HomeMy WebLinkAboutCT 00-20; Fox Miller Property; Tentative Map (CT) (3)FINAL
HABITAT RESTORATION AND MITIGATION PLAN
FOR DIEGAN COASTAL SAGE SCRUB, VALLEY
NEEDLEGRASS, WITH THREAD-LEAVED BRODIAEA,
AND SOUTHERN WILLOW SCRUB WETLAND
FOR THE FOX PROPERTY
CARLSBAD, CALIFORNIA
Prepared for
H.G. FENTON COMPANY
CONTACT: ALLEN JONES
7588 METROPOLITAN DRIVE
SAN DIEGO, CA 92108-4401
Prepared^by
ROBERT MacALLER
SENIOR BIOLOGIST
RECON NUMBER 3028B-2
NOVEMBER 23, 2005
1927 Fifth Avenue
San Diego, CA 92101-2358
619/308-9333 fax 308-9334 O This document printed on recycled paper RECON
TABLE OF CONTENTS
Introduction 1
Topography and Soils 7
Impacts and Mitigation Acreages 7
A. Diegan Coastal Sage Scrub 7
B. Valley Needlegrass Grassland 8
C. Thread-Leaved Brodiaea 8
D. Jurisdictional Wetlands 8
E. Non-Wetland Jurisdictional Waters 9
F. Southem Willow Scrub 9
Responsibilities 9
A. Owner/Project Proponent 10
B. Habitat Restoration Specialist 10
C. Grading Contractor 11
D. Plant Supplier 11
E. Seed Supplier 11
Revegetation 12
A. Coastal Sage Scrub 12
B. Valley Needle Grassland and Thread-Leaved Brodiaea
Habitat Creation and Enhancement 15
C. Wetland Creation and Restoration 19
D. Site Protection 24
Maintenance and Monitoring 25
A. Implementation Monitoring 27
B. General Maintenance Procedures 27
TABLE OF CONTENTS (cont.)
C. Qualitative Monitoring
D. Quantitative Monitoring
E. Monitoring Reports
F. Performance Standards
G. Notification of Completion
H. Estimated Habitat Mitigation Costs
28
30
31
31
33
34
References Cited 35
FIGURES
Regional Location
Project Location on USGS Map
Existing Biological Resources and Project Impacts
Proposed Mitigation
Wetland Creation Area
Permanent Fencing Plan
2
3
4
6
20
26
TABLES
1:
2:
3
4
6
7
8
9
10
11:
12:
13:
Project Impacts and Proposed Mitigation 5
Recommended Seed Composition and Application Rates for Diegan
Coastal Sage Scrub 13
Target Coastal Sage Scrub Species to be Salvaged 14
Coastal Sage Scrub Planting Densities 16
Thread-Leaved BrodiaeaA'^alley Needlegrss Salvage and Container Planting
Densities 18
Riparian Scrub Planting Densities 23
Seeding Location and Application Rates 23
Maintenance and Monitoring Schedule 27
Anticipated Exotic Species 29
Five-Year Performance Standards, as a Relative Percentage of Reference
Area Values for Coastal Sage Scrub Revegetation 32
Five-Year Performance Standards, as a Relative Percentage of Reference
Area Values for Riparian Revegetation 32
Five-Year Performance Standards, as a Relative Percentage of Reference
Area Values for Native Grassland 32
Habitat Restoration Cost Estimate 34
Introduction
This mitigation plan describes implementation guidelines, maintenance tasks, and
monitoring methods through which thread-leaved brodiaea (Brodiaea filifolia)
populations, Diegan coastal sage scrub habitat, native grassland habitat, and southem
willow scmb habitat can be restored as mitigation for impacts on the Fox Property. The
property is in the city of Carlsbad, Califomia located north of Palomar Airport Road, east
of El Camino Real, and between Faraday Avenue and College Boulevard (Figures 1
and 2). The project site includes a portion of Letterbox Canyon with its associated
drainages and the adjacent upland slopes. The site is bounded by El Camino Real to the
east and north with industrial development surrounding the rest of the site. A full
description of biological issues on this property is presented in Biological Technical
Report for the Fox Property Project (RECON 2001) with an update provided in the letter
titled REVISEI>-Summary of Revisions to Biological Resources Impacts and Proposed
Mitigation for Fox-Miller Property (RECON 2005).
The proposed development of this property will result in the loss of sensitive habitats.
Impacts include the loss of 0.11 acre (estimated at approximately 371,451 individuals) of
federally threatened and Califomia state endangered thread-leaved brodiaea habitat, 0.36
acre of native grassland, 2.66 acres of Diegan coastal sage scmb, 30.23 acres of non-
native grassland, and approximately 0.22 acre (2,500 linear feet) of U.S. Army Corps of
Engineers (USACE) and Califomia Department of Fish and Game (CDFG) jurisdictional
waters, including 0.03 acre of wetland habitat and 0.19 acre of non-wetland jurisdictional
waters of the U.S. (Figure 3). These impacts are considered significant and require
mitigation through habitat restoration (Table 1). Several areas in the proposed open space
have been identified for habitat restoration or enhancement (Figure 4).
Impacts to 2.66 acres of Diegan coastal sage scmb will be mitigated through on-site
preservation of 2.90 acres of Diegan coastal sage scmb habitat and conversion of 1.80
acres of non-native grassland to coastal sage scmb and revegetation of 0.62 acre of
manufactured slopes.
Impacts to thread-leaved brodiaea will be mitigated by a combination of on-site
preservation and translocation into restored habitat that will conserve 100 percent of the
thread-leaved brodiaea population. 95.1 percent of the population (89,543 square feet
[sq. ft.]; 2.05 acre) will be preserved; the remaining 4.9 percent (4,643 sq. ft.; 0.11 acre)
of the population will be translocated using the soil transfer method into restored valley
needlegrass grassland created from existing non-native grassland.
Impacts to valley needlegrass lands will be mitigated through the preservation of 0.07
acre and creation of 1.01 acre of native grassland in non-native grassland.
Pacific
Ocean
"^j^ Project location
0 Miles
kECON
M;\|obs\3028b\gis\gis rev\rtiitigation.apr\ hgl (regl) 05/20/05
FIGURE 1
Regional Location
Map Source: USGS 7.5 minute topographic map series, San Luis Rey quadrangle
V9 ))&r
E E D
-r
& • /\ '^^^
^irtoroja f ^ " " • 7 •/-''• -'
Country CllJll^ , ' ' / /• 51 '
0
Project location
Feef 2000 N
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FIGURE 2
Project Location on USGS Map
Image Source: Copvriaht_2004 AirPhotoUSA. Ml Rights Resen^e^ (fl^n^il 2004)
Project boundary
X / A Project impacts
RECON
Vegetation Communities
Diegan coastal sage scrub
HI Valley needlegrass grassland
I I Non-native grassland
I 1 Disturbed-ECR ROW
I I Developed
Jurisdictional USACE/CDFG Areas
Jurisdictional waters
j^H Wetland
Sensitive Species 0 Feet
Plil Thread-leaved brodiaea
300
M:\|obs\3028b\gis\gis rev\miiigation.apr
tlg3 (letter) 06/28/05"
California adolphia
I Coastal California gnatcatcher
(2000/2001 observation)
' Least Bell's vireo p,QURE 3
Existing Biological Resources
and Project Impacts
TABLE 1
PROJECT IMPACTS AND PROPOSED MITIGATION'
Biological Resource Existing Impacted Preserved
Mitigation
Ratio
Required
Mitigation
Acreage Proposed Mitigation
Vegetation Communities
Diegan coastal sage scrub
Non-native grassland
Sensitive Plant Resources
Thread-leaved brodiaea
Jurisdictional Waters
Disturbed wetland
Non-wetland jurisdictional
wetland
5.56
Valley needlegrass grassland 0.43
44.45
2.66
0.36
.30.23
2.90
0.07
14.22
0.03
0.21
0.03
0.19 0.02
2:1
3:1
0.5:
94,186 square 4,643 sq. ft. 89,543 sq. ft. 100 percent
feet (sq. ft.) (0.11 acre) (2.05 acre) conservation
(2-16 acre)
2:1
1:1
5.32 Preservation of 2.90 acres and conversion
of 1.80 acres of non-native grassland to
coastal sage scmb and restoration of 0.62
acre of manufactured slope..
