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HomeMy WebLinkAboutSHIPLEY NATURE CENTER - 05/0619/91 to 02/08/1999 - Urban For all If ? cle JM ' HE3 CITY OF HUNTINGTON BEACH ���CITY COUNCIL COMMUNICATION njD/1_04,(:��fiwr_44�A(b) WMT"TON MACH To: Honorable Mayor and City Council Members From: Tom Harman, City Council Member Date: February 8, 1999 '`_'� -� t h tit Subject: "H" Item for the February 16, 1999, City Council Meeting D > Urban Forest Project Proposal at Shipley Nature Center = s w n ISSUE: I recently visited the Shipley Nature Center with staff to inspect the dying and decaying Monterey Pine forest. Approximately four acres of the 18-acre nature center was once a magnificent pine forest. Over 400 trees grew in this area providing both the Nature Center visitors and the.. community the many benefits of an urban forest. Beetle blight has taken its toll and destroyed all but a few of the Monterey Pines. This four-acre area is now overgrown with passion vine on top of the decaying pine tree remains. Something needs to be done to clear the area-and reestablish an urban forest on these four acres. Naturally, we would not replant Monterey Pines. There are a variety of native trees that are resistant to the beetle blight and would benefit the nature center's interpretive program. I believe the Huntington Beach Tree Society, along with scouting groups, service clubs, schools, and other community organizations would love the opportunity to help with the replanting. If the city were to clear and prepare the site, volunteers could raise the funds for trees and do the replanting. People could dedicate trees in memory of loved ones or for community service projects. This could be a true community effort. I would like the City Council to consider the following motion: MOTION: Direct staff to develop an Urban Reforestation Program for the four acres of Shipley Nature Center that once was the Monterey Pine Forest, to include: 1 . A cost estimate for clearing and preparing the site 2. A cost estimate for preparing a planting plan 3. Guidelines for community involvement 4. Possible funding sources for implementation and return to City Council for further action. Page Two Honorable Mayor and City Council "H" Item for the February 16, 1999, City Council Meeting Urban Forest Project Proposal at Shipley Nature Center In talking to staff, they estimate it will take 10 to 12 hours of staff time to research and develop this report for City Council. The Shipley Nature Center is one of the cities most treasured assets that provides both educational and environmental benefits to thousands of visitors each year. I believe we must act now to get community involvement to not only save the urban forest, but the entire nature center. TH:RH:gc Cc: Connie Brockway, City Clerk Ray Silver, City Administrator' Melanie Fallon, Assistant City Administrator Sao. �o CITY OF HUNTINGTON BEACH INTER-DEPARTMENT COMMUNICATION To: Karen Foster From: Edward K. Hadfield Fire Protection Specialist ✓� S/�S/�� Date: May 14, 1999 SUBJECT: FIRE HAZARD @ THE SHIPLEY CENTER Dear Karen Foster: Per our meeting at The Shipley Center on May ffh, 1999, I am forwarding you my findings on the potential fire hazards that exist at that location. It is my opinion that a fire hazard does exists within the grounds of The Shipley Center. I base this finding on the following items: 1.There is a heavy fuel loading of ladder fuels. Ladder fuels are light flashy fuels that have a lower ignition point and spread a fire into the heavier fuels in the surrounding area. 2. The heavier fuels within the grounds of The Shipely Center have been affected by disease, drought or taken over by other fuel typing. This has caused a large stand of certain fuels to die. These dead fuels are a potential fire hazard that would certainly add to the problem should a wind driven fire occur. 3. The stands of dead pines are extremely close to the homes located on the backside of The Shiply Center. In addition, the pines are close to the eucalyptus trees within Central Park. The proximity of the eucalyptus trees and dead pines creates a problem of fire extension into the housing tract. 4. The proximity and number of homes within the potential fire area that have shake shingle roofs are great in number. 