HomeMy WebLinkAboutAttachment 4a - D1 Biological Impact Analysis Report PART 2
HABITAT RESTORATION AND SENSITIVE PLANT SPECIES MITIGATION PLAN
FOR THE SUNBOW II PHASE 3 SPA PLAN AMENDMENT
CHULA VISTA, CA
Prepared for:
Lennar‐ San Diego Division
16465 Via Esprillo, Suite 150
San Diego, CA 92127
Contact: David Shepherd
Phone: 858‐618‐4942
E‐mail: David.Shepherd@lennar.com
Prepared by:
Merkel & Associates, Inc.
Attn: Kyle Ince
5434 Ruffin Road
San Diego, CA 92123
Phone: (858) 560‐5465
Fax: (858) 560‐7779
Revised: February 2021
December 2020
Kyle Ince, Senior Biologist
Keith Merkel, Principal Consultant
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 i
TABLE OF CONTENTS
INTRODUCTION.............................................................................................................................................1
Location.....................................................................................................................................................2
General Physiography ...............................................................................................................................2
Site Selection.............................................................................................................................................5
Rationale for Selected Site.....................................................................................................................5
Site Conditions.......................................................................................................................................5
IMPLEMENTATION PLAN ..............................................................................................................................8
Site Preparation Methods.........................................................................................................................8
Weed and Debris Removal ....................................................................................................................8
Seed Salvage..........................................................................................................................................8
Bentonitic Claystone Salvage.................................................................................................................8
Topsoil Salvage ......................................................................................................................................9
Topsoil Application and Decompaction.................................................................................................9
Propagule Introduction Methods............................................................................................................10
Native Grassland..................................................................................................................................10
Container Plants...............................................................................................................................10
Hydroseeding...................................................................................................................................10
Diegan Coastal Sage Scrub...................................................................................................................11
Container Plants...............................................................................................................................11
Hydroseeding...................................................................................................................................12
Erosion Control........................................................................................................................................13
Fencing/Signage......................................................................................................................................13
Installation Letter....................................................................................................................................13
Implementation Schedule.......................................................................................................................13
Plant Establishment.................................................................................................................................14
Natural Precipitation/Irrigation...........................................................................................................14
Weeding...............................................................................................................................................14
GENERAL IMPLEMENTATION SPECIFICATION.............................................................................................15
Responsibilities and Qualifications..........................................................................................................15
Owner/Applicant .................................................................................................................................15
Revegetation Team..............................................................................................................................15
Revegetation Contractor..................................................................................................................15
Project Biologist...............................................................................................................................15
MAINTENANCE PROGRAM..........................................................................................................................16
Weed Control..........................................................................................................................................16
Supplemental Watering ..........................................................................................................................16
Trash and Debris......................................................................................................................................16
MONITORING AND SUCCESS ASSESSMENT................................................................................................17
Monitoring and Reporting.......................................................................................................................17
Reference Site Monitoring...................................................................................................................17
Qualitative Monitoring........................................................................................................................17
Quantitative Monitoring......................................................................................................................18
Otay Tarplant ...................................................................................................................................18
Orcutt’s Bird’s‐beak .........................................................................................................................19
Decumbent Goldenbush and San Diego County Viguiera................................................................19
Photographic Documentation .............................................................................................................19
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 i
Monitoring Schedule ...........................................................................................................................20
Success Criteria........................................................................................................................................20
Otay Tarplant ...................................................................................................................................20
Habitat Area Goal.............................................................................................................................20
Habitat Coverage Goal.....................................................................................................................20
Project Mitigation Standards...............................................................................................................21
Orcutt’s Bird’s‐beak .........................................................................................................................21
Decumbent Goldenbush and San Diego County Viguiera................................................................21
Annual Project Progress Reports.........................................................................................................21
Remedial and Contingency Measures.................................................................................................22
Long‐term Management......................................................................................................................22
LITERATURE CITED/REFERENCES ................................................................................................................23
LIST OF FIGURES
Figure 1. Vicinity Map...................................................................................................................................3
Figure 2. Biological Resources......................................................................................................................4
Figure 3. Habitat Restoration and Otay Tarplant Impact/Topsoil Salvage Areas.........................................6
Figure 4. Habitat and Sensitive Species Restoration Areas ..........................................................................7
LIST OF TABLES
Table 1. Native Grassland Restoration Container Plant Palette (1.71 acres) ............................................10
Table 2. Native Grassland Restoration Seed Mix (1.71 acres)...................................................................10
Table 3. Diegan Coastal Sage Scrub Container Plant Palette (3.13 acres).................................................12
Table 4. Diegan Coastal Sage Scrub Seed Mix (3.13 acres)........................................................................12
Table 5. Implementation Schedule............................................................................................................14
Table 6. Performance Goals for Vegetative Cover.....................................................................................21
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 1
INTRODUCTION
Merkel & Associates (M&A) was contracted by Lennar Homes (Project Applicant) to prepare a
habitat restoration and compensatory sensitive plant species mitigation plan for impacts associated
with the Sunbow II Phase 3 Amendment Project (Project) that includes a proposed Multiple Species
Conservation Plan (MSCP) Preserve Boundary Line Adjustment (BLA). The Project proposes to
mitigate for impacts to Otay tarplant (Deinandra conjugens), Orcutt’s bird’s‐beak (Dicranostegia
orcuttiana), decumbent goldenbush (Isocoma menziesii var. decumbens), and San Diego County
viguiera (Bahiopsis laciniata) through the following:
1) Conveyance of the proposed Sunbow MSCP Preserve lands to the Chula Vista Central City
Preserve lands be conserved, maintained, and managed by the City of Chula Vista in
perpetuity as directed in the Chula Vista Central City Preserve Area‐Specific Management
Directives for Preserve Management Area 3 (RECON Environmental, April 26, 2004) and
funded by the Sunbow Preserve Community Facilities District (No. 98‐3); and
2) Implementation of this project restoration plan.
This plan has been prepared by a qualified City‐approved biologist familiar with the City’s MSCP
Subarea Plan and includes but is not limited to: an implementation plan; appropriate seed mixtures
and planting methods; an irrigation method; quantitative and qualitative success criteria; a
maintenance, monitoring, and reporting program; an estimated completion time; and contingency
measures. The project applicant is required to prepare and implement this plan subject to the
oversight and approval of the Development Services Director (or their designee). The objectives of
this habitat restoration and sensitive plant species mitigation plan are to:
Restore non‐native grassland to native grassland and Diegan coastal sage scrub habitats that
will support sensitive plant species within areas of proposed MSCP BLA Give areas;
Compensate for the proposed project impacts to Orcutt’s bird’s‐beak, decumbent
goldenbush, and San Diego County viguiera within the proposed habitat restoration areas
through the implementation of mitigation standards for these species; and
Enhance native grassland restoration areas with Otay tarplant.
