plan (Chan, 2018). The Generalized Random-Tessellation Stratified (GRTS) spatial sampling method, utilizing the spsurvey package (Kincaid and Olsen, 2011) in R, was used to generate 50 random locations of plot centers within each mitigation area. We generated extra locations to account for the possibility that some points might be determined to be unsuitable for sampling while still allowing us to achieve our goal of 30 plots per mitigation area.

ArcGIS was used to determine if plots overlapped or crossed the boundary lines of mitigation types; these plots were skipped. Plots were visited in the order they were generated. In total, we sampled the vegetation in 299 plots across ten mitigation areas (30 per mitigation area in all but Wet Buf Inf, which had 29 plots). No plots were established in mitigation area Gr/Herb Wet Buf as the performance standards for this mitigation area included a species list for the entire area.

Establishing Plots in the Field

Plot centers were located in the field using a Garmin GPS unit. The locations of the sampling points were not physically marked in the field to avoid subsequent management bias. At each

plot center, a 9.3 m2 (100 ft2) circular plot was used determine woody species density and tree/shrub percent cover, and a 1 m2 (10.76 ft2) circular plot was used to measure herbaceous species percent cover (Figure 2).

The Year 1 Monitoring Plan suggests establishing new temporary sampling points or adopting a rotating panel (a combination of permanent and temporary sampling points) for future monitoring. The approach for subsequent years will be determined when we prepare the Year 2 Monitoring Plan.

Woody Species Density

In accordance with the Wetland Vegetation Performance Standards (2.1, 2.2, 2.4) and Wetland Buffer Vegetation Performance Standards (5.2, 5.3), a woody species count was performed in all mitigation areas and density was calculated based on the area sampled.

In each 9.3 m2 plot, all living woody species were identified and added to the woody species density count for that plot. All plants were tallied, regardless of nativity or wetland status.

Woody species were separated into two strata, shrubs and trees. Seedlings of two species, black cottonwood, Populus balsamifera ssp. trichocarpa and pacific willow, Salix lucida were present in high density patches in some mitigation areas. These seedlings were categorized into their respective form, tree for P. balsamifera ssp. trichocarpa and shrub for S. lucida, for calculating percent cover of each stratum type. To more accurately estimate the density of woody species in each area, seedlings below two feet in height were not included in calculating woody species densities. Including the patches of densely crowded seedlings would not give an accurate representation of the woody species currently on site. Furthermore, the intense competition among the seedlings will ultimately result in only select individuals surviving. Subsequent monitoring will show how these seedlings establish in these areas and contribute to woody species density and percent cover upon maturity.

Individual plants with vegetative parts (branches, leaves, stems, etc.) extending into the plot were included in cover estimates, but it was noted that the plant was not rooted within the plot and it was not counted in the woody species density.

Woody Species Cover

In accordance with Structural Complexity Performance Standard 4.2, the percent cover of woody species was sampled in mitigation areas F Wet Enh, F Wet Est, F Wet Enh Inf, Sc-Sh Wet Enh, Sc-Sh Wet Est, Em Wet Enh, and Shor Em Wet Enh.

In each 9.3 m2 plot, all living woody species were identified and their collective cover estimated using a ‘bird’s eye view’. Cover classes were used to simplify and accelerate data collection in the field (Daubenmire 1959). The cover classes used were as follows:

● <1% (midpoint = 0.5%) ● 1-5% (midpoint = 3%) ● 5-15% (midpoint = 10%) ● 15-25% (midpoint = 20%) ● 25-50% (midpoint = 38%) ● 50-75% (midpoint = 63%) ● >75% (midpoint = 88%)

Individual plants with vegetative parts (branches, leaves, stems, etc.) extending into the plot were included, but it was noted that the plant was not rooted within the plot and it was not counted in the woody species density.

Emergent Wetland Vegetation Cover

In accordance with the Wetland Vegetation Performance Standards (2.2, 2.3, 2.4) and Structural Complexity Performance Standard 4.2, percent cover of herbaceous species was sampled in mitigation areas F Wet Enh, F Wet Est, F Wet Enh Inf, Sc-Sh Wet Enh, Sc-Sh Wet Est, Em Wet Enh, and Shor Em Wet Enh.

Herbaceous species were recorded within the 1 m2 plot at each location. All live plants were identified to species, regardless of nativity or wetland status, and their percent cover estimated using the cover classes described above.