1.08 Preservation of 0.07 acre and conversion
of 1.01 acre of non-native grassland to
native grassland with thread-lea\cd
brodiaea.
15.12 Preservation of 11.41 acres and native
conversion of 2.81 acres of non-native
grassland and restoration of 3.71 acres of
non-native grassland to native grassland.
4,643 sq. ft. 95.1 percent preservation of population in
(0.11 acre) place (89,543 sq. ft.; 2.05 acre);
transplantation of 4.9 percent of impacted
population (4.643 sq. ft.; 0.11 acre) into
open space on-site using soil transfer
method.
0.06 Creation and restoration of a 0.30-acre
Q IQ basin within Letterbox Canyon to a native
wetland habitat and purchase of 0.22 acre
of off-site credit at the Pilgrim Creek
Mitigation Bank.
Table is a revision of Table 8 found in the Revised Biological Technical Report for Fox Property. Carlsbad. California prepared by RECON (2001).
Image Source: Copyrighl 2004 Aii PholoL^, LLC,^II Rig^ts^Res^ve^^lown Ap^
Project boundary
Project Impacts
I I Ornamental
I I Picnic area
I I Developed area
j^H Off-site ROW
fl Off-site impact
RECON
Proposed Mitigation Areas
I I Thread-leaved brodiaea soil transfer site
I I Thread-leaved brodiaea/Native grass
Hfll Coastal sage scrub
flH Wetland creation area
I I Open space
Sensitive Species
^1 Thread-leaved brodiaea
M:\iobs\3023b\gis\gis rev\m'rtigation.apr
fig4 (mitigofionl 09/01/05
FIGURE 4
Proposed Mitigation
Impacts to non-native grassland will be mitigated through the preservation of 11.41 acres
on-site and restoration and conversion of 3.71 acres of non-native grassland to native
grassland. An in lieu fee shall be paid to the City of Carlsbad for the loss of non-native
grassland through the conversion to native habitat.
A total of 4.72 acres of native grassland will be created from the non-native grassland on-
site. This area will include the receptor site for the translocated brodiaea.
To mitigate for impacts to jurisdictional wetlands (at 2:1 ratio) and non-wetlands (at
1:1 ratio), 0.30 acre of southem willow scrub mitigation area be created on-site in a non-
wetland jurisdictional drainage.
Topography and Soils
Elevation of the site ranges from approximately 160 to 300 feet above mean sea level.
Letterbox Canyon runs east-west through the center of the site. Two side canyons, each
supporting a drainage, run north-south and join Letterbox Canyon in the western half of
the property.
Soils on the site consist of Altamont clay with 15 to 30 percent slopes for the entire
property. Altamont clay is derived from weathered calcareous shale and tends to be well-
drained (U.S. Department of Agriculture 1973).
Impacts and Mitigation Acreages
Brief descriptions of botanical resources and jurisdictional areas addressed in this
document are included below.
A. Diegan Coastal Sage Scrub
Diegan coastal sage scrub is comprised of low-growing, aromatic shrubs that are drought
deciduous. Diegan coastal sage scmb is found in coastal areas from Los Angeles County
south into Baja Califomia (Holland 1986).
There are approximately 5.65 acres of Diegan coastal sage scmb on the project site: 2.66
acres will be impacted by development and the remaining portion (2.90 acres) preserved
as open space and 1.80 acres shall be restored from non-native grasslands and 0.62 acre
revegetated on a manufactured slope (see Figure 4). All coastal sage scmb restoration
areas on manufactured slopes are located outside of the fuel management zones. Black
sage (Salvia mellifera) and common encelia (Encelia californica) dominate the
community. Other species present include Califomia sagebmsh (Artemisia californica).
coyote bush (Baccharis pilularis), Califomia adolphia (Adolphia californica), and
Califomia buckwheat (Eriogonum fasciculatum).
B. Valley Needlegrass Grassland
Valley needlegrass grasslands are comprised of native perennial bunch grasses. The on-
site vegetation community has been mainly converted to non-native annual grasslands
through invasion of exotic annual grasses. Valley needlegrass grasslands often have a
large component of non-native grasses but are distinguished as native grasslands if the
cover by native grass species is 10 percent or greater.
Five patches of valley needlegrass grassland totaling 0.43 acre are scattered throughout
the site within the non-native grassland. Approximately 0.36 acre will be impacted by
construction, with the remaining portion (0.07 acre) saved in the project open space and
1.01 acre restored from conversion of non-native grassland. The native species include
purple needlegrass (Nassella pulchra) and foothill needlegrass (Nassella lepida) and
comprise approximately 10 percent of the habitat. Non-native grasses, such as wild oats
(Avena sp.) and Italian ryegrass (Lolium multiflorum), are the dominant species within
this plant community.
An additional 3.71 acres of non-native grassland will be restored to native grassland as
part of the mitigation requirements for impacts to non-native grassland for a total of 4.72
acres.
C. Thread-Leaved Brodiaea
Thread-leaved brodiaea, a state-listed endangered and a federally listed threatened
species, is a perennial plant typically occurring on hillsides or in valleys in grassland
communities with clay, loamy sand, or alkaline silty-clay soils (U.S. Fish and Wildlife
Service [USFWS] 1998). An area of 94,186 sq. ft. (2.16 acres) of thread-leaved brodiaea
was identified during vegetative surveys conducted during 2005. 95.1 percent of the
population (89,542 sq. ft; 2.05 acre) will be preserved; the remaining 4.9 percent
(4,643 sq. ft.; 0.11 acre) of the population will be translocated using the soil transfer
method into restored valley needlegrass grassland created from existing non-native
grassland.
D. Jurisdictional Wetlands
The two wetland areas on the property (totaling 0.03 acre) will be directly impacted by
site development (see Figure 3). For a complete discussion of jurisdictional resources on-
site see the wetiand delineation for the project (RECON 2001) One wetland area is
located in the western end of Letterbox Canyon. This drainage is confined by the recently
constmcted detention basin which floods frequently but holds water for relatively short
periods of time. Earth-moving activities resulting from the recontouring of the basin may
have dismpted surface soils. Although the top 12 inches lack hydric soil indicators, soil
characteristics below 12 inches are typical of wetlands and include sulfidic odor, organic
streaking, and bluish-gray mottling. The majority of plant species here are considered
facultative wetland species such as grass poly (Polypogon monspeliensis), tamarisk
(Tamarix sp.), and bristly ox-tongue (Picris echioides). Wetland hydrology indicators
such as water marks and oxidized root channels were also found.