Biological surveys including focused rare plant surveys of the Project area (Figure 1) were
conducted by M&A during the winter of 2019, spring/summer of 2020, and winter (January) of 2021
(1.66‐acre off‐site area on Otay Ranch property, only) (Merkel & Associates 2021). The distribution
of vegetation communities and locations of sensitive plant populations within the project boundary
are shown on Figure 2. Four of the sensitive plant species (i.e., Otay tarplant, Orcutt’s birds’‐beak,
decumbent goldenbush, San Diego County viguiera) would be significantly impacted through
implementation of the project. Detail regarding the sensitivity status, on‐site distribution, and
habitat of these species is provided within the biological impact analysis report for the Sunbow II
Phase 3 project (Merkel & Associates 2021).
Three of the sensitive species for which impacts have been found to be significant will require
compensatory mitigation in the form of habitat restoration and plant replacement in the restored
habitat. A total of 91 Orcutt’s bird’s beak, 289 decumbent goldenbush, and 5,952 San Diego County
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 2
viguiera, will be impacted by the Project and an equivalent number of each must be replaced within
the onsite restoration area.
A total of 5,449 Otay tarplant individuals were mapped within the Sunbow II Phase 3 property. A
total of 4,044 individuals were mapped within the existing preserve and 1,405 were mapped
outside the existing preserve (Merkel & Associates 2021). Total quantity and population extent
mapped for the site is based on the greatest number of plants and extent recorded from the winter
surveys (which included mostly vestigial remains of plants) and the early summer surveys (which
included flowering plants). It should be noted that population size of this annual plant is expected
to fluctuate yearly and is dependent upon climatic factors such as temperature and rainfall.
Under the project, a total of 836 Otay tarplant individuals distributed over 0.34 acre are anticipated
to be impacted. The project proposes to mitigate Otay tarplant impacts through conveyance of
Preserve lands to the City that include substantially more than 836 Otay tarplant individuals and
significantly more than 0.34 acres of occupied habitat. As a result, mitigation needs for this species
would be met by conveyance alone.
Because the mitigation requirements for Otay tarplant are met through conservation of existing
plant populations the restoration of this species under this plan is non‐compensatory in nature.
Therefore, the restoration goals for Otay tarplant under this restoration plan are to enhance the
distribution and abundance of this narrow endemic species within the habitat restoration without
establishment of the same compensatory mitigation standards as would apply to the other species
included in this plan.
The focus of this plan is to identify the implementation, monitoring requirements, and performance
standards for required compensatory mitigation as well as restoration goals that shall be used in
evaluating the restoration effort. The mitigation standards and restoration goals provided within
this report will follow federal, state, and local rules, guidelines, and regulations, including the
California Environmental Quality Act (CEQA) and the Chula Vista Multiple Species Conservation Plan
(MSCP) Subarea Plan (City of Chula Vista 2003).
LOCATION
The Sunbow II Phase 3 property (Assessor’s Parcel Numbers 644‐011‐06‐00 and 644‐020‐11‐00) is
located south of Olympic Parkway (previously East Orange Avenue) and east of Brandywine in the
City of Chula Vista within San Diego County. Further, the project site is situated within Sections 17
and 18, Township 18 South, Range 1 West of the U.S. Geological Survey 7.5 minute Imperial Beach,
California Quadrangle (Figure 1). The restoration area will occur near the northeast corner of the
Sunbow II Phase 3 property (Figures 3 and 4).
GENERAL PHYSIOGRAPHY
The elevation of the Project area ranges from approximately 212 feet mean sea level (MSL) at the
Poggi Creek channel storm drain outlet near the northwest corner of the site to a high elevation of
470 MSL located near the southeast corner of the site. The soils within the project study area are
derived from Alluvium, Otay Formation, San Diego Formation, Sweetwater Formation and
previously placed fill (Geocon 2019; Geologic Map). Soils are mapped as Diablo clay, 15 to 30
µ
Merkel & Associates, Inc.
M&A #94-021-36
Project Vicinity MapSunbow II Phase 3 SPA Amendment Figure 1
Source: USGS 7.5' Imperial Beach, CA Quadrangle1:24000
Project Site
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Merkel & Associates, Inc.
Sunbow II Phase 3 SPA AmendmentBiological Resources Map Figure 2
Aerial Source: Merkel & Associates Jan. 2020 Created on: January 19, 2021
0 300 600150Feet
OLYMPIC PKWY
M&A #94-021-36
Special Status Species (Numbers Provided IndicateTotal Observed On-site for Each Species)
Special Status Flora
!(Otay Tarplant (Deinandra conjugens)- 5,449
!(Decumbent Goldenbush (Isocoma menziessii var. decumbens)- 803
!(Orcutt's Bird's-beak (Dicranostegia orcuttianus)- 911
!(Ashy Spike-moss (Selaginella cinerascens)- 2
!(Coast Barrel Cactus (Ferocactus viridescens)- 2
!(Palmer's Sagwort (Artemisia palmeri)- 44
!(San Diego County Needlegrass (Stipa diegoense)- 10
!(
!(San Diego Bursage (Ambrosia chenopodifolia)- 24
!(San Diego Marsh Elder (Iva hayesiana)- 816
!(Small-flowered Bindweed (Convolvulus simulans)- 91
!(Southwestern Spiny Rush (Juncus acutus ssp. leopoldii)- 750
San Diego County Viguiera (Bahiopsis laciniata)- 7,647
Special Status Fauna
Flyover Only
#0 Coastal California Gnatcatcher (Polioptila californica californica)- 2
#0 Least Bell's Vireo (Vireo belli pusillus)- 1
#0 Nuttall's Woodpecker (Picoides nuttallii)- 1
#0 Yellow Breasted Chat (Icteria virens)- 3
#0 Yellow Warbler (Dendroica petechia)- 5
#0 Orange-throated Whiptail (Aspidoscelis hyperythra)- 1
#0 Two-striped Garter Snake (Thamnophis hammondii)- 1
Cooper's Hawk (Accipiter cooperii)
White-tailed Kite (Elanus leucurus)
Northern Harrier (Circus cyaneus),
,
,
,
,
Vegetation Communities
Coastal and Valley Freshwater Marsh
Southern Willow Scrub
Mule Fat Scrub
Diegan Coastal Sage Scrub
Native Grassland
Non-native Grassland
Non-native Vegetation
Urban/Developed
Waters of the State (RWQCB)/Streambed (CDFW)
Other
MSCP City of Chula Vista 100% Preserve
Offsite Mapping Buffer
Project Site
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 5
percent slopes; Diablo clay, 30 to 50 percent slopes; Linne clay loam, 9 to 30 percent slopes;
Olivenhain cobbly loam, 9 to 30 percent slopes; Salinas clay loam, 2 to 9 percent slopes; Olivenhain
cobbly loam, 2 to 9 percent slopes on the mesa top; and terrace escarpments on the surrounding
slopes (USDA 2002) (Figure 3). The regional climate is characterized by warm, dry summers and
mild winters with most of the annual precipitation falling between December and March. Annual
rainfall is approximately 9‐13 inches (USDA‐NRCS 2002).
