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HomeMy WebLinkAboutCT 99-08; Spyglass II; Tentative Map (CT) (35)JUN 22 '00 07:14PM 619 f*" 5380 —* P.1/5 Perennial Grassland Revegetation Plan Spyglass Development Mitigation Carlsbad, California PSBS#T472B UTM: 3.669,OOOraN, 473,OOOmE x Prepared for Concordia Homes of California, LLC 7130 Avenida Encinas, Suite 200 Carlsbad CA 92009^657 and Ladwig Design Group, Inc. 703 Palomar Airport Road, Suite 300 Carlsbad CA 92009 Prepared by Pacific Southwest Biological Services. Inc. Post Office Box 985 National City CA 91951-0985 Telephone 619 477 5333 Facsimile 61.9 477 5380 E-roajl: bio@psbs.com 22 June 2000 R. Mitchel Beauchamp, M. Sc., President cr RECEIVED JUN 2 2 2181 LADWIG DESIGN GR Received: 8/22/OO 8:27PM; 819 477 538O -> WILSON ENGINEERING; Page 2 . JUN 22 '00 07:15PM 619/"""7 5380 ''^ P. 2/5 Perennial Grassland Revegetation Plan Spyglass Development Mitigation Carlsbad, California Introduction The proposed development of an undeveloped sile at tlie southeast corner of El Carnino Real and Carlsbad Village Drive (Elm Street), called Spyglass II (CT 99-08/SDP 99-04.SUP 99-04/ HDP 99-07) involves impacting a remnant Perennial Grassland by landform alteration of the sile. As mitigation for mis impact, the establishment of a 10.3- acre area of perennial grassland is required to fulfill Condition 5 of the Mitigating Measures for the .Spyglass (I project. This Plan details the procedures 10 establish that habitat in an area formerly involved with agricultural use and now covered by weedy, non-native grasses and Ibrbs. The site is a portion of land owned by the State of California and administered by the Department of Transportation as a mitigation bank. The site lies northwest of another area proposed as a mitigation area, called Holly Springs. The site is suitable For restoration to Perennial Grassland by virtue of the Altamont clay soils on the site and the proposed land uses nearby. The site lies between SO and 200 feet in elevation and is generally a west to northwest facing slope system. The lands to the south are owned by the Carlsbad Unified School District and presumable will be developed as a school site. Having a natural preserve next to an educational facility offers opportunities for educational and monitoring activities. Methodology The following steps are planned to result in the establishment and maintenance of a native, perennial grassland cover for the site that will afford watershed protection, reduce fuel loading, retain populations of grassland-associated native plants and provide a prey base of rodents as foraging habitat for native raptors Fencing The purpose of the fencing is to prohibit entry of motorcycles which are currently running unregulated in the area despite signs prohibiting such activity. A K-rail system is proposed to create this barrier. This will allow foot access but preclude vehicular entrance. It also will be useful if burning of the site can be achieved by permit for initial weed eradication. Removal of the non-native weeds The present infestation of weeds can be controlled by initial herbicide use and manual removal of the more localized weeds, such as Fennel (Foeniculum vulgare) and Received: 8/22/OO 8:27PM; 81 S 477 538O -> WILSON ENGINEERING; Page 3 . JUN 22 '00 07:15PM 619^"*7 5380 ' ^ P.3/5 Giant Artichoke (Cynara cardunculm}. Burning is ihe method of choice since it allows retention of vegetative ash which serves as nutrient, as well as destroys the upper portion of the weed seed bed. To this date, permission has not been granted by the Fire Department to bum the site as a training exercise. If burning cannot be used, selective solarization using black plastic over irrigated and germinated seedlings will be done. Minor Recomouring of the site Minor portions of the site have been deformed in association with off-highway vehicular use of the site. These will be reshaped using light earth moving equipment Plant Materials Plant materials to be used in the restoration are selected based on their presence in similar adjacent habitats in the region, particularly at the development site, commercial availability of seed, value to wildlife and successful use in previous revegetation projects. Plant materials arc to be salvaged or collected from native populations at the development site is synchronization of the restoration site can be made prior to implementation of the development. No cultivars or ornamental selections are to be used in the revegetation. Plant materials to be utilized are outlined below. The seeding weights per acre for each species are given in the Table below. Seeding will be clustered to create a more natural plant assemblage and to take advantage of micro-site variations in soils, moisture and exposure. PLANT MATERIALS PLANTING DENSITY (pounds per acre) Aristida purpurea 2 Koehria pyramidata 3 Nassella lepida 1 , Nassella pulchra 3 Vulpia myuros 3 Plantago insularis 3 Additionally, an annual mix of wild flowers will add biological diversity to the grasslands. This mixture would custom spread within the grassland at only specific locations to achieve an attractive visual element. These annuals include the following species with the poundage rates only for purposes of mixture composition, not rates of application per acre, since the material will be spot seeded for visual effect: Castilleja exserta 1 Dichelosfemmci capiiatum 0.5 Eschscholzia californica 3 Gilia capiiala 2 Grindelia robusla 0.5 Hazardia squarrosa 1 Isocoma menziesii 0.5 Rece±ved: B/22/OO 8:28PM; 61Q 477 S38O -> WILSON ENGINEERING; Page 4 JUN 22 '00 07:15PM 619X1*? 