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HomeMy WebLinkAboutCT 99-08; Spyglass II; Tentative Map (CT) (57)Icidwig Design Group, Inc. November 9, 2001 Van Lynch City of Carlsbad 1635 Faraday Avenue Carlsbad, CA 92008 RE: STATUS REPORT, PERENNIAL GRASSLAND RE-VEGETATION PROJECT FOR THE SPYGLASS DEVELOPMENT, CITY OF CARLSBAD (LADWIG DESIGN GROUP, INC. JOB NO. L-1065) Dear Van: Enclosed is a status report for the perennial grassland re- vegetation project for Spyglass dated October 25, 2001. Mitch Beauchamp, our biologist, showed in bold his intended remedial actions that he is proposing, depending on the upcoming rainy season. Please look the report over and if you have any questions, please call Mitch Beauchamp or myself. Sincerely, LADWIG DESIGN GROUP, INC. Robert C. Ladwig, President RCL:mo Enclosures cc: Terry Stewart, U.S. Department of Fish and Game Kim McKee, U.S. Department of Fish and Game Don Rideout, City of Carlsbad Nancy Gilbert, U.S. Fish and Wildlife Service Michael Ugar, Concordia Homes STATUS REPORT PERENNIAL GRASSLAND REVEGETATION PROJECT SPYGLASS DEVELOPMENT MITIGATION CARLSBAD, CALIFORNIA Donor Site: UTM: 3,670,OOOmN, 470,OOOmE Receptor-Mitigation Site UTM: 3,669,OOOmN, 473,OOOmE Prepared for Concordia Homes of California, LLC 7130 Avenida Encinas, Suite 200 Carlsbad CA 92009-4657 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 619 477 5380 E-mail: bio@psbs.com PSBS # T472B 25 October 2001 R. Mitchel Beauchamp, M. Sc.,President RECEIVED NOV 06 2001 LADWIG DESIGN GR PSBS #T472C STATUS REPORT PERENNIAL GRASSLAND REVEGETATION PROJECT SPYGLASS DEVELOPMENT MITIGATION CARLSBAD, CALIFORNIA 25 October 2001 INTRODUCTION The development of a site at the southeast corner of El Camino Real and Carlsbad Village Drive (Elm Street), called Spyglass II (CT 99-08/SDP 99-04.SUP 99-047 HDP 99-07) impacted a remnant Perennial Grassland by landform alteration of the site. As mitigation for this three-acre impact to native Perennial Grassland, the establishment of a 10.3-acre area of Perennial Grassland was required to fulfill Condition 5 of the Mitigating Measures for the Spyglass II project. This Status Report chronicles actions and results to date to establish that habitat in an area formerly involved with agricultural use and now covered by weedy, non-native grasses and forbs. Intended remedial actions are indicated in bold type. The site is a portion of land owned by the State of California and administered by the Departments of Transportation and Fish and Game as a mitigation bank and natural preserve. The site lies northwest of another area proposed as a mitigation area, called Holly Springs. The site was considered 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 80 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 actions, generally following the plan for the project, dated 13 December 2000, were implemented in the establishment and maintenance of the native, perennial grassland cover for the site that affords watershed protection, reduces fuel loading, retains populations of grassland-associated native plants and provides a prey base of rodents as foraging habitat for native raptors Site Preparation Severe infestations of Fennel (Foeniculum vulgare) and Giant Artichoke (Cynara cardunculus) were selective hand removed and disposed of in a 40 cuyd dumpster. The remaining infestation of weeds was initially controlled by the overall tractor disking to a depth of 6 inches of the entire site. Pacific Southwest Biological Services, Inc. PSBS #T472C Minor Recontouring of the Site Minor portions of the site have been deformed in association with off-highway vehicular use of the site and erosion. These old roads and gullies were reshaped using farming tractor equipment during the site plowing. Solarization In order to destroy the upper layer of the weed seedbed, selective solarization using black plastic sheets was done over rain-moistened soils. The timing of the sheet placement was too early in the season, and adequate killing temperatures were not achieved. Once this problem was determined and the need to seed prior to any further rainfall, this method of weed abatement was abandoned. Seeding Following the attempted solarization treatment of the planting site, the entire site was over seeded by hand with the below cited seed mixture. PLANT MATERIALS PLANTING DENSITY (pounds per acre) Aristida purpurea 2 Nassella lepida 1 Nassella pulchra 3 The following plant material was spot seeded for visual effect: A Ilium praecox 0.5 Bloomerid crocea 0.5 Calochortus splendens 0.5 Castilleja exserta 2 Dichelostemma capitatum 0.5 Eschscholzia californica 3 Gilia capitata 2 Hazardia squarrosa 1 Isocoma menziesii 0.5 Lasthenia californica 3 Layia platyglossa 2 Lupinus succulentus 5 Penstemon spectabilis 3 None of the specialty species could be located for clay endemic plants. These include San Diego Thornmint (Acanthomintha ilicifolid) and Clay Morning-glory (Convolvulus simulans). An attempt will be made during the 2001-2002 rainy season to place these plant materials. Supplemental Plowing The level of weed infestation in selected portions of the site was deemed to be so severe that hand removal was not possible. The decision was made to re-plow these area, about 40% of the site in anticipation of seeding during the 2001-2001 winter season. The level to which the prior native plant seeding would persist after this treatment is unknown. Pacific Southwesl Biological Services, Inc. PSBS #T472C Donor Site Salvage The development site had a substantial amount of salvageable plant materials that were appropriate for transplantation to the receptor site. Prior to grading for development of the site, these plant materials, in the form of salvaged grass clumps, Dichondra clumps, and bulbs and corms, were salvaged by hand from the donor site and directly replanted at me receptor site. The salvaged materials were planted at the plowed, lower, northwestern portion of the project site. Fencing Fencing was placed to prohibit entry of motorcycles, which run unregulated in the area despite signs prohibiting such activity. A K-rail system was placed to create this barrier yet allow for foot access. Plant Establishment Due to the poor level of rainfall that could be utilized by the seeding event, the germination and establishment of the native material was marginal. Small seedlings are still evident and the extent to which this initial seeding is successful will be evident following the next major storm. Re-seeding will be done prior to the next rainy season. Irrigation If by January 2002 rainfall is not adequate the contingency of a temporary, field designed irrigation system will implemented in the restoration area. This system would be installed above ground and will have 100% coverage and both manual override and automatic controls. The irrigation system is to be operated for up to a period of 5 years and probably less if the vegetation responds to an adequate level of establishment. 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 has been largely the hand removal of the more noxious weeds, particularly Cardoon (Cynara cardunculus). Vandalism and trash accumulation have not been a problem at the site, due largely to the investment of the wall structure. Monitoring The restoration site has been monitored for both successful plant growth and biological functioning. Monitoring was done in May and the poor results did not warrant any quantitative measurements due to the low density of seedlings. Pacific Southwest Biological Services, Inc.