Areas supporting Otay tarplant include mostly gentle, north‐facing slopes with soils predominately
mapped as Diablo Clay with a relatively small area of Linne Clay Loam near the southwest corner of
the property. The area proposed for restoration occurs on a gentle north‐facing slope with soils
mapped as Diablo Clay (Figure 3).
SITE SELECTION
Rationale for Selected Site
The restoration area has been discussed with the City of Chula Vista and the Resource Agencies.
The location provides an opportunity to enhance habitat within the City preserve system and
augment upland habitat along Poggi Canyon Creek. The restoration will occur within the proposed
MSCP BLA designated area to be put into the preserve system “give” areas. The area occurs on a
gentle north‐facing slope on Diablo Clay soils which is similar to conditions of where a majority of
the Otay tarplant populations are found to occur on‐site within the existing preserve to the west of
the enhancement areas within intact native grasslands. No Otay tarplant was observed in the
proposed restoration area during focused surveys; however, populations of Otay tarplant and
Orcutt’s bird’s‐beak are found adjacent along with both Diegan Sage Scrub and native grasslands.
As such, the selected site is expected to provide habitat contiguity and be similar in capacity to
support targeted restoration. In addition, the proximity of the site to existing desirable habitat
conditions and natural populations of targeted species in the restoration program increases the
chances for success.
Site Conditions
The restoration area is currently dominated by non‐native grassland comprised of invasive grass
and forb species including purple false brome (Brachypodium distachyon), Italian rye grass (Festuca
perennis), wild oat (Avena spp.), black mustard (Brassica nigra), and sweet fennel (Foeniculum
vulgare). These plants, especially the grass species, form a dense thatch that precludes the
germination and growth of Otay tarplant and other clay associates which have difficulty competing
with the Eurasian grasses and weeds.
Diablo clay, 30 to 50 percent slopes Linne clay loam,9 to 30 percent slopes
Diablo clay, 15 to 30 percent slopes
Salinas clay loam, 2 to 9 percent slopes
Linne clay loam,9 to 30 percent slopes Olivenhain cobbly loam, 9 to 30 percent slopes
2'
0.5
'
3'0.5'1
2
'
2'1'6'3'1'
/
3
'
6'3'µ
M&A #94-021-36
Merkel & Associates, Inc.
Sunbow II Phase 3 SPA AmendmentHabitat Restoration and Otay Tarplant Impact/Topsoil Salvage Areas Figure 3
Created on: January 19, 2021
0 300 600150Feet
OLYMPIC P
K
W
Y
Vegetation Communities
Coastal and Valley Freshwater Marsh
Southern Willow Scrub
Mule Fat Scrub
Diegan Coastal Sage Scrub
Native Grassland
Non-native Grassland
Non-native Vegetation
Urban/Developed
Waters of the State (RWQCB)/Streambed (CDFW)
Special Status Species (Numbers Provided IndicateTotal Observed On-site for Each Species)
Special Status Flora
!(Otay Tarplant (Deinandra conjugens) - 5,449
!(Decumbent Goldenbush (Isocoma menziessii var. decumbens) - 803
!(Orcutt's Bird's-beak (Dicranostegia orcuttianus) - 911
!(Ashy Spike-moss (Selaginella cinerascens) - 2
!(Coast Barrel Cactus (Ferocactus viridescens) - 2
!(Palmer's Sagwort (Artemisia palmeri) - 44
!(San Diego County Needlegrass (Stipa diegoense) - 10
!(San Diego County Viguiera (Bahiopsis laciniata) - 7,647
!(San Diego Bursage (Ambrosia chenopodifolia) - 24
!(San Diego Marsh Elder (Iva hayesiana) - 816
!(Small-flowered Bindweed (Convolvulus simulans) - 91
!(Southwestern Spiny Rush (Juncus acutus ssp. leopoldii) - 750
,
,
,
,
,
Other
MSCP Minor Amendment Area
MSCP County of San Diego Take Authorized Area
MSCP Proposed Preserve Habitat Restoration
Project Site
MSCP City of Chula Vista 100% Preserve
MSCP Proposed Preserve (Hunsaker September 2020)
Soils
Otay Tarplant Reference Site
Otay Tarplant Impact/Topsoil Salvage Area
Proposed MSCP Take Area (Hunsaker June 2020)
Offsite Mapping Buffer
Aerial Source: Merkel & Associates Jan. 2020
µ
M&A #94-021-36
Merkel & Associates, Inc.
Sunbow II Phase 3 SPA AmendmentHabitat and Sensitive Species Restoration Areas Figure 4
Created on: January 19, 2021
OLYMPIC P
K
W
Y
Vegetation Communities
Coastal and Valley Freshwater Marsh
Southern Willow Scrub
Mule Fat Scrub
Diegan Coastal Sage Scrub
Native Grassland
Non-native Grassland
Non-native Vegetation
Urban/Developed
Restoration Areas
Otay Tarplant/Native Grassland (0.57 acre)
Diegan Coastal Sage Scrub (2.06 acres)
Native Grassland (2.13 acres)
MSCP Proposed Preserve Habitat Restoration
Other
MSCP City of Chula Vista 100% Preserve
0 100 20050Feet LOCATOR INSET VIEW
Aerial Source: Merkel & Associates Jan. 2020
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 8
IMPLEMENTATION PLAN
SITE PREPARATION METHODS
Weed and Debris Removal
All soil surfaces within proposed restoration areas shall be free of debris and weed growth prior to
top‐soil application and planting. Most of the vegetation occurring in these areas is comprised of
non‐native annual forbs and grasses including black mustard (Brassica nigra), purple false brome
(Brachypodium distachyon), and slender wild oat (Avena barbata). The 4‐6 inches of soil will be
scrapped with heavy machinery to remove the thatch and underlying non‐native seed bank.