The second wetland area is a localized natural ponding area that occurs at the head of the
westemmost side drainage. Soils exhibited a strong sulfidic odor and moderately sized
low-chroma (grayish color) mottles typical of reducing conditions in wetland soils. Strong
hydrology indicators such as sediment deposits and saturated soils also occurred here.
E. Non-Wetland Jurisdictional Waters
Constmction will impact 0.19 acre of non-wetland jurisdictional waters on Fox Property.
The property is currently bisected by the Letterbox Canyon drainage, which conveys
flows in a westerly direction. The vegetation on-site within areas designated as non-
wetland jurisdictional waters are mostiy upland species such as lemonadeberry (Rhus
integrifolia), black mustard (Brassica nigra), and coyote bush.
F. Southern Willow Scrub
Southem willow scrub will be created in a 0.30-acre detention basin to mitigate impacts
to jurisdictional wetiands and non-wetland waters. This is a riparian conmiunity
considered sensitive habitat by the CDFG and USACE. The dominant plant species in
this community are willows. The density of willows typically prevents a developed
understory from growing (Holland 1986). This vegetation community is typically found
along major drainages but occurs in small drainages as well. Typical species occurring in
the vicinity of the project site include arroyo willow (Salix lasiolepis), mule fat
(Baccharis salicifolia), western ragweed (Ambrosia psilostachya), blue elderberry
(Sambucus mexicana), and others.
Responsibilities
H.G. Fenton Company is responsible for implementing the mitigation project and meeting
the final success criteria. Once the success criteria have been achieved and the project has
been accepted as complete, the open space/mitigation lands (Lot 5) on the property will
be dedicated to the City of Carlsbad or a conservation entity designated by the City,
which will be responsible for the conservation of the site in perpetuity.
A. Owner/Project Proponent
The owner/project proponent shall provide detailed construction drawings, accurate
timelines, and written project specifications in conformance with this plan. The
owner/project proponent shall be responsible for funding all aspects of the project
including implementation, long-term maintenance, and remedial actions as determined by
the following regulatory agencies: USFWS, the CDFG, the USACE, the Regional Water
Quality Control Board (RWQCB), and the City of Carisbad.
If portions of the restoration areas are sold, the new owner/project proponent shall assume
all responsibilities described in this document, unless otherwise agreed to between the
parties.
The owner/project proponent shall be responsible for coordination between the grading
contractor and habitat restoration specialist to ensure habitat restoration occurs on the
proper schedule. The owner/project proponent shall manage project activities in the best
interest of restoration goals. The owner/project proponent will be solely responsible for
administration of project contracts with the habitat restoration specialist and grading
contractor. Decisions to stop work are the responsibility of the owner/project proponent,
except where noted herein. The owner/project proponent shall have sole authority in
decisions to suspend payment or terminate contracts, and will hire another restoration
specialist to ensure that the Wildlife Agency-approved success criteria are met. This
includes all phases of project installation, long-term maintenance, and biological
monitoring. The owner/project proponent may, with sole discretion at any time, replace
the contractors, if necessary.
B. Habitat Restoration Specialist
The habitat restoration specialist will be an individual or team of individuals with a
minimum of two years experience in upland and riparian community restoration,
monitoring, and reporting. The habitat restoration specialist will be retained during the
project to perform the following tasks, and be responsible for implementing the
revegetation plan in accordance with its specifications:
• Consult with the contractor on any activities that may be dismptive to the mitigation.
• Attend pre-grading and preconstmction meetings to consult with the owner/project
proponent and grading contractor and to educate the contractors on revegetation goals
and habitat sensitivity.
10
• Implement plant salvaging, seed collection, propagation, and site planting, or approve
and monitor qualified subcontractors in execution of aspects of this plan.
• Implement required long-term maintenance of the mitigation area as defined herein.
• Oversee and perform the required monitoring and reporting in accordance with the
procedures established in this plan.
C. Grading Contractor
• The grading contractor shall closely coordinate the grading schedule with the habitat
restoration specialist to ensure all preparatory measures are in place prior to impacting
existing habitat.
• Grade the mitigation sites in accordance with this revegetation plan.
D. Plant Supplier
The plant supplier must have at least two years experience in propagating native plants
for upland and wetland restoration projects.
• The plant supplier will produce properly aged plants in one-gallon containers ready
for outplanting.
• All plants will be produced from seed collected on or adjacent to the site and
inoculated with mycorrhizae.
E. Seed Supplier
The seed supplier must have at least two years' experience collecting coastal sage scmb
and riparian seeds for restoration projects.
• Only species specified in this mitigation plan, under the supervision of the habitat
restoration specialist, will be collected.
• Seed will be collected from the project site, whenever possible. The range of seed
collection will be limited between Camp Pendleton and Encinitas and no further than
10 miles inland.
11
Revegetation
Approximately 7.44 acres of lands will be restored to native habitat or enhanced. The
following sections describe the techniques that will be utilized for site preparation, seed
collection, plant production, plant salvage, planting, irrigation and initial maintenance for
Diegan coastal sage scrub; thread-leaved brodiaea and valley needlegrass land restoration
and enhancement; and wetland creation. Portions of this plan involve the salvage of
sensitive species during specific times of year. Construction of the development will be
delayed until these tasks are completed.
A. Coastal Sage Scrub
Within the on-site open space preserve, 1.80 acres of non-native grassland and 0.62 acre
of manufactured slopes will be converted to Diegan coastal sage scrub (see Figure 4).
Non-native grassland on the margins of an existing patch of Diegan coastal sage scmb,
located on the northwest portion of the project site, will be used for the creation. In
addition to creating more square footage, expansion of the existing patch will increase
habitat value beyond the current conditions.
1. Mitigation Site Description
Presently, the non-native grassland community consists of sweet fennel (Foeniculum
vuigare), black mustard, (Brassica nigra), brome grasses (Bromus spp.), and wild oats
(Avena spp.). This non-native grassland community has lower habitat functions and
values than the Diegan coastal sage scrub it will be replaced with.
2. Mitigation Site Preparation
The coastal sage scmb restoration areas will undergo a grow-and-kill regime for non-
native species. Between late summer and early winter, after seed has set but prior to
brodiaea growth, non-native species will be removed using line trimmers. All exotic
material will be raked and removed from the site. As weedy species begin to grow and are
distinguishable from the brodiaea, a qualified pesticide applicator, trained to recognize
thread-leaved brodiaea and under the supervision of the habitat restoration specialist, will
spot-apply an appropriate herbicide (such as Roundup®) directly to the non-native
species. The remaining areas will be weeded by hand so as not to kill any rare plants.
3. Seed Collection and Application
Seed collection will begin as soon as possible prior to implementation of revegetation
(preferably six months before). Seed collection will be limited to a 10-mile radius of the
property. Target species and application rates are presented in Table 2. ff seed of a
particular species is not available at the time of seed collection or application, the habitat
12
TABLE 2
RECOMMENDED SEED
COMPOSITION AND APPLICATION
RATES FOR DIEGAN COASTAL SAGE SCRUB
Scientific Name Lbs./Acre
Artemisia californica ^ ^
Califomia sagebrush
Encelia californica j ^
Conunon encelia
Eriogonum fasciculatum j ^
Califomia buckwheat
Grindelia camporum ^ ^
Gumplant
Hemizonia fasciculate Q ^
Tarplant
Isocoma menziesii
Coast goldenbush
Malosma laurina
Laurel sumac
1.0
0.5
Mirabiiis californica ^ ^
Wishbonebush
Nassella pulchra Q
Purple needlegrass
Rhus integrifolia ^ ^
Lemonadeberry
Salvia mellifera ^ Q
Black sage
Sisyrinchium bellum j ^
Blue-eyed-grass
restoration specialist may make substitutions, as approved by the City of Carlsbad and
Wildlife Agencies.