Since cover was estimated using cover classes, we assigned each species of tree, shrub, and herb in each plot to the midpoint of its cover class as noted above. The midpoints for individual species were summed to yield a total cover for each stratum (tree, shrub, herb) and for all vegetation. Overlapping species canopies, as well as stratum layers, allow for percent cover to exceed 100%.

Since the Wetland Vegetation Performance Standards are based on native herbs, the herb stratum was further subdivided into native and non-native aspects.

Species List for Buffer Area (Gr/Herb Wet Buf)

In accordance with the Wetland Buffer Vegetation Performance Standard 5.1, the Gr/Hern Wet Buf was surveyed for occurrence of plant species seeded/planted.

Invasive Species Monitoring

In accordance with the Noxious Weed and Invasive Species Performance Standards (7.1, 7.2, 7.3, 7.4), a walkthrough of mitigation areas to assess noxious weeds and invasive species was performed in September, 2018. In each mitigation area, the following noxious weeds and invasive species were identified and their locations recorded:

● Rubus armeniacus ● Rubus laciniatus ● Cytisus scoparius ● Cirsium arvense ● Cirsium vulgare ● Carduus nutans ● Onopordum acanthium ● Iris pseudacorus ● Phalaris arundinacea ● Lythrum salicaria ● Lysimachia vulgaris

Each species was assessed using the same cover classes used for vegetative monitoring. Species locations were documented on a Trimble GPS (Figure 4). The subsections of each mitigation area were aggregated for a total percent cover (Table 4). For Lythrum salicaria, the

bio-control trial area surrounding Shoveler’s Pond (see as-built plan to identify bio-control trial area) was not included.

Photo-Documentation

A photograph was taken as a record of the conditions at each plot.

Habitat Structures

The Habitat Structures Performance Standard (6.1) was not formally assessed as it was assumed that the approval of the as-built plan verified that these structures were installed.

How Is the Site Developing?

The Union Bay Natural Area mitigation site has shown mixed results after year one monitoring. The site is complex, with 11 different mitigation areas and a wide range of performance standards. As this is only year one of monitoring, sites are still developing into their intended habitats.

A mortality count was performed after the vegetation monitoring for year one was conducted. A high mortality of installed plants was observed during counts performed by WSDOT and UWBG personnel in September, 2018. To address this deficiency an additional 20,000 plants were installed by the contractor (Table 5). This will ultimately raise woody species density in mitigation areas replanted. Irrespective of the new plantings, the forested wetland enhancement areas (F Wet Enh, F Wet Enh Inf) and the buffer mitigation areas (Wet Buf Enh, Wet Buf Inf, and Red Den Wet Buf) met performance standards for woody species density.

A high amount of herbicide damage was observed on both installed and existing native vegetation (Photo 1), suggesting drift from noxious and invasive species control. Plants highly damaged were marked for replanting during the mortality counts.

No unknown regulated noxious weeds were detected during the walk-through inspection. Known designated Class B and C noxious weeds at the project site are garden loosestrife (Lysimachia vulgaris) and purple loosestrife (Lythrum salicaria). Flowering purple loosestrife plants were found in each mitigation unit except in Sc- Sh Wet Est. Garden loosestrife was found in low abundance in mitigation areas F Wet Enh Inf, Shor Em Wet Enh, Wet Buf Enh, Wet Buf Inf, Red Den Wet Buf, and Gr/Herb Wet Buf (Figure 4).

The combined cover of non-native blackberries (Rubus armeniacus and R. laciniatus), Scotch broom (Cytisus scoparius), thistles (Cirsium arvense, C. vulgare, Carduus nutans, and Onopordum acanthium), and yellow-flag iris (Iris pseudacorus) only exceeded 10 % cover in the Em Wet Enh and Gr/Herb Wet Buf mitigation areas (Table 4). Two of these species (Rubus laciniatus, Cytisus scoparius) were not detected anywhere on site. All non-shoreline mitigation areas had <25% cover of reed canary grass, Phalaris arundinacea. However, the shoreline emergent wetland enhancement areas (Shor Em Wet Enh) had 68% cover (Table 4).