After clearing, the site may be treated with an herbicide to treat any remaining aggressive non‐
native perennial species such as sweet fennel (Foeniculum vulgare) and tree tobacco (Nicotiana
glauca) that are not fully removed by the surface scraping. This would be done to prevent their re‐
emergence. All debris deemed unsuitable to remain on‐site by the Project Biologist shall be
removed and disposed of properly at a certified landfill. Debris may include introduced trash, rock,
non‐native tree leaf litter (e.g., eucalyptus trees) or any construction refuse associated with building
activities that may conflict with the restoration effectiveness.
Seed Salvage
Seed from Otay tarplant will be collected from all proposed impact areas and sowed within
restoration areas during the appropriate planting season. The seed will be collected when it is
mature (i.e., summer) by hand and placed in breathable containers (i.e., burlap bags) and
transferred to a native plant nursery for cleaning and storage until ready for sowing during the
following planting season. Approximately 5 percent of the seed will be held at the nursery for
bulking purposes where it can be propagated for one season for the purpose of seed amplification
in the event that a seed source is needed for remedial planting or propagation. The bulked seed
will be cleaned and prepared for sowing within the restoration areas during the fall of the second
year. In the event the seed collected from impact sites is not productive, and seed propagated at
the nursery is insufficient, a special seed collection from natural populations of Otay tarplant within
the property’s open space may be arranged, as determined by the Project Biologist.
Bentonitic Claystone Salvage
Various areas of the Project site feature inclusions of bentonitic claystone soil (Geocon 2019).
Although this soil is not conducive for development given its expansive qualities, it is often
associated with rare, clay endemic plants including Otay tarplant as well as the federally listed
Threatened and state listed Endangered San Diego thorn‐mint (Acanthomintha ilicifolia) which has
historic occurrences on similar soils in the immediate area but which was extirpated in the Sunbow
area approximately three decades ago. The transfer of this soil to the restoration area will benefit
the growth of Otay tarplant as well as provide the opportunity for introduction of San Diego thorn‐
mint either through natural recruitment or sowing of seed from a yet to be determined approved
seed translocation opportunity. Introduction of San Diego thorn‐mint to the restoration area would
assist the project in supporting the Project’s one Conservation Recommendation stated in the
USFWS Biological Opinion for the Sunbow II, Phase 3 project as stated below.
• #1 The open space habitats proposed for Sunbow site are considered to be important
for numerous species which are candidates or future candidates for federal listing. Many of
Habitat Restoration and Mitigation Plan Sunbow II Phase 3 Amendment
Merkel & Associates #94‐021‐33 9
these species currently carry state listing status and are a focus of multi‐species planning
efforts intended to reduce the need for future listings. Among the most important resources
within the open space are coastal cactus wrens and Otay tarplant. Potential exists for the
compatible enhancement of these resources along with the restoration of on‐site sage scrub
habitats. In addition, there is a good potential for restoration of San Diego thornmint to
some of the open space clay lenses. The Service would look favorably on such multi‐species
enhancement efforts should the Corps or applicant incorporate consideration of these
species into the on‐site restoration and maintenance program.
While Conservation Recommendations are not obligatory, the potential areas for acting on this
recommendation are very limited within the Chula Vista Subarea preserve system and the present
restoration is ideally suited to support expansion of heavy clay habitat and narrow endemic
management objectives.
A 6‐10 inch layer of the salvaged bentonitic claystone will be applied and keyed in to create the final
rough grade of the lower slopes of the restoration area. The soil transfer will occur prior to the
mass grading of the site and is expected to require the use of heavy equipment which may include
scrappers, dozers, loaders, and hauling trucks. A total of 850 cubic yards of bentonite clay are
expected to be salvaged and transferred to the restoration area and placed in areas where Otay
tarplant restoration is to be conducted (Figure 4). This claystone will be moderately compacted and
then capped with a thin veneer of salvaged topsoil (approximately 2‐4 inches) containing Otay
tarplant seed as described below.
Topsoil Salvage
In areas where Otay tarplant will be impacted by the development project, the top 2 to 4 inches of
topsoil will be salvaged prior to mass grading in these areas. The topsoil is expected to contain the
seed of Otay tarplant as well as beneficial microbes, invertebrates, and mycorrhizal fungi. At the
discretion of the Project Biologist, the native vegetation in these areas will be crushed and then
mixed into the topsoil prior to salvage. Topsoil salvage is expected to occur prior to or during mass
grading of the project. The salvage and application is expected to utilize similar equipment as
described above for the bentonitic claystone translocation described above. In soil salvage areas
that are excessively weedy as identified by the Project Biologist, all non‐native biomass will be
removed from the surface prior to salvaging the soil. This work will be conducted by hand using
weed trimmers, rakes, and blowers. Whenever possible, the biomass removal will be conducted
prior to non‐native plant species setting seed.
Topsoil Application and Decompaction
All topsoil containing seed from Otay tarplant will be applied to the receptor locations following the
application of the bentonitic claystone described above. The topsoil will be applied to match the
contours of the surrounding grade. The soil shall be spread to a depth of 2 to 4 inches and then
track walked to provide minimal compaction. Soils overly compacted will be gently ripped using a
skip loader with an attached gannon box with rippers or by other comparable methods (e.g., plow
or ripping fork drawn by tractor) that are approved by the Project Biologist.
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PROPAGULE INTRODUCTION METHODS
Native Grassland
Container Plants
Following site preparation container plants, including decumbent goldenbush, will be planted
within the native grassland restoration area. The plant materials, container size, and unit count to
be used in this restoration are shown in Table 1. The plant material distribution on the site is to be
spotted by the Project Biologist and will be unevenly distributed to develop natural aggregations
and clustering of species following naturally occurring habitat patterns.
Table 1. Native Grassland Restoration Container Plant Palette (1.71 acres)
Botanical Name Common Name Unit Size Density
(centers)
Percent
Cover
Approximate
Count
Corethrogyne
filaginifolia Sand Aster 1‐gallon 3‐foot 5.0 413
Isocoma menziesii
var. decumbens Decumbent Goldenbush 1‐gallon 3‐foot 2.0 165
Stipa diegoensis San Diego Needlegrass 1‐gallon 5‐foot 20.0 596
Stipa pulchra Purple Needlegrass 1‐gallon 4‐foot 50.0 2,327
Total 3,501
Hydroseeding
Following planting, the native grassland will be hydroseeded. The hydroseed mix, including
decumbent goldenbush, is provided in Table 2).
Table 2. Native Grassland Restoration Seed Mix (1.71 acres)
Botanical Name Common Name
Minimum
Purity/
Germination
Pure Live
Seed
Percentage
Lbs./Acre Total Lbs.
