ApprovedNativeVegetationPlan.pdfM d
Mitigation Plan
Edmonds, WA
Prepared for:
Kent Halverson I Halverson Construction Group LLC
12515 Willows Road NE
Suite 220
Kirkland, WA 98034
Prepared by:
Suzanne Tomassi, MSc, CWB, PWS
Senior Biologist
Owner:
MeadowView Estates
Avia Environmental Consulting
Table of Contents
1 Introduction .. ................... ........, ......... ......... ......... ........, ......... ......... .,....,., ..,....,. ...,........1
2 METHODS ................. ......... ......... ... ............................ . ......... ........., ..,.,.....,...,...,, ,...,.... ,..........,
2
2.1 Existing Documentation Review ............................ ....................................................... ., .....»......2
2.2 Fieldwork ........ ......... ......... ......... ................... ......... ......... .,....... ,........ ......... .,..........2
3 EXISTING CONDITIONS .................... ................... .......... ...... ... ......... ......... .............. .,.,.. ...,........,3
3.1 Project Vicinity ............................... ......». ...... ......... .............,..............., ........, ............3
3.2 Study Area ....................... ......... ......,... ......... ......... .....,... ......... ..................... .,., 3
4 CRITICAL AREAS........ .».... ......... ........ ......... ........................ .............
.............. ......... ............3
5 HABITAT ASSESSMENT ................................... ......... ..........,........ ,......,....,..,........,,.... .......»....4
5.1 Study Area Habitat Function ......................... ... ....,.,.. ......... ,.....,., ,.»...........................,...4
5.2 Landscape -level Habitat Function .......... ...................... ............. ...., ......... ......... ...,....,...6
5.3 Species of Local Importance .......................... ......... ....., ........ ...,..... ......... ......... ,,,...,,,...7
5.3.1 Bald Eagle. ..,...., ...... ......... ................................................... ......... .....,... .........,..7
5.3.2 Osprey ................... ......... .......... ........ .................... ......... ......... ......... ......... ............7
5.3.3 Great Blue Heron ........................ .,,......,.,............».................... ,.....,..,......»„................... .,,......8
5.3.4 Pileated Woodpecker ...... ......... ......... ......... ............... .................... ...... ...,...,..8
5.3.5 Fish .................................. ....... ........ ......... .....».,...... ......... .,..... .,....... 8
6 Project Description .... ........ . ......... .................... ......... ............ ....................... ....... ......... ...........8
7 Vegetation Management Impacts ........................ ,.......____ ......... .... ........ ......... ....,.......9
7.1 Direct Impacts .................................... ....... ..................... 9
7.2 Indirect and Cumulative Impacts ....... ......... ........... ....... ......... ........ ......... ,,.9
8 Mitigation ................................................... ................. ,.....,............. ... .....,, ......... ........, ...........9
8.1 Mitigation Sequencing .........„............. .................... ......... ........ ........, .......... ,9
8.2 Mitigation Plan.....__ ....... ......... ......... ...».,... .....,...,....,..... 10
8.2.1 Goals and Objectives .................. ......,,.,....,...., ........, ,..,..,., ......... ..........10
8.2.2 Installation ....................... ................... ......... ......... .............. ,........ ..........,.,...., 11
8.2.3 Maintenance ..................................... ......... ......... ......... .................. ......... .........11
8.2.4 Performance standards...» ................... ......... .......... ......... ........ ......... ......... .»......,11
8.2.5 Monitoring Methods .................. ......... ..... ............. ... ......... ......... .................. .........12
8.2.6 General Work Sequence .. .......... ...... . ............. ............. ...... ......... ...............................12
8.2.7 Contingency Plan ............. ......... ......... ......... .»........ .....,,,. ......... .,,,..... ...,....» ...,.,...13
8.2.8 Planting Notes ............................ ......... ...... ......... .........13
REFERENCES»...................................................... _,......... ........,.. ,........ ,....... . ......... ..,........,........ .........14
April 4, 2016
INTRODUCTION
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This habitat assessment addresses the 2.52 -ac property located at 15620 72nd Avenue W in the City of
Edmonds (parcels 00513300002501 and 00513100002406) (Figures 1 and 2) and surrounding area. This
document contains information and analyses required by Edmonds Community Development Code
(ECDC) 23.90.020. The property is presently vacant single-family use and contains a newly renovated
house and associated driveway, garage, and landscaping. Four additional single-family residences are
proposed for the site.
