dudek, slender mariposa lily mitigation and monitoring...

Dudek, Slender Mariposa Lily Mitigation and Monitoring Plan,

Vista Canyon, Los Angeles County, California (June 2009)

J U N E

SLENDER MARIPOSA LILY MITIGATION AND MONITORING PLAN

for the VISTA CANYON PROJECT

Prepared for:

Impact Sciences, Inc. 803 Camarillo Springs Road, Suite A-1

Camarillo, California 93012

Prepared by:

605 Third Street

Encinitas, California 92024 Contact: Andy Thomson or Doug Gettinger

760.942.5147

JUNE 2009

Slender Mariposa Lily Mitigation and Monitoring Plan for the Vista Canyon Project

6115-06 i June 2009

TABLE OF CONTENTS

Section Page No.

1.0 INTRODUCTION AND PROJECT DESCRIPTION ...................................................1

2.0 DESCRIPTION OF THE MITIGATION PLAN ...........................................................1 2.1 Mitigation Plan Goals ............................................................................................. 1 2.2 Preliminary Schedule for Implementation .............................................................. 1 2.3 Time Frame for Success.......................................................................................... 2 2.4 Rationale for Expecting Success............................................................................. 2 2.5 Backup Contingency Measures............................................................................. 12

3.0 SALVAGE AREA AND RECEPTOR SITE DESCRIPTIONS..................................13 3.1 Slender Mariposa Lily Salvage Areas................................................................... 13 3.2 Slender Mariposa Lily Receptor Sites .................................................................. 13

4.0 IMPLEMENTATION PLAN .........................................................................................14 4.1 Site Preparation..................................................................................................... 14 4.2 Salvaging and Planting Slender Mariposa Lily .................................................... 14 4.3 As-Built Conditions .............................................................................................. 16

5.0 MAINTENANCE PLAN DURING 5-YEAR MONITORING PERIOD...................16

6.0 MONITORING PLAN DURING 5-YEAR PERIOD...................................................19 6.1 Receptor Site Monitoring Methods and Schedule ................................................ 19 6.2 Annual Reports ..................................................................................................... 21

7.0 COMPLETION OF MITIGATION AND PERFORMANCE CRITERIA..................22

8.0 LITERATURE CITED ...................................................................................................23

APPENDIX

A Soil Test Results


TABLE OF CONTENTS (CONT.)

6115-06 ii June 2009

Page No.

LIST OF FIGURES

1 Regional Map...................................................................................................................... 3 2 Vicinity Map ....................................................................................................................... 5 3 Development Plan and Project Impacts .............................................................................. 7 4 Salvage and Receptor Site Location ................................................................................... 9

LIST OF TABLES

1 Implementation Schedule.................................................................................................... 2 2 Receptor Site Monitoring Schedule .................................................................................. 19 3 Performance Criteria – Slender Mariposa Lily Mitigation Plan....................................... 22


6115-06 1 June 2009

1.0 INTRODUCTION AND PROJECT DESCRIPTION

This Slender Mariposa Lily Mitigation and Monitoring Plan (Mitigation Plan) outlines implementation guidelines for the salvage, relocation, maintenance, and monitoring of slender mariposa lily (Calochortus clavatus var. gracilis) from areas that will be impacted by implementation of the proposed Vista Canyon Project. The Vista Canyon project area encompasses approximately 185 acres, located south and east of State Route 14 (SR-14), north of Lost Canyon Road and west of Sand Canyon Road in unincorporated Los Angeles County, California, directly adjacent to the City of Santa Clarita (City) (Figures 1–2) (Thomas Guide map page 4552, map grid B-3). The project area is proposed for annexation to the City, and the City will serve as the lead agency for the proposed project. SR-14 forms the northern boundary of the project area and provides the bulk of regional access to the area via the Interstate 5 (I-5)/SR-14 interchange. The project area is surrounded by existing development (Figure 2). The Santa Clara River bisects the project area from east to west.

The project applicant, Vista Canyon Ranch, LLC (Vista), is proposing to develop the project area with a mixed-use development consisting of up to 1,350 residential units and up to 950,000 square feet of commercial floor area.

Implementation of the proposed project will impact a small knoll containing slender mariposa lily. Proposed mitigation for direct impacts to slender mariposa lily will include a combination of bulb and seed salvage. The Mitigation Plan proposes salvage and translocation of bulbs and seed from within the disturbance area (Figure 3) to an appropriate receptor site within the Vista Canyon property where they can be preserved in perpetuity (Figure 4). A compensation ratio of 1:1 is recommended by the California Department of Fish and Game (CDFG).