Management Needs

Forested Wetland Establishment, Enhancement and Infill

Under the structural complexity performance standard, mitigation areas intended to be forested wetlands (F Wet Enh, F Wet Est, F Wet Enh Inf) should be dominated by the tree stratum. Currently, all forested wetland mitigation areas are dominated by the shrub stratum (Table 1). However, the installed trees are still young, and therefore will require time to reach sizes that create a tree stratum dominated habitat. The F Wet Enh and F Wet Enh Inf mitigation areas meet woody species density requirements (Table 2). The F Wet Est mitigation area does not meet density, currently at 3.6 plants/100 ft². With additional woody species installed in this area post vegetation monitoring (September 2018), this performance standard should be reached. Management of all the forested wetland mitigation areas require treatment of individual Lythrum salicaria plants detected in each area. Additionally, treatment of Phalaris arundinacea is needed in the F Wet Enh and F Wet Enh Inf mitigation areas, and treatment of individual Lysimachia vulgaris plants is needed in the F Wet Enh Inf mitigation area.

Emergent Wetland Enhancement

The emergent wetland enhancement area (Em Wet Enh) should be dominated by herbaceous emergent species with at least 30% cover. This area is currently dominated by herbaceous cover, but most of it is non-native species (Table 1). Additional emergents planted post vegetation monitoring (September 2018) should help to increase native herbaceous cover, however additional plants may need to be installed depending on survival. The Em Wet Enh area does not meet woody species density requirements (Table 2). As with emergents, additional woody species were planted post vegetation monitoring (September 2018) and should help to increase the woody species density. Again, this will depend on the survival of subsequent planting. The Em Wet Enh mitigation area requires treatment of individual Lythrum salicaria plants, as well as control for Phalaris arundinacea. This mitigation area also needs to be managed to reduce the cover of Cirsium arvense, Cirsium vulgare, and Rubus armeniacus to reduce cover of these select invasive species to be below 10% total cover, as the

current estimate is 11.5% cover (Table 4). In several areas within the Em Wet Enh mitigation area, R. armeniacus grew in between existing vegetation which will require careful targeted herbicide application.

Scrub-Shrub Wetland Enhancement and Establishment

The scrub-shrub wetland establishment (Sc-Sh Wet Est) is filling in well with native emergents and exceeds requirements for herbaceous cover (Photo 2). However, herbaceous cover surpasses that of shrubs in both the Sc-Sh Wet Est and scrub-shrub wetland enhancement (Sc- Sh Wet Enh) (Table 1). Additional planting in the Sc-Sh Wet Enh should increase shrub stratum cover as well as woody species density, depending on survival. Live staking in the Sc- Sh Wet Est was not successful. This area should be reconsidered for scrub-shrub habitat, as herbaceous emergents are providing quality habitat without the woody cover. The Sc-Sh Wet Enh mitigation area requires treatment of individual Lythrum salicaria plants.

A high density of recruitment seedlings of black cottonwood, Populus trichocarpa, and Pacific willow, Salix lucida, were observed in the Sc-Sh Wet Enh and Sc-Sh Wet Est mitigation areas. While natural recruitment of native species is generally encouraging, areas intended to remain as scrubshrub may require control of these species to prevent them from becoming forested wetlands.

Shoreline Emergent Wetland Enhancement

The shoreline emergent wetland enhancement (Shor Em Wet Enh) meets requirements for cover to be considered emergent wetland habitat, though it has a high density of non-native reed canarygrass, Phalaris arundinacea (Table 1, 4). This area should be managed for the Phalaris arundinacea as well as individual Lythrum salicaria and Lysimachia vulgaris plants detected (Figure 4). The Shor Em Wet Enh does not meet woody species density. Live stakes did not survive in this area.

Management should focus on weed suppression and adding native emergent species rather than attempting to increase woody species density.

Wetland Buffer Areas

All wetland buffer areas met requirements for woody species densities (Table 2). All wetland buffer mitigation areas need to be managed for Lythrum salicaria and Lysimachia vulgaris. Individual plants of both species were detected in all wetland buffer mitigation areas (Figure 4). All wetland buffer mitigation areas except the Reduced Density Wetland Buffer (Red Den Wet Buf) also need to be managed for control of Phalaris arundinacea (Table 4).