Bloomeria crocea Common
Golden Star 95/80 76.0 0.5 0.86
Convolvulus simulans Small‐flowered
bindweed NA NA 0.5 0.86
Corethrogyne
filaginifolia Sand Aster 5/40 2.0 4.0 6.84
Dichelostemma
capitatum ssp.
capitatum
Blue Dicks 95/80 76.0 0.5
0.86
Eriophyllum
confertiflorum Golden Yarrow 30/50 15.0 2.0 3.42
Eschscholzia californica California Poppy 98/75 73.5 2.0 3.42
Grindelia camporum Rayless
Gumplant 30/65 19.5 2.0 3.42
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Isocoma menziesii var.
decumbens
Decumbent
Goldenbush 25/40 10.0 2.0 3.42
Lasthenia coronaria Royal Goldfields 50/60 30.0 1.0 1.76
Lupinus bicolor Miniature
Lupine 98/85 83.3 2.0 3.42
Melica imperfecta Coast Range
Melic 90/60 54.0 1.0 1.76
Sisyrinchium bellum Blue‐eyed Grass 95/75 71.3 2.0 3.42
Stipa diegoensis San Diego
Needlegrass 70/60 42.0 1.0 1.76
Stipa pulchra Purple
Needlegrass 70/60 42.0 8.0 14.08
Total 28.50 49.30
A slurry comprised of 2,000 lbs./acre of fiber mulch and 160 lbs./acre of soil stabilizer (e.g., Super
Tack) will be applied with the proposed seed mix. All seeding shall occur in the late fall or early
winter months (i.e., November 1 through December 15) to take advantage of seasonal conditions.
All seeding will occur following plant installation.
The above seed mix and container plant list were selected based upon existing species composition
of native grassland habitat found on‐site. Additional species known from the local region have also
been included in the above mix to increase species diversity. All container plants/seed will be
propagated/collected from plants within a five‐mile radius of the work area to the extent
practicable. It is preferred, when feasible, that seed be collected from on‐site proposed
development areas (prior to construction) as well as open space areas of the property. This is
especially relevant for sensitive species with a limited local distribution including small‐flowered
bindweed (Convolvulus simulans) and San Diego County needlegrass (Stipa diegoensis). All
seed/plants are expected to be contract collected/grown, and therefore sufficient lead time (e.g., 6‐
months) is required for obtaining the required materials. Seed used for dispersal and growing of
container plants will be required to be collected when it becomes available during the late spring‐
early summer
The Otay tarplant collected from the site will be broadcast under the supervision of the Project
Biologist into the smaller Otay tarplant restoration areas prior to application of the grassland
hydroseed mix.
Diegan Coastal Sage Scrub
Container Plants
Following site preparation, the Diegan coastal sage scrub areas will be planted with the container
plants, including decument goldenbush and San Diego County viguiera, identified in Table 3.
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Table 3. Diegan Coastal Sage Scrub Container Plant Palette (3.13 acres)
Botanical Name Common Name Unit
Size
Density
(center)
Percent
Cover
Approximate
Count
Artemisia californica Coastal Sagebrush 1‐gallon 4‐foot 25.0 2,130
Bahiopsis laciniata San Diego Viguiera 1‐gallon 4‐foot 37.0 3,152
Bergerocactus emoryi Velvet Cactus 1‐gallon 4‐foot 3.0 256
Cylindropuntia prolifera Coast Cholla 1‐gallon 4‐foot 2.0 170
Cylinropuntia californica
var. californica Snake Cholla 1‐gallon 4‐foot 2.0 170
Eriogonum fasciculatum
var. fasciculatum Flat‐top Buckwheat 1‐gallon 4‐foot 15.0 1,278
Isocoma menziesii var.
decumbens
Decumbent
Goldenbush 1‐gallon 4‐foot 4.0 341
Isomeris arborea Bladderpod 1‐gallon 4‐foot 2.0 170
Lycium brevipes var.
brevipes Common Desert Thorn 1‐gallon 6‐foot 3.0 114
Lycium californicum California Desert Thorn 1‐gallon 6‐foot 3.0 114
Opuntia littoralis Prickly Pear 1‐gallon 4‐foot 5.0 426
Rhus integrifolia Lemonadeberry 1‐gallon 10‐foot 5.0 68
Simmondsia chinensis Jojoba 1‐gallon 4‐foot 5.0 426
Yucca schidigera Mohave Yucca 1‐gallon 4‐foot 3.0 255
Total 9,070
Hydroseeding
The seed mix, including decument goldenbush and San Diego County viguiera, will be applied to the
Diegan coastal sage scrub areas is identified in Table 4.
Table 4. Diegan Coastal Sage Scrub Seed Mix (3.13 acres)
Botanical Name Common Name
Minimum
Purity/
Germination
Pure Live
Seed
Percentage
Lbs./Acre Total
Lbs.
Acmispon glaber var.
glaber Coastal Deerweed 95/80 76.0 3.0 9.39
Bahiopsis laciniata San Diego Viguiera 50/60 30.0 1.0 3.13
Dichelostemma
capitatum ssp.
capitatum
Blue Dicks 95/80 76.0 0.5 1.57
Eriophyllum
confertiflorum Golden Yarrow 30/50 15.0 2.0 6.26
Eschscholzia californica California Poppy 98/75 73.5 2.0 6.26
Isocoma menziesii var.
decumbens
Decumbent
Goldenbush 25/40 10.0 2.0 6.26
Lasthenia coronaria Royal Goldfields 50/60 30.0 1.0 3.13
Lupinus bicolor Miniature Lupine 98/85 83.3 2.0 6.26
Stipa lepida Foothill Needlegrass 70/60 42.0 8.0 25.04
Total 21.5 67.30
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In addition, Orcutt’s bird’s‐beak seed will be collected from the site and will also be included in the
seed mix. The above seed mix and container plant list were selected based upon existing species
composition of Diegan coastal sage scrub found on‐site. Additional species known from the local
region have also been included in the above mix to increase species diversity. All container
plants/seed will be propagated/collected from plants within a five‐mile radius of the work area to
the extent practicable. It is preferred, when feasible, that seed be collected from on‐site proposed
development areas (prior to construction) as well as open space areas of the property.
EROSION CONTROL
Standard erosion control BMP devices (i.e., straw wattles, silt fence) will be installed on finished
slopes of the restoration area having a gradient that is greater than 4:1 to ensure soil stabilization
and prevention of sediment transport. All devices will be properly trenched per standard
installation guidelines for these products and will stay in place until vegetation has sufficiently
established as determined by the Project Biologist. Erosions control BMP devices will be installed
following site preparation and prior to planting.