2.0 DESCRIPTION OF THE MITIGATION PLAN

2.1 Mitigation Plan Goals

The Mitigation Plan outlined herein is focused on mitigating for impacts to the on-site population of slender mariposa lily that occurs within the development footprint of the proposed project. The goal of the Mitigation Plan is to successfully reestablish slender mariposa lily plants at an appropriate/compatible on-site receptor site, where the plants can successfully exist and can be afforded protection in perpetuity.

2.2 Preliminary Schedule for Implementation

The Mitigation Plan includes a combination of seed collection and bulb salvage. Timing of the seed collection and bulb salvaging will be determined based upon seasonal weather constraints


6115-06 2 June 2009

and timing of scheduled project grading. Seed collection will be timed to occur when seeds are mature, but before seed has dehisced from seed capsules (usually in May–June). Harvesting of slender mariposa lily bulbs should occur when the plants are dormant (summer and fall), ideally just before the onset of the rainy season (late fall or early winter). Planting work (both seeds and bulbs) for the Mitigation Plan is anticipated to occur in the fall or early winter (October–December). Table 1 shows the anticipated sequence for implementation:

Table 1 Implementation Schedule

Mitigation Activity Approximate Activity Sequence Flagging existing lily plants in development areas Spring – during blooming period Seed collection Early summer – when seeds are mature Bulb excavation Fall – prior to onset of rainy season Receptor site preparation and installation of bulbs and seed Fall or early winter 5-year maintenance and monitoring period Years 1–5

2.3 Time Frame for Success

The time frame to document project success is during the 5-year maintenance and monitoring period. Project success is defined as the ability of the planted slender mariposa lily to persist during the monitoring period. The target number of slender mariposa lily survival is at least the quantity that was estimated as being impacted by the proposed project. Measurement of project success will be determined in years 3, 4, or 5 after the seeds and bulbs have had an opportunity to become established.

2.4 Rationale for Expecting Success

As previously described, the proposed slender mariposa lily receptor site will be located on site in an area that contains similar vegetation types and topographic features to the salvage area. The proposed receptor site is approximately 0.25 mile from the salvage area.

Santa Clarita

Lancaster

Palmdale

Valencia

San Fernando

PasadenaBurbank

Hollywood

El Monte

Azusa

Pomona

Walnut

Whittier

Lakewood

Bell

Los Angeles

SantaMonica

RanchoPalos Verdes

LongBeach

Malibu

Reseda

RIVERSIDE COUNTY

ORANGE COUNTY

LOS

ANG

ELES

CO

UN

TYSA

N B

ERN

ARDI

NO

CO

UN

TY

KERN COUNTY

LOS ANGELES COUNTY

LOS ANG

ELES COUNTY

VENTURA COUNTY

P A C I F I C O

CE

AN

Project Site

FIGUREVista Canyon Slender Mariposa Lily Mitigation and Monitoring PlanRegional Map 1

0 11Miles

Z:\P

roje

cts\

j611

506\

MA

PD

OC

\WO

RK

ING

\Fig

1_R

egio

nal.m

xd


6115-06 4 June 2009

INTENTIONALLY LEFT BLANK

0 2,000 4,000Feet

Project Site

Source: USGS Topo 7.5 Minute Series - Mint Canyon Quadrangle

Vista Canyon Slender Mariposa Lily Mitigation and Monitoring Plan2

FIGURE

Vicinity Map

Z:\P

roje

cts\

j611

506\

MA

PD

OC

\WO

RK

ING

\Fig

2_V

icin

ity.m

xd


6115-06 6 June 2009

INTENTIONALLY LEFT BLANK

FIGURE

IMAGE SOURCE: Digital Globe, 2007

Vista Canyon Slender Mariposa Lily Mitigation and Monitoring PlanDevelopment Plan and Project Impacts 3

0 500Feet

Z:\P

roje

cts\

j611

506\

MA

PD

OC

\WO

RK

ING

\Fig

3_D

evP

lan_

Pro

ject

Impa

cts.

mxd

Slender Mariposa Lily Impact SiteProject AreaProposed Site Plan

FIGURE

IMAGE SOURCE: Digital Globe, 2007VEGETATION SOURCE: Impact Sciences, 2009

Vista Canyon Slender Mariposa Lily Mitigation and Monitoring PlanSalvage and Receptor Site Location 4

0 500Feet

Slender Mariposa Lily Receptor Site

Slender Mariposa Lily Salvage Site

Project AreaVegetation Communities:

Active floodplain (braided channels with mixed riparian and alluvial scrub)