The seed mix of the Grass/Herb Wetland Buffer (Gr/Herb Wet Buf) did not germinate as planned. The only species detected in this mitigation area specified in the design were Lupinus lepidus and Achillea millefolium with negligible cover for the site. Instead this mitigation area has a high amount of non-native invasive species including Rubus armeniacus, Cirsium arvense, C. vulgare, Carduus nutans, Onopordum acanthium and Iris pseudacorus that exceeded 10% total cover of the mitigation area and estimated to be 13% (Table 4). This area also had Phalaris arundinacea, and individual Lythrum salicaria and Lysimachia vulgaris plants (Table 4). This mitigation area will need to be managed for these invasive species. Without successful germination of the native seed mix applied, it is suggested to plant container plants of herbaceous species in this mitigation area.

Results for Performance Standard 1 (Hydrologic Performance)

1.1. As-built Documentation

1.2. Wetland Hydrology

Three hydrology monitoring visits occurred between March 22, 2018 and April 19, 2018 (Photo 3, Photo 4). The hydrology monitoring visits found that the wetland establishment areas met Performance Standard 1.2.

Results for Performance Standard 2 (Wetland Vegetation)

2.1. Forested habitat (F Wet Enh , F Wet Est , F Wet Enh Inf ), scrub- shrub habitat (Sc-Sh Wet Enh ) and shrub patches in emergent habitat (Em Wet Enh ): Planted native wetland woody species will achieve an average density of at least four plants per 100 square feet in planted zones of F Wet Enh and F Wet Enh Inf combined, F Wet Est , Sc-Sh Wet Enh S1, and shrub patches within Em Wet Enh

Mitigation areas F Wet Enh and F Wet Enh Inf are combined in this performance standard but differ in areal extent. The mean value was weighted for each area by its areal extent (i.e., 59% F Wet Enh , 41% F Wet Enh Inf ). The combined area met this performance standard as the average was 4.0 native wetland woody plants per 100 square feet (Photo 5, Table 2). F Wet Enh would have met this standard on its own (5.2 plants) and F Wet Enh Inf had 2.3 plants per 100 square feet.

Mitigation area F Wet Est did not meet this performance standard as the average was 3.6 plants per 100 square feet.

Mitigation area Sc-Sh Wet Enh did not meet this performance standard as the average was 2.3 plants per 100 square feet.

Mitigation area Em Wet Enh did not meet this performance standard (4 plants per 100 square feet of shrub patches, or 1 plant per 100 square feet across the entire mitigation area) as the average was 0.9 plants per 100 square feet.

2.2. Scrub-shrub wetland establishment area (Sc-Sh Wet Est ): Native wetland woody species will achieve an average density of at least 1.2 plants per 100 square feet in Sc- Sh Wet Est . Cover of native, wetland emergent vegetation will provide at least 25 percent cover in Sc-Sh Wet Est .

Mitigation area Sc-Sh Wet Est did not meet the woody plant density performance standard as the average was 0.7 plants per 100 square feet (Table 2). High mortality of live stakes was observed in this mitigation area.

Sc-Sh Wet Est met the cover performance standard with 36% cover of native herbs (Table 1).

2.3. Emergent wetland habitat (Em Wet Enh ): Cover of native emergent wetland vegetation will be measured and at least 30 percent will be native emergent cover in Em Wet Enh .

Mitigation area Em Wet Enh E1 did not meet the cover performance standard as native herbs provided 7% cover (Table 1).

2.4. Emergent shoreline wetland habitat (Shor Em Wet Enh ): Cover of native wetland vegetation (herbaceous and planted woody) will be measured. At least 15 percent cover will be native emergent vegetation and planted native woody species will achieve an average density of at least 1 plant per 100 square feet in Shor Em Wet Enh .

Mitigation area Shor Em Wet Enh met the cover performance standard as native herbs provided 52% cover (Table 1). This is due to the high density of cattail, Typha latifolia, on site.

However, this area is also heavily invaded by reed canarygrass, Phalaris arundinacea and needs further maintenance to control this species and encourage native growth.

Mitigation area Shor Em Wet Enh did not meet the woody plant density performance standard as the average was 0.3 native wetland woody plants per 100 square feet (Table 2). High mortality of live stakes was observed in this mitigation area (Photo 6).

Results for Performance Standard 4 (Structural Complexity)

4.2. For all wetland habitats, installed vegetation is consistent with the proposed vegetation type as identified in the wetland mitigation planting plans.