This assessment was prepared by a Certified Wildlife Biologist based on a review of existing information
and a site investigation.
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Figure 1. Subject property vicinity map (from Google Maps).
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Figure 2. 2015 aerial photograph of subject property (from Google Maps)
2 METHODS
2.1 Existing Documentation Review
Publicly available documentation reviewed for this assessment includes Washington Department of Fish
and Wildlife (WDFW) Priority Habitats and Species (PHS) maps and guidances, WDFW SalmonScape
online maps, the Washington State Department of Natural Resources (DNR) Natural Heritage database,
Snohomish County online property information, City of Edmonds online maps, general information on
habitat types from Johnson and O'Neil (2001), and scientific literature.
2.2 Fieldwork
The biologist conducted a brief site visit on November 5, 2015, to discuss the subject property and
proposed actions with the project arborist and construction personnel. A second site visit was
conducted on November 19 and consisted of a detailed examination of vegetation, wildlife, and habitat
features on the site and surrounding area. Vegetative structure and composition were assessed and the
presence of wildlife species, sign, and habitat features were recorded. The property was examined for
the presence and sign of pileated woodpecker and other species of local importance.
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3 EXISTING CONDITIONS
3.1 Project Vicinity
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The project site is located near the northern boundary of the City of Edmonds, approximately 500 feet
east of the shore of Puget Sound (see Figure 1). Residential development surrounds most of the site,
with Meadowdale Beach Park approximately 500 feet to the north and several smaller parks and natural
areas nearby. The greater vicinity is a mix of high to low density residential development.
3.2 Study Area
The subject property totals 2.52 acres (109,650 sf) and five lots. It is presently unoccupied, with one
newly renovated home, garage, and driveway on one of the lots. A mix of native and non-native
landscaping surrounds the developed lot, and undergrowth and lower branches have been cleared from
the areas of proposed houses (Appendix A, Photo 1). The western portion of the site is a steep slope
down toward the Sound; the height of the trees in the area west of the existing house has been reduced
by topping (Appendix A, Photo 2). Thinly vegetated understory is the result of a past landslide on this
slope in this area. The landslide area is dominated by Himalayan blackberry and Scotch broom, with
scattered young and topped red alder, bigleaf maple, and Douglas fir. Sparse native understory species
in the area are beaked hazelnut, salal, and bracken fern. While this landslide area is located within the
boundaries of the study property, it is not included in the assessment or mitigation except insofar as it
may impact the bordering slopes and buffers.
The slope adjacent to the landslide area is forested with mature Douglas fir, western red cedar, and
bigleaf maple and has a dense understory of mostly native species (Appendix A, Photo 3). Table 1 lists all
vegetative species observed on the site during two field visits.
4 CRITICAL AREAS
The WDFW SalmonScape database depicts a stream with a salmon -bearing tributary (documented Coho
rearing habitat) in Meadowvale Beach Park (Appendix B). The mainstem of the stream (Lunds Gulch
Creek) is not shown as a salmon -bearing waterway, but the presence of salmon in a tributary implies the
presence of salmon in the downstream mainstem as well. The stream is approximately 1,000 feet from
the edge of the subject property at its closest point. It drains to Puget Sound northwest of the subject
property.
Lunds Gulch Creek and its adjacent riparian area are part of a WDFW PHS Biodiversity Corridor. The edge
of the corridor, as depicted on current PHS maps, is approximately 500 feet north of the subject
property (Appendix Q.
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The steep slope on the west side of the subject property is regulated as a geologically hazardous area
under ECDC 23.80 and is not further addressed in this report except as habitat. No other critical areas
were noted on or immediately adjacent to the property.
Table 1. Vegetative species recorded in the subject property.
Common name
Scientific name
...... ----
Trees
......................
Douglas fir
Pseudotsuga menziesii
Western red cedar
Thuja plicata .�........................................
Bileaf m
g maple
Acer macrophyllum
Red alder
Alnus rubra
Pacific madrone
Arbutus menziesii
_...w ..............