Alkali rye series

Alkali rye series (elderberry)

Big sagebrush - buckwheat series

California sagebrush - buckwheat series

Chamise series

Coast live oak series

Cottonwood series

Disturbed

Elderberry series

Mixed native and non-native

Mulefat series

Non-native herbaceous series

Sagebrush series

Saltbush series

Saltgrass series

Yerba santa series

Z:\P

roje

cts\

j611

506\

MAP

DO

C\W

OR

KIN

G\F

ig3_

Sal

vage

_Rec

epto

r_S

ite.m

xd


6115-06 11 June 2009

The receptor site is located in chamise (Adenostoma fasciculatum)-dominated habitat, which currently supports splendid mariposa lily (Calochortus splendens) (Forde and Read 2008). Co-dominant plant species at this location include California sagebrush (Artemisia californica), California buckwheat (Eriogonum fasciculatum), and buck brush (Ceanothus cuneatus). The salvage area also supports California sagebrush and California buckwheat as dominant plant species, and was mapped as California sagebrush-buckwheat series (Forde and Read 2008).

Soils at the salvage area are Saugus loam, 15%–30% slopes (ScE) (Woodruff et al. 1970). Soils at the receptor site are Ojai loam, 2%–9% slopes (OgC) and Terrace escarpments (TsF) (Woodruff et al. 1970). The soil types at the salvage area and the receptor site are similar in that they are well-drained and formed from weakly consolidated sediment. Based on site-specific composite soil samples collected from the salvage area and the receptor site, soils at both locations are also similar in terms of soil texture (both were classified as sandy loam) and most constituent major and micronutrients (Appendix A). One noted difference in the soil texture is that the soil at the receptor site was described as hydrophopic, whereas the soil at the salvage area was not. While there are some minor differences between the soil type, texture, and chemistry between the salvage site and the receptor site, this Mitigation Plan proposes soil salvage from the areas currently supporting slender mariposa lily and placement at the receptor site, which minimizes the significance of the apparent discrepancies.

Elevations at the salvage area range from between approximately 1,485 feet above mean sea level (AMSL) to 1,560 feet AMSL. Similarly, elevation at the receptor site ranges from between approximately 1,520 feet AMSL to 1,550 feet AMSL. Slope exposures are similar, with a north- to northeast-facing aspect at the salvage areas and a north- to northwest-facing aspect at the receptor site.

The close proximity of the proposed receptor site to the salvage site along with similar soils, elevation, and slope exposure will help ensure that the introduced individuals experience similar environmental conditions in which the natural population presently exists. The physical and chemical similarities of the sites increase the probability for success.

In addition to careful site selection as described above, Dudek’s previous work with salvaging, transplanting, and establishing Calochortus (both Calochortus clavatus var. gracilis and Calochortus plummerae) at another project in Santa Clarita (Newhall Land's RiverVillage Project), indicates that successful results can be achieved at the Vista Canyon site by following procedures developed for that project. In the autumn of 2005, seed and bulbs were salvaged from the RiverVillage development footprint and planted at a preserve area into selected sites in similar habitat in late 2005 and early 2006. Despite 2 successive years of drought following transplantation, results of the first 3 years showed a success rate of 69% in spring 2006, 34% in


6115-06 12 June 2009

spring 2007, and 93% in spring 2008 (Dudek 2007a, 2007b; Thomson 2008). By comparison, almost no naturally occurring Calochortus in the nearby reference population were observed in spring 2006, none were observed in spring 2007, and approximately 75% of known individuals were observed flowering in spring 2008. The quantity of transplanted individuals observed each year has generally corresponded with rainfall amounts, with lower numbers observed in low rainfall years, and higher numbers observed in higher rainfall years. In addition to the success rate for transplanted bulbs, successful seeding efforts were documented. Each year for the first 3 years of the program, persisting juveniles from the seeding efforts were documented. Some of this success is attributable to adaptive management measures, wherein during extreme drought conditions in the first and second years, some supplemental hand-watering of the plots occurred. Measures found successful at the RiverVillage project will be implemented at the Vista Canyon project.

2.5 Backup Contingency Measures

The Mitigation Plan utilizes an adaptive management approach, wherein corrective measures will be implemented during the 5-year monitoring period if problems affecting the survival and/or successful establishment of slender mariposa lily are detected. For example, if during the 5-year monitoring period, rainfall is significantly below average during the growing season for slender mariposa lily (as determined by the Project Biologist), supplemental water may be supplied to the receptor sites in order to help sustain the population and mimic average rainfall conditions.