Prior to planting the site, it will be hydroseeded with these locally collected grasses,
annuals, and perennials. Seed shall be applied to prepared revegetation area between
November 15 and January 15. The hydroseed mix will contain M-binder, which does not
prolong seed germination. The organic binder should be applied at a rate of
200 pounds/acre with 2,000 pounds/acre of wood fiber. The seed/slurry will be mixed
thoroughly before, and continuously during, application. Prior to mixing hydroseed
ingredients, the tank and hose used to apply the hydroseed mix will be thoroughly rinsed
with water at least three times to ensure any previous seed mix is removed. After the
initial cleaning, the tank does not require washing between batches, providing the same
hydroseed mix is being applied. The hydroseed mix will be applied in an even and
consistent manner.
4. Native Plant Salvage
In conjunction with salvage efforts for the thread-leaved brodiaea, other species from the
coastal sage and native grassland impact areas will be salvaged for planting. This will
allow the introduction of mature and unevenly aged plants with developed root systems
and intact symbiotic associations, into the revegetation areas. A list of species targeted for
salvage are included in Table 3. The habitat restoration specialist will determine and
identify specimens that area appropriate for salvage. Plants will be removed from the
ground using hand tools or a back loader to remove the root ball and surrounding soil, ff
necessary, plants will be transplanted and stored in soil at a temporary nursery, located
on-site, unit the revegetation areas are prepared for planting and all signs of transplant
shock have subsided. Whenever possible individuals will be removed from a designated
grading area and replanted without delay in a prepared revegetation site.
TABLE 3
TARGET COASTAL SAGE SCRUB SPECIES TO BE SALVAGED
Scientific Name Common Name
Adolphia californica Adolphia
Artemisia californica Califomia sagebrush
Encelia californica Common encelia
Marah macrocarpus Wild cucumber
Mirabiiis californica Wishbone bush
Nasella pulchra Purple needlegrass
Opuntia littoralis Shore cactus
Opuntia prolifera Cholla
Salvia mellifera Black sage
Sisyrinchium bellum Blue-eyed grass
Yucca schidigera Mojave yucca
14
5. Plant Production
To supplement plant salvaging, container stock of Diegan coastal sage scmb species will
be grown from the locally collected seed in a native plant nursery under the supervision of
the habitat restoration specialist. New plants will be grown each year of the entire five-
year monitoring period to replace dead individuals and improve densities in restoration
and enhancement areas. The container stock will be inoculated with mycorrhizae using
native topsoil. The number of container stock to be produced will vary depending on the
number of individuals salvaged. Collectively, container plants will be planted at the
minimum densities presented in Table 4.
6. Irrigation
Transplants will receive approximately one gallon of water, delivered by a water tmck, at
the time of planting. One-half gallon will be applied to the planting hole and allowed to
infiltrate into the soil. The other one-half gallon will be applied to the installed plant.
Watering by hand or using a water tmck will continue as directed by the habitat
restoration specialist. All irrigation shall cease at least one-year before requesting that the
City and Wildlife Agencies sign-off on the restoration.
B. Valley Needle Grassland and Thread-Leaved
Brodiaea Habitat Creation and Enhancement
Thread-leaved brodiaea typically occurs in needlegrass grasslands. Approximately
4.72 acres of the site that is currently a non-native grassland will be restored to a valley
needlegrass grassland. This area currently supports a large population of thread-leaved
brodiaea. Included within the 4.72 acres is a 0.11-acre site that will be the receptor site to
receive the 0.11 acre area of thread-leaved brodiaea proposed for impact.
Construction implementation shall be delayed until the plant salvage component of this
section has been completed.
1. Mitigation Site Conditions
Thread-leaved brodiaea is currently found in the non-native grassland community
primarily on the northem portion of the project site with a few scattered areas in the
southem portion of the property (see Figure 3). This area contains sweet fennel, black
mustard, brome grasses, and wild oats. The 0.11 acre of thread-leaved brodiaea proposed
for impact will be translocated using the soil transfer method into a suitable receptor site.
The receptor site chosen (see Figure 4) was an area that did not exhibit any winter
vegetative growth of thread-leaved brodiaea during the 2005 season, but located
immediately adjacent to areas that did support brodiaea. ff deemed necessary in the field.
15
TABLE 4
COASTAL SAGE SCRUB PLANTING DENSITIES
Species Planting
Scientific Name Number and Size per Acre*
Adolphia californica
Califomia adolphia
Artemisia californica
Califomia sagebmsh
Malosma laurina
Laurel sumac
Mirabiiis californica
Wishbonebush
Rhus integrifolia
Lemonadeberry
Salvia mellifera
Black sage
Yucca shidegera
Mojave yucca
100 one-gallon
300 one-gallon
50 one-gallon
75 one-gallon
Nassella lepida »,„ r • . ,, 250rour-mch Valley needlegrass
Nassella pulchra .,i-r. x- • L „ , „ 250four-mch Purple needlegrass
Opuntia littoralis , „„ „ „, 100 flats Shore cactus
Opuntia prolifera ^^^^^^
Cholla
25 one-gallon
100 one-gallon
Sisyrinchium bellum , r • L . 100 four-mch Blue-eyed-grass
50 one-gallon
*If not from salvage.
the exact location and configuration of the receptor site may change slightly as the
restoration activities are implemented (see Figure 4).
Impacts to valley needlegrass grassland and non-native grassland will be partially
mitigated through the on-site conversion of 4.72 acres of non-native grassland to native
grassland (see Figure 4). The location of this restoration was chosen to include and
surround the thread-leaved brodiaea receptor site and to enhance high quality areas that
support dense patches of brodiaea.
2. Site Preparation
The enhancement and creation area will undergo a grow-and-kill regime for non-native
species. Each aboveground brodiaea population will be clearly flagged. Between late
summer and early winter, after seed has set but prior to brodiaea growth, non-native
species will be removed using line trimmers. All exotic material will be raked and
removed from the site. As weedy species begin to grow and are distinguishable from the
brodiaea, a qualified pesticide applicator, trained to recognize thread-leaved brodiaea and
the under supervision of the habitat restoration specialist, will spot apply an appropriate
herbicide (such as Roundup®) directly to the non-native species, excluding a 10-foot
diameter around each flagged brodiaea. The remaining areas will be weeded by hand so
as not to kill any rare plants. This process will be repeated until the brodiaea are ready to
be translocated.
3. Plant Salvage and Seed Collection
All areas of thread-leaved brodiaea within the proposed development as mapped during
the January and Febmary 2005 vegetative surveys, will be salvaged and translocated to
the restoration site using the soil transfer method. The mapped areas of impact will be
relocated and marked in the field by a qualified restoration specialist using a Global
Position System (GPS). The receptor site will be marked in the field and prepared for
transfer, which will include the creation of receptor pits consistent in size to the patches
of brodiaea to be salvaged and transferred. Under the direction of a qualified
biologist/habitat restoration specialist, an equipment operator will cleanly excavate each
distinct brodiaea population in the impact area. The operator will remove intact clumps of
soil containing the brodiaea corms using an excavator bucket and replace them into the
prepared receptor pits. After intact clumps of thread-leaved brodiaea are removed for
translocation, a monitoring biologist will look through the soil to ensure that no corms
remain. Any remaining corms will be planted next to the thread-leaved brodiaea clumps
in the receptor area.