Black
Black cottonwood
__..........................
_............ _.
Populus balsamifera
Bitter cherry
�...............
.................................
Prunus emarginata
..........................
Shrubs
Himalayan blackberry
Rubus ameniacus
Evergreen blackberry
Rubus laciniatus
_. ry
Rubus spectabilis
......._............
Snowberry
.................... .........
_......... ............... .-__....
Symphoricarpos albus
................................
Red huckleberry
Vaccinium parvifolium
Beaked hazelnut �.........._
Corylus cornuta
..................
Osoberry
.........
Oemleria cerasiformis
Salal
Gaultheria shallon
.�... ...................
Cascara
�.................
........... .......... ...__
Rhamnus purshianus
........
English ivy
Hedera helix
English holly
..................................___.......
Ilex aquilfolium
Scotch broom _
Cytisus scopariu
Cherry laurel
Prunus laurocerasus
Herbs
Sword fern
Polystichum munitum
Bracken fern
Pteridium aquilinum
Fringecup
Tellima grandiflora
Pacific bleeding g hea rt
Dicentra formosa
Grasses.__..................................w-Poa
sp.
5 HABITAT ASSESSMENT
5.1 Study Area Habitat Function
Habitat in the project vicinity can be generally characterized as urban and mixed environs (Johnson and
O'Neil 2001). Native habitat on the site consists of mid -age to mature forest dominated by Douglas fir,
western red cedar, and bigleaf maple, with a dense understory of mostly native trees, shrubs, and
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herbaceous species (see Appendix A, Photo 3). Vegetation is structurally and compositionally complex
in some areas, providing high-quality habitat for birds and mammals common to the area. Wildlife of
the nearby shoreline and biodiversity corridor likely use the subject property to varying extents. Distinct
areas of varying quality on the property are described in the following paragraphs.
Vegetation in the areas of proposed residential development consists of mature conifers with little
remaining undergrowth or mid -story vegetation (see Appendix A, Photo 1). Habitat value is
consequently limited, consisting of nesting, perching, and foraging habitat for primarily canopy -dwelling
bird species.
The landslide area described in Section 3.2 is densely vegetated with invasive shrubs. The dominant
Himalayan blackberry is an aggressive invasive species, and little other vegetation can successfully
compete with it. It does, however, provide forage and cover for some species, such as white -crowned
sparrows. Remaining small snags on the edge of the clearing provide perching and foraging habitat for
woodpeckers and other birds (see Appendix A, Photo 2).
Undisturbed habitat on the forested slope is suitable for urban -adapted woodland species, including
common passerines and near -passerines such as black -capped and chestnut -backed chickadee, dark -
eyed junco, bushtit, song sparrow, Steller's jay, American robin, and crow; small mammals such as
squirrels, voles, and mice; and larger mammals such as raccoon, coyote, opossum, mountain beaver,
and deer. The canopy, mid -story, and understory provide potential nest sites for songbirds, near -
passerines, and raptors. Foraging opportunities are high in the native vegetative community.
Dead and decaying trees are abundant on the steep slope, as are logs and stumps. These habitat
features are valuable wildlife habitat components, particularly for woodpeckers and cavity -nesting birds.
Few of the trees, snags, and logs show sign of woodpecker use, however. Two cavities that may be used
for nesting by birds were noted on the site. Despite the paucity of woodpecker sign, three woodpecker
species were observed during the two site visits: downy woodpecker, red -shafted flicker, and pileated
woodpecker (see Section 5.3, below). Species and sign observed on the site during the November site
visits are listed in Table 2.
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Table 2. Wildlife species
identified on the study
site.
Common name
Scientific name
Observation
Habitat/location
._......�
_........_ W ......__
type
Birds
mm .
Song sparrow
....................
Melospiza melodia
Aural
_........ _....._
Forest understory
Black ca ed chickadee
pp
Poecile atncapillus
Visual
Forest midstory
Dark-eyed junco
Junco hyemalis
----------
Visual
Forest understory
Golden -crowned kinglet
Regulus satrapa
Visual
...................
Forest midstory and canopy
American goldfinch
Carduelis tristis
Aural
Forest canopy
Stellar's jay
_.
Cyanocitta stelleri
_ ........y
Aural
Forest midstory and canopy
American crow ........