As an additional backup contingency measure, a portion of the slender mariposa lily seed collected from source populations (impact areas) will be reserved and used to supplement plants at the receptor sites if necessary. Viability of slender mariposa seed is for a relatively short period when stored at room temperature. The viability of stored seed can be significantly lengthened by storage at freezing temperatures. Therefore, the back-up seed will be stored in appropriate conditions at freezing temperatures until it is either utilized for planting as a back-up contingency measure, or if the project appears successful, added to the receptor site to increase the quantity of plants.

Additional backup contingency measures may be implemented as unforeseen issues arise that could potentially affect the success of the Mitigation Plan.


6115-06 13 June 2009

3.0 SALVAGE AREA AND RECEPTOR SITE DESCRIPTIONS

3.1 Slender Mariposa Lily Salvage Areas

During surveys for special-status plants conducted in March, April, and May 2008, slender mariposa lily individuals were found on site and mapped (Forde and Read 2008), with approximately 150 individual slender mariposa lily plants identified. Site visits by Dudek during February 2009 confirmed the slender mariposa lily population and observed approximately 200 slender mariposa lily individuals on site. The number of individuals of this species detected varies every year due to natural population phenology (i.e., natural population increase and decrease cycles and their reliance on rainfall to bloom).

The location where slender mariposa lily occurs is on the slopes of a small hill on the southern-central portion of the project site within the impact footprint of the proposed development (Figure 3). The area where slender mariposa lily is known to occur within the impact footprint is considered the salvage area.

3.2 Slender Mariposa Lily Receptor Sites

Two potential receptor sites located within the project site were evaluated for suitable conditions. Based on the selection criteria described in Section 2.4, one of the sites is more favorable than the other. This site has been designated the receptor site. The alternate site, which is located approximately 600 feet east of the salvage area in the southeastern portion of the project site just north of the railroad tracks, was not selected based on the density of existing brushy habitat, the dominance of Great Basin sagebrush (Artemisia tridentata), and lack of adequate area for planting.

The selected receptor site is located north of the Santa Clara River, and just south of SR-14 (Figure 4). As described earlier, the receptor site is located in mapped chamise series habitat, with chamise, California buckwheat, California sagebrush, and buck brush as the dominant shrub species. The shrub canopy is relatively open, with gaps between shrubs that are large enough to prepare planting plots. The herbaceous layer is relatively diverse and includes common tarplant (Deinandra fasciculata), lomatium (Lomatium utriculatum), and splendid mariposa lily (Forde and Read 2008).

Specific planting locations for transplanted Calochortus bulbs will be determined in the field by the Project Biologist. The receptor site will be marked with stakes and the location recorded by a global positioning system (GPS) in the field to facilitate relocation during the monitoring period. The receptor sites will be protected and situated in designated open space.


6115-06 14 June 2009

4.0 IMPLEMENTATION PLAN

The implementation of the Mitigation Plan shall be accomplished by an experienced, qualified, native landscape contractor (Contractor) and monitored by the Project Biologist. All stages of the Implementation Plan, from site preparation to installation completion and seeding, shall be overseen by the Project Biologist, who shall ensure that the Mitigation Plan is appropriately executed.

4.1 Site Preparation

Site preparation for the Mitigation Plan will begin in the spring of the planting year. Site preparation activities are detailed below.

• Individual slender mariposa lily plants will be marked in the field during the blooming period in the spring prior to the year of planting, which is estimated to be during April and/or May (but may be done earlier or later depending on floral development). At the salvage areas, individual slender mariposa lily locations will be marked with a pin flag.

• If site grading is ongoing at the time, the salvage area will be marked in the field and fenced with temporary construction fencing until the slender mariposa lily plants can be removed from the site.

• Planting plots will be designated at the receptor sites. The Project Biologist will determine appropriate planting locations within the receptor sites based on biological conditions important to the survival of the planted individuals (e.g., soils, slope, and aspect). The plots will be established within small openings in the shrub canopy at the receptor site.

• Any non-native plant species that are potentially invasive and/or pose a threat to the establishment, development, or persistence of slender mariposa lily will be controlled prior to planting.

• All equipment maintenance, staging, dispensing of fuel or oil, or any other such activities will occur in designated upland areas.

4.2 Salvaging and Planting Slender Mariposa Lily

The following general methods are proposed for the salvaging and transplantation of slender mariposa lily:

• Prior to salvaging the slender mariposa lily bulbs at the salvage areas, seeds will be collected from flagged individuals once the seed has matured, but prior to the seed


6115-06 15 June 2009

capsules opening to disperse the seed. Seed will be stored in breathable paper bags in a cool, dry, and dark place until planted at the receptor site. After seeds are completely dried out, the seed will be stored in the freezer to extend the length of seed viability. A portion (approximately 10%) will be retained as a back-up contingency measure.