The shrub stratum had the highest percent cover for all forested wetland mitigation areas (F Wet Enh, F Wet Est , and F Wet Enh Inf ) (Table 1). No intended forested wetland mitigation areas currently have greater than 30% cover of trees. This stratum will most likely develop as the site continues to become established. Average tree cover was 4% in F Wet Enh , 6% in F Wet Est , and 26% in F Wet Enh Inf (Table 1).

Scrub-shrub wetlands are where shrubs are the dominant life form with at least 30 percent areal coverage. Mitigation areas Sc-Sh Wet Enh and Sc-Sh Wet Est are both currently dominated by herbs, and neither has shrub cover above 30% (Table 1). The cover of trees and shrubs in these mitigation areas is heavily impacted by a high density of recruitment seedlings of Populus balsamifera ssp. trichocarpa and Salix lucida (Photo 7).

Emergent wetlands are where emergent plants are the tallest life form with at least 30 percent areal coverage. The emergent wetland mitigation area Em Wet Enh met this performance standard with 31% herb cover, though most of this (25%) was non-native species (Table 1). The shoreline emergent wetland mitigation area Shor Em Wet Enh met this performance standard with 79% herb cover, 52% of which was native species.

Results for Performance Standard 5 (Wetland Buffer Vegetation)

5.1. Grass/Herbaceous wetland buffer (Gr/Herb Wet Buf ): Native seed mix or plantings will be accounted for in year one of monitoring with a walk- through identifying species present and creating a species list.

A walkthrough of the Grass/Herb Wetland Buffer was conducted on August 23, 2018. The only species detected in this mitigation area specified in the design were Lupinus lepidus and Achillea millefolium with negligible cover for the site (Table 3). A high amount of cover of invasive species was observed in this wetland buffer area (Photo 8).

5.2. Wetland buffer (Wet Buf Enh ): Native woody species will achieve an average density of at least four plants per 100 square feet. Mitigation area Wet Buf Enh met the woody plant density performance standard with an average of 4.5 native woody plants per 100 square feet (Table 2).

5.3. Reduced density wetland buffer (Red Den Wet Buf ) and wetland buffer infill (Wet Buf Inf ): Native woody species will achieve an average density of at least 1.2 plants per 100 square feet.

Mitigation area Red Den Wet Buf4 met the woody plant density performance standard with an average of 2.3 native woody plants per 100 square feet (Table 2).

Mitigation area Wet Buf Inf met the woody plant density performance standard with an average of 2.6 native woody plants per 100 square feet.

Results for Performance Standard 6 (Habitat Structures)

6.1. Installation of habitat structures will be verified and an as-built plan will document that all habitat structures were installed.

This performance standard was documented in by WSDOT’s as-built plan. An example of a habitat structure is shown in Photo 9.

Results for Performance Standard 7 (Noxious Weeds and Invasive Species)

7.1.1. Washington State-listed or King County-listed Class A weeds designated for control by the County weed board must be eradicated.

No unknown regulated noxious weeds were detected during the walk-through inspection.

7.1.2. Designated Class B or C by King County will be controlled annually to prevent seed production and to prevent dispersal of propagative parts that are capable of starting new plants.

Known designated Class B and C noxious weeds at the project site are purple loosestrife (Lythrum salicaria) and garden loosestrife (Lysimachia vulgaris).

Purple loosestrife had low cover (1-5%) in mitigation areas Shor Em Wet Enh and Gr/Herb Wet Buf5, and very low cover (<1%) in F Wet Enh, F Wet Est, F Wet Enh Inf, Sc- Sh Wet Enh, Em Wet Enh E1, Wet Buf Enh B1, and Wet Buf Inf. No purple loosestrife was observed in Sc-Sh Wet Est (Table 4).

Garden loosestrife had very low cover (<1%) in mitigation areas F Wet Enh Inf, Shor Em Wet Enh, Wet Buf Enh, Wet Buf Inf B3, Red Den Wet Buf, and Gr/Herb Wet Buf (Photo 10; Table 4). No garden loosestrife was observed in F Wet Enh, F Wet Est, Sc-Sh Wet Enh, Sc-Sh Wet Est, or Em Wet Enh.

GPS coordinates of individuals of both species were recorded for future management (Figure 4).

7.2.1. The combined cover of non-native blackberries (Rubus armeniacus and R. laciniatus), Scotch broom (Cytisus scoparius), thistles (Cirsium arvense, C. vulgare, Carduus nutans, and Onopordum acanthium), and yellow-flag iris (Iris pseudacorus) will not exceed 10 percent cover, collectively, in the established or enhanced wetland and buffer areas.