5. Access and water supply for the Fire Department is hampered by the location and accessibility within The Shiply Center. A wind driven fire would be difficult to extinguish given the fuel loading that I observed. It is my recommendation that the City hire an Urban Forester to review the condition of The Shiply Center and to recommend actions to eliminate the fuels that present a fire problem. Respectfully Sub4'tteGk&VL Edward K. Hadf Fire Protection Snecialist J OS112i98 WED 08:39 F.a1 249 3315 Windi Snellen 1411001 TRTTQN RISK MANAGEMENT 14751 Plaza Derive, Suite K Tustin, CA 92791' (714)734-4610 phone (714)7344614 fax May 12, 1999 Xwen Foster,Risk Manager City of Huntington Beach 2000 Main St.,Huntington Beach,CA 92648 Dear Karen, It was a pleasure meeting with.you and Jim Jones on April 21 at the Shipley Nature Center. The purpose of my visit was to evaluate the exposures and controls presently in place at the Mature Center%ith regards to property and liability exposures to the City of Huntington Beach. We toured the center and Jim gave an account of how the center is maintained during the year by natural means and the park ranger. I would say that even at this time of year,when the wet season is just about to end and the growth in the center should be healthy and green,there is an excessive amount of dead or dry vegetation material that could be an adequate fuel source for a serious xvind swept brush fire within the Nature Center. The two story wood frame homes,some of which have wood shingle roofs that are located about 35'to the north ofthe center could easily be exposed to an out of control brush fire,especially in the dry season in the fall. Much of the growth within the center is 30 to 40 feet or more high and many trees or shrubs are dead or dying. The major source of the problem as Jim explained is that the wild growth of Passion'Vine has overgrown many of the trees and shrubs,preventing adequate light from getting to them and weakening therm if not killing them off completely. There is of course,also naturally aging and dying material in the center which is not removed by lae park ranger. The center has a single story brick and steel visitor center building with windows that could also be destroyed in a brush fire. The source of ignition could be from a carelessly discarded cigarette from users of the adjacent public park grounds,lightening or even arson. A serious property and Iability exposure to the public exists at the nature center. Steps should be taken to ensure that the excessive dead vegetation is removed on a regular basis. Additionally,near the northeast corner of the center is a group of three large,older Eucalyptus trees that have apparently never been trimmed. One of the trees has a major branch well over SO feet in length growing out over the trail where people take nature hikes. This branch in particular presents a possible serious liability exposure to the public using the center and should be cut back or removed. Sincerely. 9 Russell Hemken Loss Control Consultant Triton Risk Management REQUESP FOR CITY COUNCI ACTION Date May 6, 1991 Submitted to: The Honorable Mayor and City Council Submitted by: Michael T. Uberuaga, City Administratoorv -j4'­6-T� Prepared by: Ron Hagan, Director, Community Services Subject: SHIPLEY NATURE CENTER IMPROVEMENTS APPROVED BY CITY COUNCIL S� 6 1v�L Consistent with Council Policy? [ ] Yes [ ] New Policy or Exception . -- -- ERK Statement of Issue, Recommendation,Analysis, Funding Source,Alternative Actions, Attachments: SAM S TAT EMENT OF 1..S3_LE. There is a need to provide wetland mitigation for the Waterfront project at the Huntington Central Park Shipley Nature Center. RECOMMENDATION Approve the concept of the Shipley Nature Center Habitat Enhancement and Creation Program. ANA .Y�®S T S Mayer Corporation must provide off-site mitigation for approximately .8 acre of severely degraded wetlands at Pacific Coast Highway and Beach Boulevard as part of the Waterfront Development for the extension of Pacific View Avenue. After exploring potential areas with Vail , Speck, Taylor, Inc. , state agencies, Victor Leipzig, and Mayor Peter Green, the Mayer Corporation has determined that the most viable location is Shipley Nature Center in Huntington Central Park. Project calls for the expansion of the existing nature center pond, thereby creating additional wetlands- habitat in Huntington Central Park. This enhancement to the nature center will not only provide an extension of the existing natural habitat, but will also expand the educational and enjoyment benefits for park users . The nature center is a pr;ime attraction as an excursion for local school children as well as by individuals and families who visit Central Park. This program will also improve the aesthetic experience of visitors by creating the illusion of being removed from the surrounding urban landscape. In addition to the expansion of the pond, the plan calls for the enhancement of the existing habitat in the nature center to focus on the irradication of exotic invasive species and development of native habitat structure. The project is being designed to reduce and/or eliminate some of the existing maintenance problems and to create a new area that will have minimal impact on city 4 P10 5/85 REQUEST FOR CITY COUNCIL ACTION Page Two maintenance