Corvus brach rh nchos
.............. y
Visual
......._
�....._..
Forest canopyand fly -over
Pacific wren
I Troglodytes pacificus
_ _.... ..
_........... Visual
Forest understory
Bewick's wren
.....
Thryomanes bewickii
............
Visual
. .... .............. .
Forest understory
Anna's hummingbird
Calypte anna
............
Aural
Forest midstory
Great blue heron
-----------
Ardea herodias
Visual
-_........_.............
Forest canopy
Red -shafted flicker
.....M
tes auratus
Colapwwwwwwwww _
_.
............. Visual
.....
Forest midstory
______....... _...................
Pileated woodpecker
Dryocopus pileatus
Visual
Forest midstory and landslide
...Down
area snag
woo.._..
y dpecker
�.__ ........._.
Picoides pubescens
Visual
.......�� �...._ .. _.
Landslide area snag
Bald eagle
Haliaeetus leucocephalus
Visual
Conifer, adjacent property
Mammals
�.............._
.............._.......
Mountain beaver
p __.
ontia rufa
A lod._.._....
_...............
Burrows
Forested slope
Douglas squirrel
Tamiasciurus douglasii
Visual
mmmmmmm ..
Forest midstory
All vegetative communities within the study should be considered together in qualifying habitat value,
as their juxtaposition and interspersion create transitions zones that may attract wildlife beyond those
species supported by each habitat alone. This transitional habitat, or edge, has both positive and
negative impacts on wildlife. In general, edges support higher species richness than each block of
habitat they join. This increase in richness is most noticeable when the adjoining communities are very
different from one another. However, edges can also promote invasion by pest species into adjoining
habitat, particularly where they occur near urban areas. Nest depredation and brood parasitism are also
generally high in edge habitat. Creation of edge in urban areas is usually considered more harmful than
beneficial to wildlife.
Edges between vegetative communities on the subject property do not add substantial value to the
habitat as a whole. The edge between the development area and forested slope is define mainly by the
loss of under- and mid -story in the transition, and the edges surrounding the landslide area similarly
represent a loss of mid- and upper -story strata, as well as intruding Himalayan blackberry sprouts.
5.2 Landscape -level Habitat Function
Although the subject property is in a developed landscape, it is within approximately 500 feet of a large
forested PHS biodiversity corridor. The corridor is separated by roads and other residential
development from the subject property and its adjacent habitat. Thus, movement of mammals and
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herptiles across a larger landscape is probably limited, but most birds are less hindered by the lack of a
vegetated corridor than other species. Birds and mammals are likely to utilize the subject property as a
stop -over or forage area by individuals of larger wildlife populations in the corridor. Species whose
breeding requirements are completely met on the property could also breed where vegetation provides
nest and forage sites.
As a moderately sized habitat patch, the subject property habitat provides refuge value for wildlife in
this urbanized area. Generally, the larger the habitat fragment in an urban area, the greater species
richness it supports (Johnson and O'Neil 2001). Forest fragments surrounded by urban development are
vital to urban bird conservation, although they don't support the species that larger forests on the
outskirts of urbanizing areas can (Donnelly and Marzluff 2004). The vicinity as a whole is urban, and
specifically single-family residential. As a general rule, species diversity decreases and species densities
increase as urbanization increases (Johnson and O'Neil 2001). Density increases are largely the result of
exotic species thriving in urban areas, although the study site still supports a native wildlife community.
Of particular value on the subject property are the numerous snags and large conifers, which are
increasingly rare in urbanizing landscapes, and which enhance urban biodiversity by supporting a variety
of species in additional to common urban species.
5.3 Species of Local Importance
An area may be classified as a Fish and Wildlife Habitat Conservation Area if it has a primary association
with a State priority species, species with state or federal listing status (threatened, endangered, or
sensitive), or other species of interest (ECDC 23.90.010). These species are collectively referred to as
species of local importance.
WDFW PHS online data show no records of bird or mammal species of local importance on or within 0.5
mile of the subject property. The nearest PHS species occurrence is Dungeness crab, approximately 500
feet to the west in Puget Sound. Species of local importance that were observed or could potentially
occur in the vicinity of the subject property are addressed in the following sections.