FENCING/SIGNAGE
The restoration area is located in a relatively remote area of the property without easy access from
the public. No fencing or signage is specified unless determined at a later date to be necessary due
to trespass/vandalism.
INSTALLATION LETTER
A letter summarizing the as‐built conditions of the site will be written by the Project Biologist
following completion of the installation. The letter will be used to assist with the long‐term
monitoring and maintenance of the site and will include:
a summary of the bentonitic claystone salvage and application;
a summary of the Otay tarplant seed translocation effort including quantities of seed
collected/cleaned, applied to the site, and retained for future use;
a summary of the Orcutt’s bird’s‐beak seed translocation effort including quantities of seed
collected/cleaned, and applied to the site;
a summary of species and quantities of each planted, including decumbent goldenbush and
San Diego viguiera;
a summary of the methods utilized to salvage and apply topsoil to the restoration site;
a figure depicting locations of bentonitic claystone salvage, topsoil salvage, and final
dimensions of the restoration site including native grassland and coastal sage scrub areas;
a description of any problems or unexpected issues related to the work;
identification of any variations from the described approach specified in this plan;
photographs depicting the installation including fixed photo points of the restoration site to
use as reference points for future reports.
IMPLEMENTATION SCHEDULE
Implementation of this plan shall occur concurrently with development of the Project. The specific
year during which implementation will occur has not yet been identified and is dependent upon
Project approvals and the development schedule. A proposed schedule based on biological
considerations including specific seasonal timing requirements is provided in Table 5.
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Table 5. Implementation Schedule
Task Timing of Implementation
Otay Tarplant Baseline Survey Completed Summer 2020
Field Delineation Summer During Blooming Period
Collect Otay Tarplant and Orcutt’s Bird’s‐beak
Seed from Impact Areas
Summer First Year
Salvage and Transfer of Otay Tarplant Topsoil Summer/Fall Following Seed Collection
Conduct Seed Bulking at Nursery Winter of First Year
Conduct Site Preparation Work Fall of First Year
Install Above Grade Irrigation System Fall of First Year
Install Seed and Container Plants Late Fall or Early Winter of First Year
Conduct Supplemental Seeding/Planting Fall or Early Winter of Second Year
PLANT ESTABLISHMENT
Natural Precipitation/Irrigation
Plant establishment will be mostly dependent upon natural precipitation. As such, the hydroseed
application will occur during the late fall or early winter months to take advantage of seasonal
conditions. If possible, the application will be timed to coincide with a rainstorm event that occurs
after the slurry mulch is allowed to dry (typically 24 hours). As a contingency measure if rainfall is
insufficient for seed germination and plant growth, a simple, above grade, overhead irrigation
system will be constructed to be used to supplement natural rainfall. Use of this system is expected
to occur as needed, on a monthly basis, under the direction of the Project Biologist. All above
ground irrigation system components will be removed upon receiving final signoff.
Weeding
Native plant establishment requires diligent weed control. Weed control is especially important
during the first two years when native plants are easily out‐competed for soil nutrients and sunlight
by quick growing non‐native forbs and grasses. Typical quick growing weeds in restoration areas
include Eurasian grasses such as ripgut (Bromus diandrus), red brome (Bromus madritensis ssp.
rubens), and wild oat (Avena barbata). Common invasive forbs include black mustard (Brassica
nigra), sweet fennel (Foeniculum vulgare), California burclover (Medicago polymorpha), and white
sweetclover (Melilotus albus). Weeds should either be removed by hand or with the use of
herbicide. Both methods require that maintenance workers are fully capable of identifying non‐
native seedlings from native seedlings. All weeding shall occur before weeds flower and set seed.
At a minimum, weed removal will occur monthly during the winter and spring months (December‐
May) and will occur bimonthly during the summer and fall months (June‐November).
Maintenance Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sept. Oct. Nov. Dec.
Weeding X X X X X X X X X
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GENERAL IMPLEMENTATION SPECIFICATION
RESPONSIBILITIES AND QUALIFICATIONS
Owner/Applicant
Lennar Homes will be financially responsible for all aspects of this plan and is the owner/applicant
for the Sunbow II Phase 3 Amendment Project. Upon completion and final signoff of the
restoration effort, the City of Chula Vista will take ownership and management of the area as part
of the MSCP Preserve.
Revegetation Team
Implementation of this plan will require the use of qualified personnel including a Revegetation
Contractor and a Project Biologist. Work may occur by either a single firm or two firms, as long as
the following requirements are met.
Revegetation Contractor
The Revegetation Contractor shall have experience in native habitat restoration, having successfully
completed a minimum of three similar native habitat restoration projects. The contractor shall be
responsible for all site preparation, installation of plant materials, and any necessary maintenance
activities or remedial actions required during the installation and establishment period. The
contractor must be capable of distinguishing commonly encountered weeds (in all stages of
development) from native species to minimize or avoid impacts to target individuals.
Project Biologist
The Project Biologist shall have the following qualifications:
1. Bachelor’s degree in biology, botany, ecology or horticulture. A thorough understanding of
regulations regarding native habitats (i.e., native grassland, coastal sage scrub) and federally
listed species including Otay tarplant;
2. three years of local experience in identifying and sampling native vegetation including a
familiarity with native grassland and coastal sage scrub flora, habitat restoration, and Otay
tarplant biology;
3. two years of training and/or local experience in growing or working with the type of native
plant species used in this project (either in a nursery setting or in the field);
4. expertise in native grassland and coastal sage scrub ecology and knowledge of these
habitat’s flora, fauna, climate, soil, topography, hydrology, vegetation and wildlife, and how
these factors relate to the native habitat restoration efforts;
5. a thorough understanding of soil types in southern California that support native grassland,
coastal sage scrub, and Otay tarplant.
The Project Biologist will be responsible for monitoring all aspects of the restoration effort. Once
installed, the Project Biologist shall be responsible for monitoring the establishment of the site, and
for preparing reports documenting the status of the project. The Project Biologist shall assist the
owner with any decisions regarding the need for specific remedial actions during the monitoring
period, as well as short‐term maintenance activities.
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MAINTENANCE PROGRAM
The maintenance and monitoring program will continue for a period of 5 years following
implementation or until the project is given final approval by the Resource Agencies and the City.
The Revegetation Contractor will visit the site a minimum of six times a year (at one to two month
intervals, depending on the need) during the first four years and a minimum of three times during
year five. During each site visit, the Revegetation Contractor will remain at the site a sufficient
amount of time to complete the responsibilities specified in this section.