• Slender mariposa lily bulbs will be salvaged from known locations within the project limits of grading. A small digging spade or shovel will be used to salvage bulbs, depending on access constraints and the number of individuals at each particular location.

• An attempt will be made during bulb salvage to collect the bulbs with their surrounding soil and associated biomass intact. Due to the soil type found on site, the soil may not stay consolidated as a solid mass. If soil masses will not stay consolidated, the bulbs will be collected separate from the soil and stored in appropriate storage conditions (cool, dark, and dry location) until planted at the receptor site.

• The soil from areas where slender mariposa lily bulbs were abundant will be salvaged. The top 8–12 inches of soil will be removed and then used at the planting locations within the receptor sites.

• If slender mariposa lily bulbs, or any other native bulbs, are detected during the excavation of receptor sites or in disturbed soils within the salvage areas, they will be planted at the receptor sites at the appropriate soil depth during the transplantation process.

• Salvaged bulbs will be planted at the receptor site in plots. The plots may be various sizes, but a typical planting plot will measure approximately 2 feet by 2 feet with nine salvaged bulbs planted in each plot. Planted bulbs will typically be arranged in a grid pattern to facilitate biological monitoring; however, alternative configurations may be used, as appropriate. Detailed notes about planting locations will be kept by the Project Biologist to enable follow-up monitoring. The plots will be distributed in natural openings in the habitat at the receptor site.

• Bulbs will be planted at a depth of approximately 2–6 inches (depending on the size of the bulb). Smaller bulbs will be planted shallower and larger bulbs will be planted deeper. Bulbs will be oriented correctly (roots down, stem up) in the soil during planting.

• In addition to bulb salvage and transplantation, a portion of the collected slender mariposa seed will be planted in plots within the receptor sites. The plots will be similar in size as those described for the bulbs. Seeded areas will be prepared by removing all weedy debris, scarifying the soil to approximately 1 inch in depth and sowing the seed at 0.25–0.50 inch in depth. The soil scarification will be done by shovel, and/or rake, and the seeding will be done by hand.


6115-06 16 June 2009

• Herbivore-exclusion fencing will be installed surrounding planting plots or groups of planting plots to prevent plant herbivory. Herbivore-exclusion fencing will be constructed of poultry netting (or similar) and will be installed at least 18 inches below ground surface and will extend to approximately 30 inches above ground level. Herbivore-exclusion fencing may also be installed to cover the top of each plot.

• Markers will be installed and maintained at each plot at the slender mariposa lily receptor site locations to identify the planted slender mariposa lily locations during the 5-year long-term maintenance and monitoring period. The markers may consist of 2-inch by 2-inch by 24-inch wooden survey hub stakes, or equivalent, driven into the ground next to each plot. The plot locations will also be recorded with a GPS after planting to facilitate relocating the plots for monitoring and reporting in subsequent years.

• Receptor sites will be watered-in to prevent the formation of cracks and air pockets in the soil. Approximately 1 week after the initial planting period, additional native soil will be spread to fill in gaps or depressions if they form after the soil has settled, and the area will be watered in a second time.

• If seasonal rains are inadequate to keep the soils moist through the first growing season, supplemental irrigation may be supplied to the receptor sites as determined by the Project Biologist. Supplemental irrigation will be conducted on an as-needed basis approximately every 2 to 4 weeks during the initial growing season, depending on rainfall, temperatures, and day length.

4.3 As-Built Conditions

The GPS locations of each plot within the receptor area will be overlaid on an aerial image of the site to document the final plot layouts. The City and CDFG will receive copies of this plot map as part of the initial completion report. The plot map will also serve as a record that will be used for reporting and management purposes during long-term biological monitoring.

5.0 MAINTENANCE PLAN DURING 5-YEAR MONITORING PERIOD

The primary effort of the maintenance plan will be concentrated in the first season of growth to help offset the negative effects of site disturbance and non-native weed competition at the slender mariposa lily receptor sites. Subsequent seasons should require less intensive maintenance as the vegetation reaches a state of equilibrium, but persistent weed control of invasive exotic weeds will likely be required. Maintenance issues are described in more detail below.


6115-06 17 June 2009

Pest Control

Weeds are expected to be the primary pest problem in the slender mariposa lily receptor sites. Weed control should be conducted on a regular basis during the long-term maintenance and monitoring period. Maintenance should be conducted monthly during the growing season (November–May) of the first year and four times annually thereafter until the end of the 5-year maintenance and monitoring period. Weed growth and prevalence will be assessed by the biological monitor and remedial weeding will be directed and completed as necessary based on seasonal conditions.