5.3.1 Bald Eagle
WDFW (2015) PHS data show the nearest documented bald eagle nest site to be approximately 1.5
miles from the project site. WDFW-recommended management zones do not extend to the site. Bald
eagles are common foragers over Puget Sound. The study site itself contains no suitable bald eagle
foraging habitat. Tall conifers on the site could be used for perching at times and are potential nest
trees. Two bald eagles were observed perched in tall conifers between the subject property and the
Puget Sound shoreline during the November 19 site visit (Appendix A, Photo 4).
5.3.2 Osprey
The nearest documented PHS osprey occurrence is 0.6 mile from the subject property (WDFW 2015).
The species is common in the Puget Sound shoreline area, and individuals often perch in tall trees near
open water during foraging. Suitable foraging perch sites are present on the subject property. Future
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use of the property for nesting cannot be precluded, as the species regularly nests in the tops of tall
trees near open water. No nests were observed on or adjacent to the property during site visits.
5.3.3 Great Blue Heron
Great blue heron rookeries (colonial nesting sites) are usually located in tall trees near wetlands, lakes,
and other water bodies. The species is very common in western Washington year-round. In winter in
particular, the species is widespread, foraging both in aquatic and upland areas (Seattle Audubon
Society 2015). One individual was observed during the November 19 site visit landing in a tall deciduous
tree near the southwestern extent of the subject property.
5.3.4 Pileated Woodpecker
Pileated woodpeckers are fairly common in urban forests in the Puget Sound area. They occupy both
mature and second -growth forest (Lewis and Azerrad 2003). While they historically may have preferred
large conifers for drumming and foraging, they also forage in standing and fallen dead deciduous trees
of many sizes. Pileated woodpeckers create distinctive, rectangular foraging holes, which can normally
be identified as pileated woodpecker sign. These holes are surprisingly uncommon in dead and dying
trees and stumps on the subject property. One individual was observed on November flying between
and foraging on a large conifer on the forested slope and one of the cut snags in the landslide area.
5.3.5 Fish
As described in Section 4, WDFW SalmonScape data indicate the occurrence of rearing Coho salmon in a
tributary to Lunds Gulch Creek, approximately 1,000 feet north of the subject property (WDFW 2015).
As Coho are an anadromous species, it can be assumed that they also occur in the mainstem creek
downstream of this tributary. No streams or other fish habitat are present on the subject property.
G PROJECT DESCRIPTION
Site plans may be provided by the site developer. In summary, three single-family residences and
associated access driveways are planned. Regulatory steep slope areas along the western property
boundary and a 25 -foot top -of -slope buffer will remain undeveloped. Mitigation for habitat impacts is
described in Section 8 of this report.
Some view corridor cutting is proposed for the steep slope area adjacent to three of the proposed
single-family lots. Deciduous trees on the slope will be cut at approximately the level of the top of the
slope. Given the steepness of the slope and the location of most deciduous vegetation downslope from
the subject property, deciduous trees will be topped at approximately 5 to 20 feet. Trees will be topped
in a manner that encourages growth of branches, providing a dense midstory of vegetation up to 40 feet
from the ground, including branching. Topped trees will be maintained to limit heights to 40 feet or less
in future years. No coniferous trees will be cut or pruned except to remove dead wood, or as directed
by an ISA Certified Arborist.
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T VEGETATION MANAGEMENT IMPACTS
Plans for development of new homes are complete and not the focus of this report. Rather, this section
addresses the potential impacts of view corridor work and mitigation activities proposed on the steep
slope and in its adjacent buffer.
7.1 Direct Impacts
Topping deciduous trees as described in the previous section will encourage branching and leafy growth
from about 5 to 40 feet above ground level. This is meant to create a dense layer of vegetation to
provide habitat for mid -story species. Some loss of canopy deciduous habitat will occur, but the majority
of canopy cover is composed of conifers and will not be impacted. The overall effect of the action will be
to lower the sub -canopy vegetative layer by approximately 20 to 60 feet. Native understory vegetation
will not be removed, but the temporary increase in sunlight that will occur after trees are topped may
promote growth of groundcover. The impact to wildlife species is expected to be temporary, the result
of a temporary reduction in midstory and canopy habitat. A slight shift in wildlife species use could
potentially occur with the lowering of the sub-canopy/midstory that will result from tree topping. In
actuality, however, midstory wildlife communities are unlikely to respond noticeably to this small
alteration in habitat structure.