crews. Funding for grading and replanting activities to create wetlands, short and long-term maintenance procedures during the two year monitoring period, and supplemental plantings required during the five year monitoring period will be provided by the Robert Mayer Corporation. As is the case with the existing pond, the new section will not always have water in it based on the season, water table and rain levels . Alternate methods of keeping more water in the pond for extended periods of time are being explored. These options will not, however, include filling the pond with potable water. Staff feels that the Mayer Corporation and the city' s redevelopment agency have a viable solution to mitigate the severely degraded wetlands area at Pacific Coast Highway and Beach Boulevard. At the same time, the community receives improvements to the Donald S. Shipley Nature Center. The State Department of Fish and Game, Army Corps of Engineers and the Huntington Beach Community Services Commission have approved this concept of mitigating Pacific Coast Highway wetlands by making these improvements at the Shipley Nature Center. FUNDING SOURCE The Robert Mayer Corporation ALTERNATIVE ACTIONS Do not permit Mayer Corporation to make improvements in Shipley Nature Center. ATTACHMENT Shipley Nature Center Plan Location Map Shipley Nature Center Habitat Enhancement and Creation Program prepared by Vail , Speck, Taylor, Inc. RH:am I I i I I ( I I I E �� 1 za .pli^ATTAIL9 \-PROPOSED LRDTOFGAADRIG uY �r', l - I IRWSf10 TA k _mRIG POND 1 sTRV VRE .. SROR',,v f DPECI[G PROPOSEDLIMR I�r ycrt.LQ&R J OF GRRDR4 4 I ;.:fl ORF DERV A PROPOSED LEGEND 'EXmwB l� 'EMEPCER=G {., E9 PF POPULUSFREMOtTTI! /7-. - I :"�_a_��/ -�+•'..,'. - lx '=)/./'u ... FREMONT COTTONWOOD �CC[ ST SALIX TREE SPECIES WILLOWS-VAR. SM SALIX MIXTURE OF SPECIES SPE`GE9 GG WILLOWSVAR. ...-.._......_ YI�FfNO .,.._. .. $$ SALIX SHRUB SPECIES ....._ •---.WBAAOW_W-fX-MBIOLFPIC BG BACCHARIS GLUTINOSA W4IAR`41 Exl IJULE AT MULEFAT SCRUB R dXN rm"EDW60w, SE SHORELINE SPECIES MIXED WITH SEED OF EMERGENTS ES EMERGENT SPECIES- w� SCRIPUS ROBUSTA 9XISTR90 A„IRS BULRUSH,ALKALI S. LNEYI- L BULRUSH, W�LNWFY S.CALIFORNICUS-CALIFORNIA BULRUSH EnsT a PROPOSED NOISE eERM ALONG GOLDEN WEST AVENUE EXISTING NATURE CENTER POND TO BE EXPANDED WETLAND.—ATION AREA WITH SPECIES NOTED EXISTING NATURE CENTER VEGETATION TO REMAIN *TRAIL SYSTEM I ACCESS PROGRAM TO BE DEVELOPED AS A PART OF THE IMPLEMENTATION PLAN MUHRMUMH FLU F OO F-1-52 7H E w/%u E M[P L721amv pCNOi E c u SHIPLEY NATURE CErhi" TER o to rF .R .P u+yy FI•E. x. uu l �xS.ry A% rlifl'Ert'.eFR lit(T/.I�CeI it ^^ •^J. I; �S 'c9 FF� q� cl) w 0 o � Q > cc z = m w C� w m WARNER SLATER SHIPLEY NATURE TALBERT CENTER HUNTI NGTON ELLIS CENTRAL PARK A GARFIELD coco gs r � o m c,° a w - m A oC MAP wTar F.a 4Yw V.'M�I Intl`..fOAA/4f!)Nl l3{lL) i SHIPLEY NATURE CENTER HABITAT ENHANCEMENT AND CREATION PROGRAM Prepared for: Robert Mayer Corporation 660 Newport Center Drive, Suite 1050 Newport Beach, California 92658 Prepared by: Vail Speck Taylor, Inc. 4 Executive Circle, Suite 150 Irvine, California 92714 Contact: Eileen Brown September 20, 1990 r , TABLE OF CONTENTS Page I. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . 1 Description . . . . . . . . . . . . . . . . . 1 Existing Conditions . . . . . . . . . . . 1 Program Summary . . . . . . . . . . . . . . . . . . . . 1 II. EXISTING RESOURCES . . . . . . . . . . . . . . . . . . . 3 Biology . . . . . . . . . . . . . . . . . . . . . . . 3 Hydrology . . . . . . . . . . . . . . . . . . . . . . . _ 4 Topography . . . . . . . . . . . . . . . . . . . . . . . 5 Soils . . . . . . . . . . . . . . . . . . . . . . . . . 5 III. HABITAT ENHANCEMENT AND CREATION ISSUES . . . . . . . . 6 Habitat Structure and Exotic Vegetation . . . . . . . . 6 Soils . . . . . . . . . . . . . . . . . . . . . . . . . 6 WaterSources . . . . . . . . . . . . . . . . . . . . . 7 Aesthetics . . . . . . . . . . . . . . . . . . . . . 7 Access . . . . . . . . . . . . . . . . . . . . . 7 Vector Control . . . . . . . . . . . . . . . . . . . . . 7 Encroachment by Domestic Pets . . . . . . . . . . . . . 8 IV. ENHANCEMENT PROGRAM . . . . . . . . . . . . . . . . . . 9 Enhancement of Existing Habitats . . . . . . . . . . . . 9 Concept . . . . . . . . . . . . . . . . . . . . . . . . 9 Eradication Program . . . . . . . . . . . . . . . . . . 9 Trails . . . . . . . . . . . . . . . . . . . . . . . . . 10 Replanting . . . . . . . . . . . . . . . . . . . . . . . 10 Maintenance . . . . . . . . . . . . . . . . . . . . . . 10 Educational Center Services . . . . . . . . . . . . . . 10 Funding Mechanisms . . . . . . . . . . . . . . . . . . . 10 V. WETLANDS CREATION PLAN AND SPECIFICATIONS . . . . . . . 12 Mitigation Opportunities . . . . . . . . . . . . . . . . 