All areas except Em Wet Enh and Gr/Herb Wet Buf meet this standard (Table 4). Rubus laciniatus and Cytisus scoparius were not detected in any areas, and Carduus nutans and

Onopordum acanthium were only detected in mitigation area Gr/Herb Wet Buf. Iris pseudacorus was the only one of these species detected in mitigation area Sc-Sh Wet Est.

Total cover of invasive species of concern in Em Wet Enh was estimated at 11.5%. This was primarily due to the high amount of Rubus armeniacus. In several areas with pre-existing trees and shrubs, Rubus armeniacus grew in between existing vegetation.

Mitigation area Gr/Herb Wet Buf had 13% total cover of these species, due primarily to Rubus armeniacus, Cirsium arvense, Cirsium vulgare, and Iris pseudacorus (Table 4). This mitigation area likely had a higher amount of non-native species since mulch couldn’t be applied over the native seeding mix. It will therefore require more focused management of these species.

7.2.2. Non-native knotweeds identified on the King County noxious weed list (Polygonum cuspidatum, P. polystachyum, P. bohemicum, P. sachalinense) will be eradicated.

No non-native knotweeds on the King County noxious weed list (Polygonum cuspidatum, P. polystachyum, P. bohemicum, P. sachalinense) were detected during the walk-through inspection.

7.2.3. Reed canarygrass (Phalaris arundinacea) will not exceed 25 percent cover in the non- shoreline wetland mitigation areas, and not exceed 50 percent cover in the shoreline wetland mitigation areas.

All non-shoreline mitigation areas had much less than 25% cover of reed canarygrass (Table 4).

The shoreline mitigation area (Shor Em Wet Enh) had more than 50% cover (Photo 11; Table 4). Further weed control is needed along the shoreline to control growing populations.

7.3.1. No purple loosestrife, Lythrum salicaria, flowers will be allowed to develop seed at Year 1; flowers will not be present within wetland enhancement areas at time of monitoring in early to mid-August. Cover will be assessed quantitatively to determine a baseline for purple loosestrife.

Several individual purple loosestrife plants were found flowering in each mitigation unit except in Sc-Sh Wet Est (Photo 12). GPS coordinates of these individuals were recorded for future management (Figure 4). No mitigation area had a total percent greater than 5% (Table 4).

7.4.1. At Year 1, after initial control, cover will be assessed quantitatively to determine a baseline for Garden loosestrife (Lysimachia vulgaris).

Garden loosestrife was present at low levels (<1% cover) in mitigation areas F Wet Enh Inf, Shor Em Wet Enh, Wet Buf Enh, Wet Buf Inf, Red Den Wet Buf, and Gr/Herb Wet Buf (Table 4). GPS coordinates of these individuals were recorded for future management (Figure 4).

What Is Planned For This Site?

Post vegetation monitoring, survivorship counts by WSDOT personnel and UWBG staff occurred in August 2018. Mortality counts indicated necessary replanting. In September 2018, an additional 20,233 plants were installed, including 14,258 woody species, 6,000 emergents and 1,600 forbs (Table 5). The replanting should aid mitigation sites currently not meeting performance standards related to woody plant density and herbaceous cover.

A high percentage of installed plants were observed to have damage from herbicide drift. Careful application of herbicides is necessary to limit any further damage to native vegetation. Management should focus spraying herbicides only on days with minimal winds to avoid further damage to native species installed.

Further monitoring and management is recommended for the scrubshrub wetland mitigation areas (Sc-Sh Wet Enh and Sc-Sh Wet Est) mitigation areas with high densities of black cottonwood seedlings (Photo 13). Mitigation areas Sc-Sh Wet Enh and Sc-Sh Wet Est are intended to serve as scrubshrub wetland habitat and therefore control of black cottonwood seedlings may be needed to avoid these mitigation areas from becoming forested wetlands.

Ongoing maintenance will be needed to control populations of noxious and invasive species, especially in the emergent wetland enhancement mitigation areas (Em Wet Enh) and the grass/herbaceous wetland buffer (Gr/Herb Wet Buf) which have an estimated cover greater than 10% of listed noxious and invasive species (Table 4).