Construction noise and physical disturbance may occur during tree topping and will be temporary. The
primary construction impact will likely be avoidance of the area by wildlife.
7.2 Indirect and Cumulative Impacts
Indirect and cumulative impacts can be addressed insofar as land use of the surrounding landscape can
be expected to change over time. Most surrounding properties are already in single-family
development. Continued habitat fragmentation in the greater landscape is an ongoing concern, as
properties in the vicinity may be developed for denser residential use than presently exists. However,
habitat in the nearby Meadowdale Beach Park is unlikely to be degraded in the foreseeable future. As
well, regulatory buffers that apply to Lunds Gulch Creek and the Puget Sound shoreline are mandated to
retain their present functional value in perpetuity.
H MITIGATION
8.1 Mitigation Sequencing
The following avoidance and restoration activities are designed to minimize negative impacts to habitat
and enhance opportunities for wildlife to use the steep slope area of the subject property.
0 Work will be conducted under the supervision of an ISA certified arborist.
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• No conifers will be removed, damaged, or pruned in the steep slope area except as
determined by an ISA certified arborist.
• No removal of native understory vegetation is proposed.
• Topped deciduous vegetation will remain at a height conducive to vigorous regrowth and
branching.
• Care will be taken to avoid damage to lower branches and root zones of trees during work.
• Ground (non -target) vegetation will be avoided to the greatest extent practicable during
work.
• To reduce the risk of disturbance to non -target vegetation, heavy machinery such as track
hoes will not be used during vegetation management and mitigation work.
• Existing snags and some downed wood (to the extent that it does not constitute a hazard on
the steep slope) will be preserved on the site.
8.2 (litigation Plan
A detailed Mitigation Plan is included with this report. The plan consists of enhancing the top -of -slope
buffer with infill planting to bring the native plant density to 4 feet on -center (OC). Invasive vegetation,
including Himalayan blackberry, ivy, English laurel, and holly, will be removed (including roots) and
removal areas planted with native shrubs to 4 feet OC. Work will be conducted with hand tools only to
avoid disturbance of existing native vegetation.
The mitigation is intended to increase habitat value in the top -of -slope buffer and on the slope itself by
removing invasive vegetation, which tends to proliferate in monospecific infestations, and increase
vegetative cover, plant species diversity, and habitat structural diversity in the low and middle strata.
Enhancement areas total 9,847 square feet, plus some additional area where large holly and ivy trees
are to be removed. Mitigation areas will undergo maintenance at least twice yearly and be subject to
yearly milestones to monitor performance.
The included Mitigation Plan includes installation specifications, plant quantities, invasive removal
locations, and planting locations.
8.2.1 Goals and Objectives
1. Remove English ivy from trees and ground in buffer and slopes areas (refer to Sheet 1 for
locations). Plant removal areas with native shrubs where needed to bring shrub density to 4
feet OC. Depose of invasive plants offsite.
Remove Himalayan blackberry plants and sprouts, including roots, from buffer and slope
areas (refer to Sheet 1 for locations). Replace with native shrubs where needed to bring
density to 4 feet OC.
3. Remove invasive holly and laurel from locations indicated on Mitigation Plan Sheet 1.
Replace with native shrubs to bring density to 4 feet OC.
4. Maintain all planted areas free of invasive species for three years.
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5. Maintain all existing native plants in buffers and other removal/planting areas.
8.2.2 Installation
1. Site preparation, invasive plant removal, and planting will be conducted by experienced
landscapers under the guidance of a qualified professional (mitigation specialist, habitat
biologist, landscape architect, or arborist with mitigation experience).
2. Refer to Detail 1 on this sheet for installation specifications.
8.2.3 Maintenance
1. Maintenance will take place twice yearly, in spring and fall, for at least three years following
installation.
2. Installed plants will be watered by hand as necessary for 2 years following installation, or
until plants are established.
3. Dead mitigation plants will be replaced as needed during fall visits.
4. All invasive woody plants in the planting areas will be removed during maintenance,
including roots.