12 Location . . . . . . . . . . . . . . . . . . . . . . . . 12 Habitat Concept . . . . . . . . . . . . . . . . . . 12 Wetlands Creation Plan Methods . . . . . . . . . . . . . 12 Grading Plan . . . . . . . . . . . . . . . . . . . . . . 13 Planting Plan . . . . . . . . . . . . . . . . . . . . 13 Water Supply . . . . . . . . . . . . . . . . . . . . 13 Soil Treatment . . . . . . . . . . . . . . . . . . . . . 14 Vector Control . . . . . . . . . . . . . . . . . . . . . 14 Performance Standards/Replacement . . . . . . . . . . . 15 Schedule . . . . . . . . . . . . . . . . . . . . . . . . 15 Irrigation . . . . . . . . . . . . . . . . . . . . . . . 15 Maintenance and Monitoring . . . . . . . . . . . . . . . 16 Responsible Parties . . . . . . . . . . . . . . . . . . 17 Funding . . . . . . . . . . . . . . . . . . . . . . 17 SHIPLEY NATURE CENTER RESTORATION PROGRAM I. INTRODUCTION Description The Shipley Nature Center is a component of Huntington Central Park, located in the City of Huntington Beach near Golden West Boulevard and Talbert Avenue (see Vicinity map) . The Center provides opportunities for visitors to view a variety of natural processes. In addition to managing and maintaining wildlife habitat, it also provides educational services for the public. The purpose of the program delineated below is to articulate habitat goals and objectives for the Shipley Nature Center. Within the framework of the program, details are provided for the enhancement of portions of existing wetlands and creation of additional wetlands habitat. Existing Conditions A variety of habitats exist in the center: oak, pine, willow, redwood, alder/sycamore, grassland/shrubs and wetlands (see Existing Vegetation Exhibit) . Several of the desired native species are competing with invasive exotic species, such as castor bean, passion vine, and tamarisk. The wetlands vegetation is dependent upon localized irrigation and ground water. The water level in the pond at the south-eastern corner of the area fluctuates according to the groundwater supply, which in turn affects the type and density of wetlands vegetation surrounding the pond. Program Summary The objectives of the enhancement program are as follows: o Maintain and enhance a variety of natural habitats within the Shipley Nature Center for the education and enjoyment of visitors; o Develop a maintenance program which does not conflict with California Department of Fish and Game criteria for wetlands habitat and is compatible with City of Huntington Beach mosquito abatement considerations; o Identify means by which the community can support and contribute to the management of the Shipley Nature Center; and o Create additional wetlands habitat. 2 �S qy- w � > a: z Q -' Q w = m O U w O C'3 C� w m WARNER SLATER SHIPLEY NATURE TALBERT CENTER HUNTI NGTON ELLIS CENTRAL PARK A 9C�•c� GARFIELD CO'9S' � w o 'S► z '9y �Ov Q w m A Oc�'�ti VICINITY MAP - rL�►T II. EXISTING RESOURCES Biology The Shipley Nature Center contains woodlands and wetlands which serve as an urban wildlife refuge, particularly for avian and invertebrate species. The City of Huntington Beach is located on land that was historically covered with marshland, springs and ponds. Alterations of the natural hydrology along with deposits of fill material have created upland areas which no longer support wetland ecosystems. The Nature Center landscape now contains a functioning wetlands including a range of habitat types from freshwater marsh to willow woodland. Other areas of the center are defined by mass plantings of California native trees, with occasional exotic specimens dispersed about the center. Supplemental irrigation is used to maintain many of the trees. The remaining areas have been maintained as mixed grasslands although large portions of them are heavily invaded by ruderal species. The greatest area of tree canopy is comprised of black and . arroyo willows, Salix gooddingii and S. lasiolepis. (See Existing Vegetation Exhibit. ) Monterey pines (Pinus radiata) form a dense canopy over the northwest section. White alders (Alnus rhombifolia) line the southeastern perimeter of the nature center and are accompanied by California sycamores (Platanus racemosa) near the entrance and the southwestern corner. A linear planting of coast redwood (Sequoia sempervirens) borders the alders on the southeastern boundary. Several plantings of relatively immature coast live oak (Ouercus agrifolia) with spreads of approximately fifteen to twenty feet, form a stand just east of the interpretive center. With the exception of the willows, these woodlands are generally characterized by a lack of complimentary understory vegetation with little or no structural stratification other than that provided by weedy exotic species. In addition to the willow woodlands, wetland vegetation is represented by