In conjunction with salvage efforts for the thread-leaved brodiaea, other species from the
coastal sage and native grassland impact areas will be salvaged for planting. A list of
17
TABLE 5
THREAD-LEAVED BRODIAEA/VALLEY NEEDLEGRSS
SALVAGE AND CONTAINER PLANTING DENSITIES
Species Number and Size per Acre*
Blue-eyed-grass
Sisyrinchium bellum
Thread-leaved Brodiaea
Brodiaea filifolia
Califomia adolphia
Adolphia californica
Cholla
Opuntia prolifera
Mojave yucca
Yucca schidigera
Purple needlegrass
Nassella pulchra
Nassella lepida
Valley needlegrass
Shore cactus
Opuntia littoralis
100 four-inch
All available
20 one-gallon
50 flats
10 four-inch
500 four-inch
500 four-inch
10 flats
*If not from salvage.
species targeted for salvage and planting in the valley needlegrass/thread-leaved brodiaea
community and planting densities are included in Table 5.
4. Plant Production
To supplement plant salvaging, thread-leaved brodiaea will be grown from seed in a
native plant nursery under the supervision of the habitat restoration specialist. Seed will
be collected from plants located on-site within the open space. New plants will be grown
each year of the entire five-year monitoring period to replace dead individuals and
improve densities in restoration and enhancement areas.
5. Irrigation
Transplants will receive approximately one gallon of water, delivered by a water tmck, at
the time of planting. One-half gallon will be applied to the planting hole and allowed to
infiltrate into the soil. The other one-half gallon will be applied to the installed plant.
Watering by hand or using a water tmck will continue as directed by the habitat
restoration specialist. All irrigation shall cease at least one-year before requesting that the
City and Wildlife Agencies sign-off on the restoration.
C. Wetland Creation and Restoration
1. Goal of Mitigation
The purpose of this wetland creation is to replace functions and habitat lost from impacts
to wetlands and non-wetland jurisdictional waters on-site. The quality of the created
habitat will exceed that of the existing wetland habitat. This mitigation will create
0.30 acre of southem willow scmb in place of non-wetland jurisdictional waters and
exotic-dominated wetland that has emerged in an artificially created depression
(Figure 5). A detention basin will be created within a portion of Letterbox Canyon,
remaining as open space and revegetated with willow scmb species. This basin will be
supported by natural water and mnoff from the adjacent developed areas. This proposed
mitigation would provide for a net increase in wetland acreage on-site and an increase in
habitat values beyond extant conditions.
2. Types of Habitat to be Created
Impacts to 0.03 acre of jurisdictional wetlands and 0.19 acre of non-wetland jurisdictional
waters will be mitigated on-site through the creation of 0.30 acre of southem willow
scmb in the westem portion of Letterbox Canyon, a non-wetland jurisdictional drainage
currently vegetated with coastal sage scmb (2:1 mitigation of wetland and 1:1 mitigation
of non-wetland). Impacts to coastal sage from wetland creation will be mitigated at
1:1 through on-site preservation. Southem willow scmb will be created by planting and
19
0 Feef 100
Wetland creation area
RECON
FIGURE 5
Wetland Creation Area
M:\iobs\3028b\gis\gis rev\mitigation.apr\
figS (creation) 05/20705
seeding with species such as arroyo willow, mule fat, westem ragweed, blue elderberry,
and others. Native species will be introduced using cuttings, seeds, and salvaged plants
collected from the local vicinity, as well as nursery-grown container stock produced from
locally collected seed.
3. Functions and Values of habitat to be Created
The proposed wetiand mitigation would provide cover, nesting, and foraging
opportunities for many of the local wildlife species including birds, insects, amphibians,
and mammals. The detention basin established at the eastern end of Letterbox Canyon
will improve water quality in the drainage.
4. Time Lapse
Implementation of revegetation will be limited to October 1 to April 30 in order to
coincide with appropriate weather conditions. Creation of a functioning southem willow
scmb community is expected to take approximately four to five years. Implementation of
the wetland restoration shall be completed no later than nine months following the close
of the calendar year in which impacts first occur or by March 31, 2006, whichever comes
first.
5. Final Success Criteria
The mitigation areas will be monitored for five years following the completion of
revegetation implementation. The mitigation site shall attain 80 percent native cover, 80
percent density, and 80 percent diversity relative to a target southem willow scrub
community selected by the habitat restoration specialist from within a 10-mile radius of
the project site.
The target community will be selected prior to revegetation implementation after the
approval of a final plan. This will allow the habitat restoration specialist to select the
proper riparian community for the specific site conditions as a target. The target
community will be considered high quality, that is, a high coverage of native species with
little to no exotic species present. The specific target functions and values will be
included in the final revegetation plan.
6. Target Hydrological Regime
Precipitation mnoff from the proposed constmction pads, manufactured slopes supporting
the road, and existing vegetated slopes (see Figure 6) will flow into letterbox canyon. The
outflow of water from the property is currently blocked at the westem end of the canyon
by a manufactured slope located off the property. This manufactured slope effectively
acts as a dam. An outfall pipe will direct water through this slope and away from the
basin to prevent long-term flooding. The outfall pipe will cause the water to flow out of
21
the western end of the property to join with the existing drainage there. The wetland
creation area will be designed to receive runoff from existing slopes vegetated with
coastal sage scrub or revegetated coastal sage scrub and manufactured slopes revegetated
with coastal sage scrub species.
7. Target Jurisdictional Acreage Created
This mitigation will create 0.30 acre of southern willow scmb in place of non-wetland
jurisdictional waters and exotic-dominated wetland that has emerged in an artificially
created depression.
8. Existing Functions and Values of Mitigation Area
The proposed mitigation site is a non-wetland jurisdictional drainage vegetated with
coastal sage scmb. The vegetation on-site within areas designated as non-wetiand
jurisdictional waters are mostly upland species such as lemonadeberry (Rhus integrifolia),
black mustard (Brassica nigra), and coyote bush. Although the drainages lack wetland
vegetation, there is strong evidence of seasonal flows (i.e., cut banks and the presence of
an ordinary high water mark). The widening of the stream bottom to accommodate the
increase in water flow from runoff will result in the loss of some coastal sage scrub.
Occasional hikers currently use the area with little other activity evident.
9. Implementation
Heavy equipment will be used to create a 0.30-acre creation area and a detention basin to
receive mnoff from the slopes. The habitat restoration specialist will be on-site during
creation to ensure that no unintended impacts to the coastal sage scmb occur. Wetland
creation will be implemented between September 16 and February 15 to avoid coastal
Califomia gnatcatcher nesting season, other nesting birds, and heavy late winter rains.
This revegetation plan will use cuttings and salvaged plants collected from the local
vicinity, as well as some nursery-grown container plants grown from locally collected
seed. Control of invasive exotic weeds during the maintenance period will also be an
important component of the plan.
a. Plant Materials
Willow and mule fat cuttings will be taken from trees within a 10-mile radius of the
development. These cuttings will be taken to the greenhouse and allowed to root in one-
gallon containers for planting at the wetland creation site. Blue elderberry, California
sage, Califomia adolphia (Adolphia californica), and shore cactus will be planted along
the upland edges of the basin. Cuttings and container plant densities are presented in
Table 6. Installation of native plants will begin after creation of the wetland mitigation
area. Plant installation will be limited to the months of October through Febmary.