5. Non-native weeds will be removed in an 18 -inch diameter of installed plants.
6. Mulch rings will be replenished around installed plants to maintain a thickness of 4 inches
and diameter of 18 inches.
8.2.4 Performance standards
The mitigation will be measured against the following performance standards.
1. Survival:
a. 90% of installed plants will be alive by the end of Year 1. Plants will be replaced as
needed to achieve this standard.
b. At least 80% survival of installed plants will be achieved in Years 2 and 3.
2. Native woody vegetation cover:
a. 50% cover of native trees and shrubs will be achieved by Year 1 within planted slope and
buffer areas. Volunteer plants may count towards this cover standard.
b. 80% cover of native trees and shrubs will be achieved by the end of Year 3 within
planted slope and buffer areas. Volunteer plants may count towards this cover
standard.
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3. Native plant diversity: At least five native shrub species will be established in slope and buffer
areas by the end of Year 3. Volunteer plants may count towards this standard.
4. Invasive cover: No more than 10% cover by invasive plants will be present in any monitoring
year.
8.2.5 Monitoring Methods
An as -built plan will be completed after plant installation. The plan will depict quantities and locations of
plants by species. Monitoring will be conducted yearly after fall maintenance. A monitoring report will
be prepared after each monitoring visit. The report will include:
1. Counts of dead (installed) plants;
2. percent survival of installed plants;
3. percent cover estimates for each planted area, obtained using a standard cover estimation
method such as plot or transects; species count of installed plants;
4. a visual assessment of plant health;
5. a visual estimate of invasive plant cover;
6. site photos taken at established photo points;
7. notes on site disturbance, litter, vandalism, or other actions that may impair habitat
function; and
8. recommendations for maintenance and/or replanting as necessary to achieve performance
standards.
8.2.6 General Work Sequence
1. Remove invasive plants in all indicated areas and dispose material off-site.
2. Install plants per typical container planting detail as shown on this sheet (Detail 1) of the
mitigation plan.
3. Amend each planting pit with one shovel -full of organic compost.
4. Water each plant thoroughly by hand/hose to remove air pockets.
5. Install a 4 -inch -thick layer of coarse wood chip mulch around the base of each installed plant in
an 18 -inch -diameter circle. Mulch should not touch plant stems.
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April 4, 2016
Avia Environmental
8.2.7 Contingency Plan
If performance standards are not met by the end of the monitoring period, a qualified professional will
evaluate the site for causes of failure and make recommendations for remediation. Monitoring will
continue until performance standards are met.
8.2.8 Planting Notes
1. The mitigation area will be preserved for the life of the project.
2. A supervising qualified professional will supervise plant placement.
3. The qualified professional may make minor species substitutions in the field. Any changes
will be reflected in the as -built plan.
4. Plant materials will be inspected by the supervising qualified professional on delivery.
Unhealthy plants will be rejected.
5. Actions and activities will be conducted in accordance with the details of the Mitigation
Plan.
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April 4, 2016
REFERENCES
Avia Environmental
Donnelly, R. and J.M. Marzluff. 2004. Importance of reserve size and landscape context to
urban bird conservation. Conserv. Biol. 18:733-745.
Johnson, D.H. and T.A. O'Neil. Wildlife -Habitat Relations in Oregon and Washington. Oregon
State University Press. Corvallis, OR.
Lewis, J.C. and J.M. Azerrad. 2003. Pileated woodpecker. Pages 29-1 — 29-9 in E. Larsen, J.M.
Azerrad, and N. Nordstrom, editors. Management Recommendations for Washington's
Priority Species. Vol. IV: Birds. Washington Department of Fish and Wildlife, Olympia,
WA.
Seattle Audubon Society. 2015. Birdweb website (www birdweb.or ).
Washington Department of Fish and Wildlife (WDFW). 2015. Priority Habitats and Species
Program online database, accessed November 2015.
. 2015. SalmonScape online database, accessed November 2015.
14
Appendix A - Site Photographs
Photo 1. Undergrowth and branching removed from development area
Photo 2. Previously cleared slope
Photo 3. Forested steep slope
Photo 4. Bald eagles in conifer near Puget Sound shoreline
Appendix B - SalmonScape Map
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Appendix C - PHS Map