Target non-native species selected for control in this plan include those non-native plant species that are potentially invasive and/or pose a threat to the establishment, development, or persistence of slender mariposa lily. The primary target species will be those identified and listed by the California Invasive Plant Council in the California Invasive Plant Inventory, which is available online (Cal-IPC 2006).

A combination of physical removal and herbicide treatment will likely be required to control invasive species. The method of weed control will be based on the most effective method for the species being targeted and the stage of plant development. Properly timed, repeat herbicide applications are usually required for complete control of most invasive perennial species. Refer to the herbicide label for information on proper timing and application rates. All applicable laws, regulations, safety precautions, and label directions must be followed when performing pest control. The Contractor performing the work should consult a licensed Pest Control Adviser if specific pest control recommendations are required. All weed debris should be removed from the mitigation area and disposed of in a legal manner.

Invertebrate pests and diseases are not expected to be a problem in the slender mariposa lily receptor sites. Vertebrate pests such as gophers, ground squirrels, rabbits, rats, voles, etc. are being addressed by installation of exclusion fencing around each receptor site at the time of project implementation. The Project Biologist and the Contractor shall monitor the exclusion fencing for effectiveness and take appropriate remedial measures should it become necessary. All applicable laws, regulations, safety precautions, and label directions shall be followed when performing pest control.

Fencing

Herbivore-exclusion fencing will remain in place, and repaired as necessary, to effectively protect the slender mariposa lily from browsing as well as act as a deterrent to inadvertent trampling.


6115-06 18 June 2009

Seeding

Supplemental seeding may be recommended by the Project Biologist to prevent potential erosion and to encourage native species establishment. If seeding is recommended, an appropriate native seed mix will be specified by the Project Biologist, and may include the following proposed plant species:

• California buckwheat (Eriogonum fasciculatum)

• California everlasting (Gnaphalium californica)

• California poppy (Eschscholzia californica)

• California sagebrush (Artemisia californica)

• Common goldfields (Lasthenia californica)

• Deerweed (Lotus scoparius)

• Foothill needlegrass (Nassella lepida)

• Miniature lupine (Lupinus bicolor)

• Purple needlegrass (Nassella pulchra)

• Rancher’s fireweed (Amsinckia menziesii var. menziesii)

• Sacapellote (Acourtia microcephala)

• Tarplant (Deinandra fasciculata)

• Tidy-tips (Layia platyglossa).

Trash and Debris

Trash and debris will be removed from the site on a regular basis during maintenance visits.

Erosion Control

The site will be monitored for erosion problems, and measures will be taken, as necessary, to help prevent erosion within plot locations and seeded areas.

Access Control

The receptor sites will be checked regularly during scheduled maintenance visits for evidence of human disturbance, including off-road vehicle use, illegal dumping, vandalism, pedestrian access, and unauthorized brush clearing.


6115-06 19 June 2009

Supplemental Irrigation

The soils at the receptor sites will be monitored for moisture during the growing season. If soil moisture levels appear inadequate to support slender mariposa lily during the growing period, particularly during the first 2 years of the 5-year maintenance and monitoring period, supplemental irrigation may be supplied to the planted slender mariposa lily plants if recommended by the Project Biologist.

6.0 MONITORING PLAN DURING 5-YEAR PERIOD

Biological monitoring of the planted slender mariposa lily plants during the 5-year maintenance and monitoring period will measure the establishment of the slender mariposa lily and evidence of species health and proliferation. Field-collected data will provide a quantitative measure of the survival and establishment of the slender mariposa lily and flowering/seed production each year. Monitoring will likely rely on observations of flowering individuals, which are easier to locate and identify than non-flowering individuals. However, because the flowering of this species is so variable from year-to-year, monitoring will also include observations of vegetative growth (leafing out). Monitoring will occur in the winter and spring of each year during the growing season and while the slender mariposa lily is in bloom. Additional monitoring at the site may occur periodically throughout the year to determine the need for maintenance to protect the planted slender mariposa lily plants from weed invasion or other disturbances.

6.1 Receptor Site Monitoring Methods and Schedule

Biological monitoring will be conducted by the Project Biologist to determine the status of the slender mariposa lily plants (through periodic monitoring and collection of quantitative data) and the need for any remedial measures. This work will include a quantitative biological assessment each year, to be timed during the growing season and with the flowering of slender mariposa lily and qualitative assessments to assess overall site conditions and maintenance activities (Table 2).