22
b. Seed Collection and Application
Seed collection should begin at least six months prior to revegetation implementation.
Target species and application rates are presented in Table 7.
Following installation of salvaged and container plants, the mitigation sites will be seeded
with locally collected annuals and perennials. Seed will be applied by hand to prevent
disturbance of transplants.
TABLE 6
RIPAIOAN SCRUB PLANTING DENSITIES
Number and Total Number
Species Size per Acre for 0.25 Acre
Arroyo willow
Salix lasiolepis 300 one-gallon 75
Black willow
Salix gooddingii 200 one-gallon 50
Sand-bar willow
Salix exigua 100 one-gallon 25
Califomia sage
Artemisia californica 100 one-gallon 25
Blue elderberry
Sambucus mexicana 50 one-gallon 13
Shore cactus
Opuntia littoralis 25 flats (salvaged) 6
Mule fat
Baccharis salicifolia 200 one-gallon 50
TABLE 7
SEEDING LOCATION AND APPLICATION RATES
Species Seeding Location Pounds/Acre Total for 0.25 Acre
Califomia sagebrush Bank 2 0.50 Artemisia californica Bank 2 0.50
Gumplant
Grindelia camporum Bank/floor 2 0.50
Arroyo willow
Salix lasiolepis Floor 2 0.50
Mule fat
Baccharis salicifolia Bank/floor 3 0.75
Coast goldenbush
Isocoma menziesii Bank/floor 1 0.25
Blue elderberry
Sambucus mexicana Bank 2 0.50
Westem ragweed
Ambrosia psilostachya Bank/floor 1 0.25
23
c. Irrigation
Installation of irrigation helps to ensure that restoration areas meet the performance
standards in five years. Providing supplemental water during periods of winter drought
increases survivorship of newly installed plants. The goal is to withdraw supplemental
water as soon as plants have established so they can adapt to natural environmental
conditions. Therefore, water use is expected to be highest during the first growing season,
tapering off until no supplemental water is necessary.
A temporary irrigation system shall be installed in the southem willow scmb restoration
area. The irrigation shall be installed prior to planting and seeding activities. The habitat
restoration specialist shall work with the irrigation technician to set up an irrigation
schedule to meet the specific conditions present in the field following wetland creation.
Changes to the irrigation schedule may only be initiated by the habitat restoration
specialist.
When the habitat restoration specialist determines that plants have become established,
irrigation will be discontinued. Following termination of irrigation, the system shall be
removed from the site. All irrigation shall cease at least one-year before requesting that
the City and Wildlife Agencies sign-off on the restoration.
d. As-Built Report
An as-built report will be prepared and submitted to the regulatory agencies within 90
days of completion of implementation activities. The as-built report covers the time
period from when grading of the restoration site begins to the end of the main planting
activities.
The as-built report will document exactiy what was done to prepare the site for
restoration and to plant and seed the site. Throughout constmction of the restoration site,
the habitat restoration specialist will keep records that will include the dates of site
preparation, installation of container plants, and application of seeds, and describe the
location and condition of the reference site. The as-built report will include these records
and address any significant problems encountered or necessary changes made in the field.
The as-built report will also include photographs of the restoration activities.
D. Site Protection
Prior to constmction, temporary fencing will be installed when grading or clearing is to
occur within 100 feet of preserved habitat, located on- or off-site. All temporary fencing
shall be removed after the conclusion of all constmction activities. A qualified biological
monitor should be on-site when the temporary fencing is erected and periodically during
24
constmction to ensure project limits are not exceeded. The monitor will prepare reports
demonstrating that project limits were not exceeded.
A permanent chain link fence will be installed along the interface of the open space and
development to protect revegetation work and the open space from vandalism (Figure 6).
No seeding or translocation of sensitive plant species will be performed prior to the
installation of fencing around each site. Silt fence will be installed, as necessary, on each
mitigation site where steep slopes and potential erosion could create sedimentation in
existing adjacent native habitat. The protection fence will remain in place and maintained
until the end of the five-year monitoring period. Access gates for the purpose of
maintenance and monitoring of the open space preserve should be installed at appropriate
locations, as necessary. All gates will remain locked except while construction or
maintenance personnel are on-site. Project signs will be placed on the fence at locations
where unauthorized entry is most likely. Along public rights-of-way, signage shall occur
no less than every 1,000 feet. Signs bolted to the fence will provide notice that the area is
an ecological preserve, that trespassing is prohibited, and cite penalties for trespass
violation, including liability for repair of any damage within the fenced area such as
disturbance of soil or vegetation. Signs will also identify the restoration project and a
contact for additional information.
Maintenance and Monitoring
The objectives of the maintenance and monitoring program are to ensure successful
habitat establishment and development of an information base, which documents the
maintenance and monitoring efforts. To achieve these objectives, the habitat restoration
specialist will observe and direct revegetation implementation, maintenance, and
monitoring activities.
The monitoring and maintenance period will begin immediately upon completion of plant
installation and will last for a period of five years as presented in Table 8. The
maintenance program will ensure that debris removal, weed control, replanting and
reseeding, site protection, and other tasks are adequately performed. Maintenance
measures will be conducted by the habitat restoration specialist as outlined below for all
restoration and enhancement areas.
25
Projed boundary
Chain link fence
Project Impacts Proposed Mitigation Areas
• Ornamental • Thread-leaved brodiaea soil transfer site
_J Picnic area Thread-leaved brodioeo/Notive gross
Developed area Coastal sage scrub
•i Off-site ROW •• Wetland creation area
•• Off-site impact I | Open space
RECON
M:\iobs\3028b\gis\gis rev\mitigati
fig6(fencing) 1T/23/05 on.apr
FIGURE 6
Permanent Fencing Plan
TABLE 8
MAINTENANCE AND MONITORING SCHEDULE
Type/Task Year 1 Year 2 Year 3 Year 4 Years
Maintenance
Trash removal Monthly Quarterly Quarterly Quarterly Quarterly
Weed control As-needed As-needed Quarterly Twice a year Twice a year
Fence maintenance Monthly Monthly Monthly Monthly Monthly
Irrigation As-needed As-needed As-needed As-needed -
Implementation
Monitoring Duration of implementation
Qualitative
Monitoring Monthly Monthly Quarterly Quarterly Quarterly
Quantitative
Container plant survival Quarterly Annually Annually Annually Annually
Spring vegetation sampling -Annually Annually Annually Annually
A. Implementation Monitoring
To ensure that conditions of this revegetation plan are adhered to, all implementation
activities will be monitored and recorded by the habitat restoration specialist. The
biologist will be available on-site during revegetation implementation to assist in making
necessary plan modifications so the work may proceed. Records will include dates of
translocation of salvaged species, container plantings, and seeding. These, along with any
significant problems encountered or necessary changes made to the plan, will be included
in the first annual report.
B. General Maintenance Procedures
1. Vegetation Clearing and Trash Removal
Pmning of any native vegetation or removal of dead wood and leaf litter shall not be
allowed in the revegetation and enhancement areas. Trash will be removed from the sites
by hand on a monthly basis for the duration of the first year and quarterly thereafter.