WEED CONTROL
As mentioned previously, weed removal will require constant diligence by the Revegetation
Contractor. Weeding is especially important for the first two years when native plants are most
susceptible to competition from non‐native species. Hand pulling and herbicide application shall be
used to control non‐native species. All herbicide shall be applied by a firm with a state of California
Pesticide Applicators License. All herbicide application shall be carefully applied to avoid impacts to
target species, especially Otay tarplant. All highly invasive exotic weed species noted on List A and
List B of the California Exotic Pest Plant Council (CALEPPC) list of Exotic Pest Plants of Greatest
Ecological Concern in California, shall be removed from the restoration area. Weeding shall focus
on limiting the build up of thatch that would preclude the establishment of Otay tarplant.
SUPPLEMENTAL WATERING
All restoration is expected to be dependent upon natural precipitation; however, a temporary
irrigation system will be installed to ensure establishment if rainfall is low during the winter and
spring months. All supplemental watering will be discontinued no later than the third year to
ensure that all target species become naturalized to the site.
TRASH AND DEBRIS
All restoration areas shall remain trash and debris free throughout the 5‐year maintenance and
monitoring period. All trash and debris shall be either recycled or disposed of at a certified landfill.
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MONITORING AND SUCCESS ASSESSMENT
MONITORING AND REPORTING
The primary goal of the restoration effort will be to restore native habitats favoring narrow endemic
clay associate plant species including Otay tarplant, and to meet mitigation standards for Orcutt’s
bird’s‐beak, decumbent goldenbush, and San Diego County viguiera. The mitigation elements of
the plan call for establishment of at least 91 Orcutt’s bird’s‐beak, 289 decumbent goldenbush, and
2,979 San Diego County viguiera (half the quantity of plants impacted by the Project). The Orcutt’s
bird’s‐beak and San Diego County viguiera will be planted in Diegan coastal sage scrub. The
decumbent goldenbush will be planted in both native grassland and coastal sage scrub areas. Otay
tarplant is to be planted in native grassland.
Monitoring will begin with the commencement of planned restoration activities and continue
through the end of the 5‐year maintenance and monitoring period.
Reference Site Monitoring
A reference site will be established within property’s open space preserve from which data will be
obtained and compared with identical information obtained from the restoration site in order to
determine project success. Given that Otay tarplant is an annual species and populations are
expected to naturally fluctuate from year to year depending upon climatic conditions, it will be
assumed that the reference site will provide a baseline from which to compare important variables
such as abundance, growth, flower production, pollinator presence, and habitat species
composition.
The selected reference site occurs within relatively high‐quality native grassland habitat located
near the northwest corner of the property (Figure 2). This area supports the greatest number of
Otay tarplant documented for the property and is considered to be similar in physical and chemical
characteristics to that of the proposed site (i.e., gentle north‐facing slope underlain by clay
soils). Specific sampling areas comparable to the size of the treatment areas will be established
within the reference site. Multiple sampling areas within both the restoration and reference sites
shall be established to capture site variability so that sampling areas are representative of both
sites.
Qualitative Monitoring
Qualitative monitoring will occur to document overall site health and provide information relative
to:
Plant Phenology – Annual species (Otay tarplant, Orcutt’s bird’s‐beak) life cycle including
germination, flowering, and seed. Information will be used to schedule the most
appropriate dates to conduct quantitative assessments.
Presence of pollinators – information will be gathered to determine presence and diversity
of pollinator species present.
Species Diversity – Plant species composition will be recorded to document diversity and
natural recruitment.
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Rainfall – Rainfall records will be obtained on a monthly basis from the nearest reliable
weather station. Rainfall amounts will be compared with data relative to annual plant
germination and flowering.
Thatch Build Up – thatch build up will be assessed during the summer/fall to ensure timely
removal occurs to avoid suppression of native plant germination.
Erosion Control – site erosion will be assessed to determine effective use of BMPs or
provide recommendations for alternative measures.
Presence of Site Debris/Trash – Any trash found on‐site will be recommended for removal
and proper disposal.
Irrigation Operation – Inspection of the irrigation system will occur during each qualitative
site assessment to ensure proper functioning.
In addition, qualitative monitoring will include supervision of all installation and subsequent
maintenance work to ensure that the project is being implemented properly to achieve prescribed
goals. This includes providing recommendations for remedial measures to ensure project success.
Duties of the Project Biologist shall include the following:
1. Verification of project boundaries to ensure that all existing native vegetation areas are
protected during the installation process and properly buffered during any herbicide
application programs;
2. Review and approval of all site preparation work including soil decompaction activities;
3. Review of re‐vegetation contractors order for all plant material;
4. Site approvals of all plant material;
5. Final site review at the completion of installation;
6. Preparation of the final installation and plant establishment check‐off lists;
7. Final approvals of installation, plant establishment, and maintenance and long‐term
remedial recommendations to ensure project success.
Quantitative Monitoring
Quantitative monitoring will occur on an annual basis to determine if performance standards are
being met or if any remedial measures are required to meet these standards. Monitoring methods
will be consistent throughout the 5‐year maintenance and monitoring period to ensure reliability
and comparison of data from year to year.
Otay Tarplant
Quantitative monitoring will occur at the peak flowering period of Otay tarplant as determined
from qualitative monitoring visits. Population counts will be obtained from the restoration area and
the designated reference site located near the northwest corner of the property. GPS equipment
will be used to record data points and polygons of Otay tarplant populations. Populations will be
determined based on groupings of individuals as defined as being within a distance of 4 meters of
each other. Otay tarplant populations containing less than 100 plants will be individually counted
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while populations of greater than 100 individuals will be estimated to the nearest 10. Total acreage
of occupied area at the restoration site will be calculated from mapped population boundaries.
Four twenty‐five meter transects will be established (staked) at both the reference site and the
restoration site. A one‐meter square quadrat will be used to estimate cover at each meter along
the transects. The placement of the quadrat will alternate to each side of the tape with each meter
intercept. Percent total vegetative cover, percent cover by species, and percent cover of bare
ground/dead will be estimated at each intercept. Percent cover will be estimated in 5%
increments above 5% cover, and 1% increments below 5% cover. In addition to measuring
cover, the quantity of Otay tarplant individuals including the number of flowering plants
occurring within each quadrat will be recorded and totaled for the transect.
Each year, Otay tarplant data recorded for the re storation site shall be compared with data
obtained from the reference site. The average annual percent change from year‐to‐year in
total quantity of plants and percent cover of flowering individuals at the restoration site
shall be compared to the sampled reference area.
Orcutt’s Bird’s‐beak
Quantitative monitoring will occur at the peak flowering period of Orcutt’s bird’s‐beak as
determined from qualitative monitoring visits. Population counts will be conducted only at the
restoration site. Mitigation will be considered successful if a minimum of 91 Orcutt’s bird’s‐beak
are counted within the restoration site during 3 of the 5 years of the maintenance and monitoring
period.