Table 2 Receptor Site Monitoring Schedule

Status/Completed Year 0 Year 1 Year 2 Year 3 Year 4 Year 5

Quarter Quarter Quarter Quarter Quarter Quarter Phase Task Description 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4

Flag existing slender mariposa lily plants

X Salvaging and Transplantation

Collect slender mariposa lily seed

X X

Slender Mariposa Lily Mitigation and Monitoring Plan for the Vista Canyon Project Area

Table 2 (Continued)

6115-06 20 June 2009

Status/Completed Year 0 Year 1 Year 2 Year 3 Year 4 Year 5

Quarter Quarter Quarter Quarter Quarter Quarter Phase Task Description 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4

Salvage slender mariposa lily bulbs

X

Transplant slender mariposa lily bulbs

X

Install protective fencing X Prepare final map and installation completion report

X

Maintenance Weed control – Monthly during growing season of the first year, four times per year thereafter

X X X X X X X X X X X X X X X X X X X X X

Monitoring Biological monitoring/data collection

X X X X X X X X X X X

Site Protection Verify fencing and make repairs

X X X X X X X X X X X X X X X X X X X X X

Reporting Prepare year-end reports X X X X X Remedial Measures To be determined each

year and at end of monitoring period

X X X X X

Final Sign-Off* City and CDFG to verify site conditions

X

* The actual date/timing for final sign-off by the City will be based upon actual achievement of success criteria.

The purposes of the monitoring visits will be to document weed problems, site security and maintenance issues, and the growth, flowering, and seed production of slender mariposa lily within the receptor sites. At each monitoring visit, the following measurements and observations will be made, as applicable.

• Observation of evidence of vegetative growth. Floral structures are needed to conclusively verify that the presumed vegetative growth in fact is slender mariposa lily. However, experienced biologists can often identify mariposa lily in general from vegetative growth only, particularly if the individual planting locations are known. Observation of vegetative growth is better accomplished in the winter or early spring, before leaf shoots begin to senesce. After successive years of monitoring, and with knowledge of the known locations of planted slender mariposa lily, it will be possible to estimate the number of individuals present by examining vegetative growth.


6115-06 21 June 2009

• Observation of flowering and seed production. All flowering individuals observed within the receptor areas will be counted. Biological monitoring during the blooming period may require multiple visits because there is often an extended blooming period (several weeks) during which time flowering is staggered (i.e., some individuals may have open flowers and be easily detected, while other individuals may have closed flowers or flowers in bud and go undetected). Additionally, the peak blooming period varies from year to year; therefore, multiple visits will aid in capturing a more accurate estimate of flowering individuals. All flowering individuals detected during the monitoring periods will be recorded on data sheets.

• Reference Site Monitoring. In addition to monitoring the planted slender mariposa lily, reference site monitoring will be conducted at a nearby undisturbed slender mariposa lily population. A fixed area (reference site) will be demarcated, wherein all flowering individuals detected will be counted during the annual data collection period to provide comparison data. This will provide consistent, year-to-year data on a discrete portion of the existing population, which will be useful for statistical purposes.

• Photo-documentation. Representative photographs will be taken from fixed points within the receptor sites as well as the reference site, including overall and close-up views, from fixed viewpoints, and from representative plots, allowing year-by-year comparison during the monitoring period.

• Monitor soil moisture and rainfall patterns. Rainfall patterns and weather forecasts will be researched and soil moisture levels on site will be evaluated to determine if supplemental irrigation is necessary. If it is determined that precipitation during the growing period has been inadequate to support the planted slender mariposa lily, particularly during the first 2 years of the 5-year maintenance and monitoring period, supplemental irrigation may be recommended, as determined by the Project Biologist.

• General preserve monitoring. Observations will be made of the general status of fencing, signage, perimeter control (trespass), erosion control, litter, and pest species.

6.2 Annual Reports

An annual monitoring report will be prepared in the fall/winter of each year of the 5-year maintenance and monitoring period, summarizing the information collected during the yearly site visits. Data will be summarized in tabular format where feasible. Each annual report will present the monitoring methods and a description of the current conditions of the receptor site, and will provide copies of field maps and data sheets, representative photographs, monitoring results, regional precipitation measurements for the year, an analysis of success and/or failure for all


6115-06 22 June 2009

portions of the project, and recommendations for future maintenance and possible remedial measures or contingency plans, if necessary.