Individual purple loosestrife and garden loosestrife plants should be eradicated to prevent spread (Figure 4). However, no loosestrife management should occur in the bio-control area around Shoveler’s Pond, where Galerucella beetles are active and controlling purpose loosestrife.

The shoreline wetland enhancement mitigation area (Shor Em Wet Enh) will need to be monitored and maintained to suppress populations of reed canarygrass which currently covers an estimated 50-75% of the mitigation area.

WSDOT and UW continue to coordinate on site establishment to ensure the site will be a success.

Appendix 1 – Additional Figures

Figure 3. Plot center locations. 30 plots total were monitored for each aggregated mitigation type.

Figure 4. Locations of noxious and invasive species located during walkthrough.

Appendix 2 – Data Tables Table 1. Average Percent Cover

Average cover (%), by nativity and stratum, per plot. Performance standard 2 (Wetland Vegetation) relates to native herbaceous (emergent) species, so native species are divided into tree, shrub, and herbaceous strata. For native herbaceous plants, cover values that currently meet the performance standard are shown in underlined bold and those that do not meet it are shown in red. Performance standard 4 (Structural Complexity) relates to the stratum (tree, shrub, herb) that dominates the cover, regardless of nativity. In each mitigation area, this stratum is highlighted in grey.

Mitigation Tree Shrub Native Herb Non- Herb Total Area Native (Native & Herb Non- Native)

Performance Data Standard

F Wet Enh 6 33 - 9 8 17 56

F Wet Est 4 17 - 4 2 6 28

F Wet Enh 26 57 - 23 11 35 118 Inf

Sc-Sh Wet 15 19 - 8 17 25 59 Enh

Sc-Sh Wet 9 16 25 36 8 44 70 Est

Em Wet 5 22 30 7 25 31 58 Enh

Shor Em 3 5 15 52 28 79 88 Wet Enh

Table 2. Average Woody Plant Density

Average density of woody plants per plot (100 ft2). Performance standard 2 (Wetland Vegetation) relate to native wetland woody plants so native species are divided into wetland (i.e., those with wetland status FAC, FACW, or WET) and upland (FACU, UPL, #N/A) categories. Performance standard 5 (Wetland Buffer Vegetation) relates to native woody plants regardless of wetland status. For native wetland woody plants and all native woody plants, densities that currently meet the performance standard are shown in underlined bold and those that do not meet it are shown in red.

Mitigation Native Native Native Non- Total Area Wetland Upland (Wetland & Upland) Native

Performance Data Performance Data Standard Standard

F Wet Enh - 5.2 0.1 - 5.4 0.5 5.9

F Wet Enh - 2.3 0.2 - 2.5 1.2 3.7 Inf

F Wet Enh & F 4 4.0 0.1 - 4.2 0.8 5.0 Wet Enh Inf combined 1

F Wet Est 4 3.6 0 - 3.6 0 3.6

Sc-Sh Wet Enh 4 2.3 0.2 - 2.5 0.3 2.9

Sc-Sh Wet Est 1.2 0.7 0 - 0.7 0 0.7

Em Wet Enh 1 0.9 0.2 - 1.1 0.9 2.0

Shor Em Wet 1 0.3 0 - 0.3 0.6 0.9 Enh

Wet Buf Enh - 4.3 0.2 4 4.5 1.5 6.0

Wet Buf Inf - 2.3 0.2 1.2 2.6 3.7 6.3

Red Den Wet - 1.9 0.4 1.2 2.3 1.2 3.5 Buf

1 Mitigation areas F Wet Enh F1 and F Wet Enh Inf F3 are combined in this performance standard but differ in areal extent. We weighted the mean value for each area by its areal extent (i.e., 59% F Wet Enh F1, 41% F Wet Enh Inf F3).

Table 3. Species List of the Grassland/Herbaceous Buffer

The following species were identified in the grassland/herbaceous buffer (mitigation area Gr/Herb Wet Buf ).

Species Common name Life Form Nativity Seeded?