Trash consists of all man-made materials, equipment, or debris left within the
revegetation or enhancement areas that is not serving a function related to revegetation.
2. Weed Control
Weed control will continue throughout the five-year monitoring period. Hand weeding or
other weed control methods will be performed by maintenance workers familiar with and
trained to distinguish weeds from native species. During the first year, weeding will be
performed quarterly (or more often as determined by the habitat restoration specialist) to
keep weeds from producing seeds and to control weed competition during the
27
establishment period of native plants. Weed control will continue quarterly for years two
and three and twice a year thereafter.
Weeds will be killed or removed before they set seeds. Appropriate weed control
measures will be implemented under the direction of the habitat restoration specialist. A
list of exotic species anticipated on the site is presented in Table 9. In the event that
additional invasive species are encountered, the habitat restoration specialist shall refine
control measures to address the problem.
3. Protection Fence
The protection fences shall be inspected monthly for the duration of the project for
damage and openings during monitoring visits by the habitat restoration specialist.
Repeated vandalism or destmction of the protection fence shall be reported to the
property owner/project proponent and the habitat restoration specialist will provide
suggestions for remedial action.
4. Irrigation
Irrigation will be applied to container and salvaged plants at the discretion of the habitat
restoration specialist. Delivery techniques and schedules will vary depending on weather
conditions. Irrigation shall be applied to the wetland creation area using a sprinkler
system, while supplemental water shall be applied to the coastal sage scmb and native
grassland/thread-leaved brodiaea restoration using a water truck as directed by the habitat
restoration specialist. Timing of implementation is intended to utilize natural
precipitation, but amounts of rainfall are highly variable from year to year. All irrigation
shall cease at least one-year before requesting that the City and Wildlife Agencies sign-
off on the restoration.
C. Qualitative Monitoring
Evaluation of plant health and identifying and correcting problem areas is necessary for
ensuring successful vegetation establishment. Qualitative monitoring will be conducted in
each revegetation area weekly during implementation, and monthly for the first two years
(quarterly for the remainder of the project). The habitat restoration specialist will review
the revegetation areas to examine transplant vigor, native annual and grass germination,
and exotic plant encroachment. The biologist will document the findings and make
recommendations for remedial actions, if necessary.
A list of wildlife species observed in the restoration sites and interior open space lands
will be compiled during each qualitative monitoring visit. A description of wildlife use
will be included with each annual report (see below).
28
TABLE 9
ANTICIPATED EXOTIC SPECIES
CSS Riparian
Atriplex semibaccata
Australian saltbush
Bromus sp.
Brome grass
Cirsium vuigare
Bull thistle
Erodium sp.
Filaree, storksbill
Foeniculum vuigare
Sweet fennel
Hirschfeldia incana
Short-podded mustard
Nicotiana glauca
Tree tobacco
Ricinus communis
Castor bean
Arundo donax
Giant reed
Cirsium vuigare
Bull thistle
Cortaderia spp.
Pampas grass
Foeniculum vuigare
Sweet fennel
Nicotiana glauca
Tree tobacco
Ricinus communis
Castor bean
Schinus molle
Peravian pepper
Tamarix sp.
Tamarisk
D. Quantitative Monitoring
Quantitative monitoring will be performed to measure the development of vegetation in
the revegetation and enhancement areas and document achievement of success criteria in
the revegetation areas as defined by the performance standards. Different monitoring
techniques will be employed for each revegetation type.
1. Coastal Sage Scrub and Native Grassland
Survival rates of container stock and salvaged transplants will be determined four times
during the first year. Percent survivorship will be determined by making total counts of
live container plants and comparing that to the original number planted. Cover, diversity,
and density measurements will be sufficient to determine revegetation status for years 2-5
(see below).
Beginning in the second year, six permanent vegetation sampling stations will be
established inside both the Diegan coastal sage scmb and native grassland revegetation
sites to measure year-to-year changes in shrub cover, density, and diversity following the
protocol of the Califomia Native Plant Society (CNPS) Plant Communities Project
(Sawyer and Keeler-Wolf 1995) for a total of 12 sampling stations. Each sample endpoint
will be used as a photodocumentation point to record the progress of mitigation over the
monitoring period. This data will be compared to baseline data coUected from the intact
mature Diegan coastal sage scmb and native grassland habitat located within the
preserved open space on-site, unless an altemative off-site location is approved by the
Wildlife Agencies. Results will objectively determine if the revegetation areas approach
the conununity characteristics of the reference area habitat.
The CNPS sampling method is based on a 50-meter point transect centered on a
50-meter-by-5-meter plot. Sampling will be conducted in the spring on the mitigation
sites in order to record the maximum species diversity present.
2. Wetland Creation
Survival rates of container stock and salvaged transplants will be determined four times
during the first year and annually in subsequent years. The inventory taken at each of
these visits will include survivorship numbers for all transplanted species. Percent
survivorship will be determined by making total counts of live container plants and
comparing that figure to the original number planted.
Beginning in the second year, three permanent vegetation sampling stations will be
established inside the wetland creation area to measure year-to-year changes in shmb
cover, density, and diversity following the protocol of the CNPS Plant Communities
Project (Sawyer and Keeler-Wolf 1995). A plot will be established on each bank and one
30
down the center of the creation area. Each sample endpoint will be used as a
photodocumentation point to record the progress of mitigation over the monitoring
period. This data will be compared to baseline data collected from the intact mature
southem willow scmb habitat located within a 10-mile radius of the revegetation site.
Results will objectively determine if the revegetation and enhancement areas approach
the community characteristics of the reference area habitat.
3. Thread-Leaved Brodiaea
All thread-leaved brodiaea translocation plots and planting areas will be mapped using a
GPS unit with sub-mater accuracy. Individuals growing in these restoration areas will be
estimated three times between February and June and continue throughout the five-year
monitoring period. Total live plants and flowering individuals will be estimated and the
locations and full extent of the populations will be mapped and measured with a GPS
unit. Permanent photosampling points will be established at suitable locations. Weed and
native species growing in association with thread-leaved brodiaea will also be noted so
that they can be controlled. This data will also be collected in five control populations of
similar size and density in the preserved open-space each year.
E. Monitoring Reports
The habitat restoration specialist will submit annual reports summarizing monitoring
results to the CDFG, USFWS, USACE, RWQCB, and the City of Carlsbad on January 1
of each year. The quantitative monitoring section will include survey methods, data
summary analysis, performance standards comparison, discussion, reporting remedial
actions, recommendations, and photodocumentation. Each annual report will compare
findings of the current year with those in previous years.
F. Performance Standards
1. Coastal Sage Scrub, Native Grassland, and Wetland
Revegetation of the Fox Property revegetation areas will be considered successful when
the performance standards have been met. The performance standards defining species
diversity, density, and species dominance shall be based on values relative to a mature
native reference site. The reference sites will be located within the open space preserve
area on-site, to the extent possible. This should be possible for coastal sage scmb as a
mature community is present on the remaining slopes of Letterbox Canyon. The native
grassland on-site is small and scattered. If a suitable reference site is not available on-site,
a site will to be chosen from the open space in the vicinity. An off-site reference site will
be chosen for monitoring the created southem willow scmb, as this habitat is not
currently present on-site.