5380 ' P.4/5 Lasihema californica 3 Lcyia platyglo.fsa 2 Linanthus dicmlhiflorus 0.5 Lupinus succulennts 5 Penxlemon spectabilis 3 Sisyrinchiitm bellum 1 Plant Establishment x The seed will be applied by hand seeding If the soil surface has become sealed over due to moismrc or compaction, light raking or disking will be needed to prepare the seed bed. Irrigation A temporary, field designed irrigation system is to be constructed in the restoration area. This system will be installed above ground and will have 100% coverage and both manual override and automatic controls. The irrigation system will be completely installed and operable prior to commencing any planting. If solarization with black plastic is chosen to remove weed seedlings, the irrigation system will be uses lo pre-irrigated the site so that seeds will be induced into germination prior to solarization. The enhanced soil moisture is the principal means ofheai killing of the seedlings by solarization. The irrigation system is to be operated for a period of 3 years or less if the revegetation specialist deems it possible to remove the system and city and Fish and Game staff concur. Prior to the removal of the system, its operations will be gradually phased out to avoid stressing newly established young plants. Maintenance Maintenance of the restoration area will be carried out over a 3-year period following the completion of all seeding and planting activities. Maintenance will consist of weed and exotic plant control, plant replacement, control of vandalism, and irrigation. Weed abatement on-site will be performed to control particularly noxious or competitive species which would inhibit the growth of desirable native vegetation. Weeding will be performed as needed to reduce competitive shading or moisture loss over the 3-years of ihe maintenance period. Exotic plants to be removed from the site will include, but will not be limited to, Castor Bean (Ricinus communis), Tree Tobacco (Mcotiava glauca), Sweet Fennel (foeniculwn vulgare), Russian-thistle (Salsola tragus), Bristly Ox-Tongue (Picris echioides), and Cocklebur (Xanthium stnanarium). Other weedy plants which might invade the site will be removed only if they pose a threat to the growth or survival of the target vegetation. Failed starts of seeded materials will be reseeded as necessary in order to achieve the restoration goals or as prescribed by the monitoring program. Replacement planting will utilize seeding only. Where micro-site characteristics are found to be more suitable for Received: S/22/OO 8:28PM; 819 4-77 S38O - =» WILSON ENGINEERING; Page 5 , JUN 22 '00 07:16PM BIS^T 5380 P.5/5 growth of different plant materials, substitution may be made from other species on the list These substitutions are to be directed by the revegctation specialist. The restoration sites will be posted with signs identifying the purpose of the area. Trash dumping, ORV activity and damage to plants and irrigation systems will be controlled by appropriate means. If necessary, sites will be further fenced to control vandalism within the restoration areas. /• Monitoring The restoration site will be monitored for both successful plant growth and biological functioning. Monitoring will be done in October of each year of the 3-year monitoring period. During these monitoring periods, cover and frequency will be determined by line intercept and quadrat sampling techniques. During the monitoring periods, wildlife present at the sites will be inventoried to assess the functional value of the restoration areas. Establishment Success Criteria Restoration will be considered successful if overall recruits from seed exceed 20 plants/meter after a 2-year period. After 3 years, the cover of native plant material should exceed 50%. If restoration sites fail to achieve the minimum success criteria as specified, restoration with container plants will be required to bring these areas up to the "success" level Monitoring reports will be prepared in October on an annual basis and submitted on 30 October of each year. Reports will be submitted to Carlsbad Planning Department and California Department Fish and Game following client review. All aspects of the restoration work, including planting, monitoring and maintenance will be conducted by a qualified revegetation specialist with experience in native habitat revegetation. Wildlife monitoring will be conducted by a qualified biologist with knowledge of local fauna. Work will be funded by Concordia Homes of California, LLC. To ensure the successful completion of all phases of the revegetation work, performance bonds and other security will be posted with the City of Carlsbad. Such security may be released incrementally as portions of the project are completed with the bond to be released at the end of the 3-year monitoring period. The suggested increments for release of securities are as follows: Completion of Planting Phase (includes grading, installation of irrigation, planting of salvaged plants and seeding of all restoration areas). End of third year monitoring and maintenance period (includes final completion of all work and delivery of satisfactory to CDK5).