Achillea millefolium yarrow Herb Native Seeded

Lupinus lepidus broadleaf lupine Herb Native Seeded

Table 4. Noxious Weeds and Invasive Species

Cover of invasive species, by mitigation area. Cover was estimated separately for each species using the same cover classes as for other cover estimates in this project; the midpoint of the class is reported here. Performance standard 7.2.1 specifies that the combined cover of 8 invasive species of concern (top of the list) will not exceed 10%. Performance standard 7.2.3 specifies that Phalaris arundinacea will not exceed 25% cover in non-shoreline areas and will not exceed 50% in mitigation area Shor Em Wet Enh L1. Values that currently meet the performance standard are shown in underlined bold and those that do not meet it are shown in red. Abundance information for Lythrum salicaria and Lysimachia vulgaris will be used to determine a baseline for each species.

Shor Red Gr/He F Wet Sc-Sh Sc-Sh Em Em Wet Wet Den rb F Wet F Wet Enh Wet Wet Wet Wet Buf Buf Wet Wet Species Enh Est Inf Enh Est Enh Enh Enh Inf Buf Buf

Rubus armeniacus 3 0.5 3 3 0 10 3 3 3 3 3

Rubus laciniatus 0 0 0 0 0 0 0 0 0 0 0

Cytisus scoparius 0 0 0 0 0 0 0 0 0 0 0

Cirsium arvense 0.5 0.5 0.5 0.5 0 0.5 0.5 0.5 0.5 0.5 3

Cirsium vulgare 0.5 0.5 0.5 0.5 0 0.5 0.5 0.5 0.5 0.5 3

Carduus nutans 0 0 0 0 0 0 0 0 0 0 0.5

Onopordum acanthium 0 0 0 0 0 0 0 0 0 0 0.5

Iris pseudacorus 0.5 0.5 0.5 0.5 0.5 0.5 3 0.5 0.5 0.5 3

TOTAL 4.5 2 4.5 4.5 0.5 11.5 7 4.5 4.5 4.5 13

Phalaris arundinacea 0.5 0 3 0 0 0.5 68 3 0.5 0 0.5 Lythrum salicaria 0.5 0.5 0.5 0.5 0 0.5 3 0.5 0.5 0.5 3

Lysimachia vulgaris 0 0 0.5 0 0 0 0.5 0.5 0.5 0.5 0.5

Table 5. Replanting Totals

The following species were planted in Autumn 2018. These plants were therefore not included in the Year 1 monitoring, which occurred in Summer 2018. This summary does not document in which mitigation areas each species was planted.

Species Common Name Total

Shrubs

Cornus sericea Red Osier Dogwood 3067

Crataegus douglasii Black Hawthorn 350

Lonicera involucrata Black Twinberry 230

Malus fusca Pacific Crabapple 1159

Physocarpus capitatus Pacific Ninebark 526

Ribes divaricatum Spreading Gooseberry 441

Ribes lacustre Black Gooseberry 670

Rosa nutkana Nootka Rose 665

Rosa pisocarpa Clustered Rose 951

Rubus spectabilis Salmonberry 963

Salix sitchensis Sitka Willow 2743

Spiraea douglasii Douglas Spirea 617

Symphoricarpos albus Common Snowberry 1115

Total shrubs 13,497

Trees

Acer macrophyllum Big leaf Maple 20

Alnus rubra Red Alder 20

Fraxinus latifolia Oregon Ash 152

Picea sitchensis Sitka Spruce 52

Pinus contorta Shore Pine 52

Populus tremuloides Quaking Aspen* 60

Pseudotsuga menziesii Douglas Fir 21

Quercus garryana Garry Oak* 195

Salix lucida Pacific Willow 40

Thuja plicata Western Red Cedar 149

Total trees 761

Emergents

Carex obnupta Slough Sedge 1596

Carex stipata Sawbeak Sedge 834

Deschampsia cespitosa Tufted Hairgrass 234

Eleocharis palustris Common Spikerush 234

Juncus acuminatus Tapertip Rush 234

Juncus tenuis Slender Rush 834

schoenoplectus acutus Hardstem Bulrush 234

Scirpus microcarpus Small-fruited Bulrush 1200

Juncus ensifolius Swordleaf Rush 600

Total emergents 6,000

Forbs

Achillea millefolium Common Yarrow 280

Allium cernuum Nodding Onion 120

Aster subspicatus Douglas Aster 160

Camassia quamash Common Camas 160

Erigeron speciosus Showy Fleabane 160

Fragaria virginiana Virginia Strawberry 240

Lupinus lepidus Pacific Lupine 240

Potentilla gracilis Spreading Cinquefoil 240

Total forbs 1,600

Grand Total All Plants 20,233

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