31
Performance standards for Diegan coastal sage scrub, native grassland, and wetlands are
presented in Tables 10, 11, and 12. For example, if a reference community had 60 percent
cover, the mitigation site must attain 80 percent relative cover by the end of five years, or
48 percent total cover. If these minimum levels for any one of these measurements are not
achieved (in any year), the habitat restoration specialist will recommend remedial actions
(such as replanting container stock) to reach the following year's expected levels. In order
to meet the performance standards, the habitat must sustain itself for a minimum of two
years in the absence of significant maintenance measures, which includes replanting,
irrigation, or eradication of weed infestations. It is anticipated that these measure will not
be required beyond Year 3, which would allow for the site to demonstrate sustainability
by the completion of Year 5. Other maintenance measures, such as regularly scheduled
weed control, may continue until the end of the project.
TABLE 10
FIVE-YEAR PERFORMANCE STANDARDS, AS A RELATIVE
PERCENTAGE OF REFERENCE AREA VALUES FOR DIEGAN COASTAL SAGE SCRUB
Year Transplant Survival
Coverage of
Shrabs and Herbs Diversity
1 90% --
2 -25% 50%
3 -40% . 70%
4 -60% 80%
5 -75% 80%
% = percent
TABLE 11
FIVE-YEAR PERFORMANCE STANDARDS, AS A RELATIVE
PERCENTAGE OF REFERENCE AREA VALUES FOR SOUTHERN WILLOW SCRUB
Year Transplant Survival
Coverage of
Shrabs and Herbs Diversity
1 100% --
2 80% 40% 50%
3 80% 75% 70%
4 80% 780% 80%
5 80% 90% 80%
% = percent
TABLE 12
FIVE-YEAR PERFORMANCE STANDARDS, AS A RELATIVE
PERCENTAGE OF REFERENCE AREA VALUES FOR NATIVE GRASSLAND
Year Coverage of Shrabs and Herbs Diversity
1 15% 40%
2 25% 50%
3 40% 70%
4 50% 80%
5 60% 80%
% = percent
32
2. Thread-Leaved Brodiaea
Success of the endangered plant translocation will be based on achieving a replacement
number of individuals that exceeds the number impacted by the constmction project. In
order to determine this, five thread-leaved brodiaea populations of similar size and
estimated density located in the preserved open-space will be selected as reference
populations. The total number of brodiaea individuals fiowering within each of these
populations will be counted every year. These flowering counts will be compared with the
number of individual flowering plants within each translocated soil patch and the
brodiaea restoration area. The site will be considered to be meeting success criteria if the
number of flowering individuals counted in the restoration population is within the range
of the reference population each of the five years. If flowering levels are proportionally
lower in the restoration area compared to the reference population, several factors that
may be contributing to unsuccessful recmitment will be analyzed (Skinner and Pavlik
1994). Factor analysis will include (but will not be limited to) examining pollinator
characteristics in the reserve population as compared to enhanced populations, weed
competition, and human impacts. All deleterious factors identified will be remedied to the
greatest extent possible to improve recmitment the following year.
3. Tolerance of Weeds
The cover of non-native annual grasses and herbs (such as brome grass or filaree), as
identified by the habitat restoration specialist, will be no more than 5 percent. There will
be 0 percent cover of species listed by the California Invasive Plant Council (Cal-IPC) list
of "Exotic Pest Plants of Greatest Ecological Concem", with the exception of brome
grasses on the revegetation sites (Cal-IPC 1999). By year five, no more than 5 percent of
the site shall consist of open ground.
4. Contingency Measures
If performance criteria are not achieved at the end of the fifth year, the permittee will
consult with the USFWS, CDFG, USACE, RWQCB, and the City of Carlsbad to
determine whether the mitigation effort is acceptable. The owner/project proponent
understands that failure of any significant portion of the mitigation area may result in a
requirement to replace or revegetate that portion of the site.
G. Notification of Completion
At the end of the fifth year, a final report will be submitted to the regulatory agencies
evaluating the success of the mitigation. The report will make a determination of whether
the requirements of the mitigation plan have been achieved.
33
At the conclusion of the five-year monitoring period, or at such time the project has
achieved the performance standards, the habitat restoration specialist shall inform the
owner/project proponent, USFWS, CDFG, USACE, RWQCB, and the City of Carlsbad.
A site review will be scheduled for all parties to review the revegetated sites. Upon
confirmation of project success, the regulatory agencies shall release the owner/project
proponent of all obligations.
H. Estimated Habitat Mitigation Costs
A cost estimate for each habitat replacement type is presented based on labor and
biological services (Table 13). Heavy equipment, installation of an irrigation system, and
fencing (and associated labor) costs were not included.
TABLE 13
HABITAT RESTORATION COST ESTIMATE'
Brodiaea"
Coastal
Sage Scrab'
Native
Grassland" Wetland"
Implementation (3 months)
Implementation $22,000 $30,000 $59,000 $5,000
Monitoring and Reporting $2,000 $1,500 $2,000 $500
Year 1
Maintenance $7,000 $18,000 $20,500 $3,000
Monitoring and Reporting $3,000 $1,500 $2,000 $1,000
Year 2
Maintenance $5,500 $10,000 $14,000 $1,500
Monitoring and Reporting $3,000 $1,000 $2,000 $500
Year 3
Maintenance $4,500 $6,000 $10,000 $1,000
Monitoring and Reporting $3,000 $1,000 $2,000 $500
Year 4
Maintenance $3,000 $5,000 $9,000 $1,000
Monitoring and Reporting $3,000 $1,000 $2,000 $500
Year 5
Maintenance $3,000 $4,000 $7,500 $1,000
Monitoring and Reporting $3,000 $1,000 $2,000 $500
TOTAL $62,000 $80,000 $132,000 $16,000
In 2005 dollars only, actual costs may vary.
2
Brodiaea restoration will include the 0.11-acre soil transfer within a 1.0-acre of non-native grassland converted to
valley needlegrass grassland; coastal sage scrub restoration will total 2.4 acres of revegetation on non-native
grassland and manufactured slopes; native grassland restoration will consist of the conversion of 3.7-acres of non-
native grassland to valley needlegrass grassland; wetland restoration will include the creation of a 0.3-acre southem
willow scrub.
34
References Cited
California Invasive Plant Council (Cal-IPC)
1999 Exotic Pest Plants of Greatest Ecological Concem in California.
http://www.cal-ipc.org/file_library/4898.pdf. October.
Holland, Robert F.
1986 Preliminary Descriptions of the Terrestrial Natural Communities of California.
Nongame-Heritage Program, Califomia Department of Fish and Game.
October.
Skinner, Mark, and Bmce Pavlik
1994 Inventory of Rare and Endangered Plants of Califomia. Califomia Native
Plant Society Special Publication No. 1, 5th ed. Sacramento.
RECON
2001 Revised Biological Technical Report for the Fox Property Project, Carlsbad,
Califomia. Prepared for Dean Miller. April 5.
2005 REVISED-Summary of Revisions to Biological Resources Impacts and
Proposed Mitigation for Fox-Miller Property. June.
Sawyer, J. O., and T. Keeler-Wolf
1995 A Manual of Califomia Vegetation. Califomia Native Plant Society.
Sacramento.
U.S. Department of Agriculture
1973 Soil Survey, San Diego Area, California. Soil Conservation Service and Forest
Service. Roy H. Bowman, ed. San Diego. December.
U.S. Fish and Wildlife Service (USFWS)
1998 Endangered and threatened wildlife and plants; determination of four
southwestem Califomia plants from vemal wetlands and clay soils. Federal
Register VoL 63, No. 197.
35