A discussion of any existing or future potential impacts to the planted slender mariposa lily that are known to the Project Biologist or that may occur as a result of human activities and environmental conditions also will be included. A status report will be provided to the City and CDFG by the end of each calendar year during the maintenance and monitoring period. A final, end-of-the-project monitoring report will be filed with the City and CDFG upon achievement of success criteria and final acceptance will be considered at that time.

7.0 COMPLETION OF MITIGATION AND PERFORMANCE CRITERIA

At the end of each year, the Project Biologist will inform Vista, the City, and CDFG of the progress of the plan. When the long-term maintenance and monitoring period is complete, or sooner if the success criteria are achieved early, the City will be invited to review the conditions of the receptor sites and document the status of the planted slender mariposa lily. Final performance criteria are included in Table 3.

Table 3 Performance Criteria – Slender Mariposa Lily Mitigation Plan

Feature Criteria Monitoring Frequency Findings Action

Slender mariposa lily seed collection

Collect seed for use at receptor sites and for back-up contingency.

Ongoing monitoring of seed collection activities

Quantity of seed collected is of an adequate amount for seeding at receptor sites and for back-up contingency storage.

Monitor timing of seed maturation so seed is collected when mature, but prior to dispersal. Ensure proper seed storage conditions.

Slender mariposa lily seeding

Apply seed in appropriate locations as described in plan.

Spring of each year (December–March for vegetative growth; April–May if flowering)

Demonstrated ability to persist at the receptor site by exhibiting evidence of vegetative growth and/or flowering.

Monitor seedling success during regularly scheduled monitoring visits. Report results in annual monitoring reports.

Slender mariposa lily bulb salvaging

Salvage slender mariposa lily individuals from within the project limits of grading.

Ongoing monitoring of salvaging operations

Estimate total number of individuals salvaged.

Ensure proper storage of salvaged bulbs until they can be planted at receptor sites.

Slender mariposa lily transplantation

Transplant salvaged bulbs and associated soil.

Ongoing monitoring and verification of work

Notify City and CDFG of number salvaged and planted.

Install all bulbs at the predetermined receptor locations according to this plan.

Slender mariposa lily survival (bulbs

A minimum 1:1 ratio of the quantity of individuals

Spring of each year (April–May)

Demonstrated ability to persist at the

If successful, program complete. If not,

Slender Mariposa Lily Mitigation and Monitoring Plan for Vista Canyon

Table 3 (Continued)

6115-06 23 June 2009

Feature Criteria Monitoring Frequency Findings Action

and seeds) impacted producing vegetative growth during any of the last 3 years over the 5-year monitoring period.

receptor site by exhibiting evidence of vegetative growth and/or flowering.

remedial measures or additional maintenance and monitoring are to be implemented, if required.

Maintenance, weed control, verification of fencing/protection, and monitoring of herbivory

Remove invasive weeds from around and within slender mariposa lily receptor sites. Invasive perennial weeds not to exceed 5% cover at any time during the maintenance and monitoring period. Keep herbivore-exclusion fencing in place and functional. Check for rodent problems.

Monthly during the first-year growing period, quarterly thereafter until the end of the 5-year long-term maintenance and monitoring program

Verify weed maintenance and site protection. Assess herbivory on slender mariposa lily subpopulations.

Take remedial measures and/or make repairs as needed. Control invasive weed species throughout entire 5-year program.

An adaptive management approach has been established in this plan and will be utilized for the 5-year maintenance and monitoring period, wherein backup contingency measures (such as providing supplemental water or supplemental seeding) will be initiated if it appears as though the plan may not meet the established success criteria. In the unlikely event that the plan has failed to sustain the planted slender mariposa lily during the 5-year maintenance and monitoring period, the City will be consulted to determine contingency measures to be implemented to compensate for the failure of the plan, if required.

8.0 LITERATURE CITED

California Invasive Plant Council (Cal-IPC). 2006. California Invasive Plant Inventory. Cal-IPC Publication 2006-02, California Invasive Plant Council: Berkeley, California. http://www.cal-ipc.org/ip/inventory/pdf/Inventory2006.pdf

Forde, A.M., and E. Read. 2008. Biological Assessment Vista Canyon Ranch Los Angeles County, California. Prepared for Vista Canyon Ranch L.L.C. and The River Project. August 27.

Woodruff, G.A., W.J. McCoy, and W.B. Sheldon. 1970. Soil Survey Antelope Valley Area California. U.S. Department of Agriculture, Soil Conservation Service, Washington


6115-06 24 June 2009

D.C., in cooperation with the University of California Agricultural Experiment Station, Davis, California.

APPENDIX A Soil Test Results

dudek, slender mariposa lily mitigation and monitoring...

Documents