Decumbent Goldenbush and San Diego County Viguiera
Population counts of decumbent goldenbush and San Diego County viguiera will be conducted only
at the restoration site. Mitigation will be considered successful if a minimum of 289 decumbent
goldenbush and 2,979 San Diego County viguiera (half the quantity of plants impacted by the
Project) are established at the restoration site at the end of the 5‐year maintenance and monitoring
period.
Photographic Documentation
The Project Biologist shall further document the restoration effort utilizing photographic
monitoring. Photo points will be established at strategic locations that best depict the restoration
effort. Photographs will be taken each year from these photo points and provided in the annual
reports. Additional photographs shall be taken of the following activities:
1. Pre‐existing conditions prior to any restoration actions occurring;
2. Installation of erosion control devices;
3. Post‐installation of erosion control devices;
4. Hydroseed application;
5. Maintenance and monitoring of the restoration site;
6. Installation of signs and markers;
7. Installation of herbivore control devices;
8. Spring and summer growing activities;
9. Start and end points of the permanent transects (annually); and
10. Any other activities deemed to be significant with the restoration effort.
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Monitoring Schedule
Following installation, monitoring will occur per the following schedule:
Monitoring
Type
Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sept. Oct. Nov. Dec.
Qualitative X X X X X X X
Quantitative *X
* May vary depending on results of qualitative monitoring.
SUCCESS CRITERIA
Otay Tarplant
The goal of the restoration effort for Otay tarplant will be to enhance the proposed native grassland
restoration areas. The restoration targets expansion of the population with up to 836 Otay tarplant
individuals within 0.34 acre of clay enriched native grassland habitat. The proposed Otay tarplant
enhancement within the grassland restoration area is a goal of the restoration plan and not a
project compensatory mitigation standard. Therefore, there is no requirement to meet the
restoration goal in order to achieve the 5‐year sign off. Given that this species is an annual plant
and populations fluctuate due to climatic conditions, a reference site with recorded baseline
information will be used to compare with the restoration site to determine project success. The
following formula will be used to calculate minimum quantities of Otay tarplant for reaching the
goal:
Rn(I/R1) = X
I = Net loss of Otay tarplant from Project
R1 = Baseline population count at reference site
Rn = Population count at reference site in monitoring year n
X = Annual minimum goal for Otay tarplant population count at restoration site
The same formula will be used to determine the minimum goal for number of flowering plants. The
goal for Otay tarplant will be considered accomplished if the project minimum number of plants
and flowering individuals is achieved within the final 3 years of the 5‐year monitoring program.
Although the goal may be accomplished early, the full five years of maintenance and monitoring
described above will be conducted. If the restoration site count is less than that year’s
calculation, then the criteria will be concluded to not have been met for that maintenance and
monitoring year and recommendations will be made to assist with meeting the goals the following
year.
Habitat Area Goal
An additional goal of the project restoration effort will be to establish 1.71 acres of native grassland
and 3.13 acres of Diegan coastal sage scrub as shown on Figure 4.
Habitat Coverage Goal
In addition, percent cover of native species for each restored habitat shall have the goal of meeting
the following cover criteria:
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Table 6. Performance Goals for Vegetative Cover
Year 1
Implementation
Year 2 Year 3 Year 4 Year 5
% Cover of Native Grassland Species ‐‐‐‐ 30% 40% 50% 60%
% Cover Diegan Sage Scrub Species ‐‐‐‐ 30% 50% 60% 70%
Percentage coverage goals for native grassland are relative to the native species composition within
the reference site. Percentage coverage goals for Diegan Coastal Sage Scrub are based on direct
recorded coverage. If the site fails to meet the annual project success goal, the contractor will
implement remedial measures to ensure the restoration sites meet or exceed the project success
standards the following year.
In addition, no highly invasive exotic weed species listed by the California Exotic Pest Plant Council
(CALEPPC) will be allowed to occur within the restoration at anytime throughout the 5‐year
maintenance and monitoring period.
Project Mitigation Standards
The following standards are provided to comply with MM‐BIO‐ 1 of the project’s EIR and serve to
mitigate for impacts to Orcutt’s bird’s beak, decumbent goldenbush, and San Diego County viguiera.
Unlike the Otay tarplant and habitat restoration goals discussed above, the following standards are
provided for the purpose of mitigation.
Orcutt’s Bird’s‐beak
As mentioned previously, mitigation will be considered successful if a minimum of 91 Orcutt’s
bird’s‐beak are counted within the restoration site during 3 of the 5 years of the maintenance and
monitoring period.
Decumbent Goldenbush and San Diego County Viguiera
As mentioned previously, mitigation will be considered successful if a minimum of 289 decumbent
goldenbush and 2,979 San Diego County viguiera (half the quantity of plants impacted by the
Project) are established at the restoration site at the end of the 5‐year maintenance and monitoring
period.
If the site fails to meet project success standards, the Revegetation Contractor at the direction of
the Project Biologist will implement remedial measures each year to ensure the restoration site will
meet or exceed the project success standards the following year.
Annual Project Progress Reports
Throughout the maintenance and monitoring period, the Project Biologist will submit a monitoring
report by December 1st each year to Lennar Homes for submittal to the City of Chula Vista, U.S. Fish
& Wildlife Service, and California Department of Fish and Wildlife. This annual report will review
project progress to date based on identified success standards. The results of the annual report
would include information gathered from both the qualitative and botanical monitoring surveys.
When appropriate, remedial measures will be recommended for implementation during the
following year. A discussion of the statistical methodology (including confidence intervals) and the
results shall also be included in the annual reports.
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Remedial and Contingency Measures
The Biological Monitor will provide recommendations for remedial measures if success standards
are not met. These measures may include re‐seeding of areas, additional watering, additional weed
control, plant palette substitutions, and additional soil decompaction. These measures will be
discussed in the annual report for review by Lennar Homes.
If the restoration site is failing to meet the project success standards, the maintenance and
monitoring period with the continuance of remedial measures shall be extended. In the event the
Project Biologist is of the opinion that the mitigation will not reach success, alternative mitigation
shall be identified in consultation with Lennar Homes, City of Chula Vista, USFWS, and CDFW. These
recommendations would be provided in annual reports prepared by the Project Biologist in
consultation with Lennar Homes.
Long‐term Management
Following final signoff from the City and each of the resource agencies, the City will take
management responsibility as anticipated by the City’s Central City Area Specific Management Plan.
The long‐term management funding source for this area is CFD 98‐3.
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Merkel & Associates #94‐021‐33 23
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