emergent species such as cattail (Typha sp. ) and California bulrush (Scirpus californicus) , as well as shoreline species such as water smartweed (Polygonum punctatum) and marsh fleabane (Pluchea purpurascens) . Current city vector control practices discourage natural stands of the emergent plants, which in the Shipley Nature Center, have been reduced by city maintenance crews to a few isolated patches through manual clearing and herbicide applications. During site visits made in mid-August, 1990, virtually no viable tule habitat existed. Small patches of mulefat (Baccharis glutinosa) occur in isolated areas, but 3 lack the density needed to provide good cover for wildlife. Several portions of the wetlands are being colonized by the invasive giant reed (Arundo donax) . As well as being a tenacious competitor with native wetland vegetation, this species offers little in terms of habitat for avian and other native faunal species. Among the other invasive exotic species castor bean (Ricinus communis) , salt cedar (Tamarisk) species and passion flower (Passiflora caerulea) comprise the greatest threat to the integrity of the nature center habitats. The castor bean has begun to overtake the open grassland areas in the southeastern portion of the site. Mature castor bean plants at the north eastern corner of the site include some specimens with trunk diameters of eight inches or more. Salt cedar, an Asian species that is an invasive weed in many desert riparian systems, has become established in several locations around the center. This species competes heavily with adjacent plants for available water, typically resulting in dense monocultural stands over time. The passion vine is responsible for attracting a multitude of gulf fritillary butterflies (Agraulis vanilli) to the site, whose larvae feed on the plant. While these bright orange winged creatures are a striking feature of the nature center, they are not a native species and their weedy host plant tends to dominate the landscape to the detriment of less aggressive native species. The particular species of passion flower at the center is not the one grown commercially for fruit, but does bear fruit which are eaten by certain birds, facilitating the dispersal of seeds. However, these fruit are not particularly favored, as evidenced by the large numbers of fruits left untouched on the vines. In addition to its alteration of wildlife habitat structure and function, the passion vine is observed to be competing vigorously for light with any plant it can climb over. It has formed a blanket over some of the coast live oaks, as well as spreading out over portions of the grassland and twining through the willows. If left unchecked, this encroachment may seriously weaken many desired species, most notably, the oaks. Hydrology The nature center wetlands are reputed to be fed primarily by ground water, augmented by urban runoff and localized irrigation. Fluctuations in the level of the aquifer over the last fifteen years have resulted in a shifting mosaic of wetland habitat types surrounding the pond. It is believed that these shifts have resulted from yearly fluctuations in the rainfall feeding the aquifer. However, increased draw- 4 down of the aquifer and alterations of the hydrology of adjacent areas may be factors, as well. This summer, Park Ranger Dave Winkler has reported that the pond would have gone completely dry except for the addition of runoff from a broken water main in early August. In late August, it was necessary to hose feed water into the -pond to keep the mosquito fish alive. Current low-water conditions support willows at -2 feet and below, wetland forbs at elevation -4 feet and the emergent bulrush and cattails at -6 feet. Topography The existing topography shown in the exhibits is based on a map provided by the City of Huntington Beach which illustrates the design concept for the nature center. It is assumed that the contour line labeled as "O" indicates mean sea level. No as-built drawings of the center were prepared. Visual inspection of the site indicates the map to be reasonably accurate. Generally, the site slopes gradually downward toward the pond area, where an ultimate depth of -7 feet below sea level is reached. The highest elevations occur on the southeast portion of the site, corresponding to the elevation of Golden West Avenue and reaching a maximum of 6 feet above sea level. soils A mixture of soils occurs on the site as a result of miscellaneous landfilling activities of the past. The most obviously distinguishable soil is a rich dark peat which occurs over most of the wetland areas. As a result of the decreasing ground water level, the shrunken peat has formed fissures which reveal the depth of the material to be at least one foot or greater. As the water has receded, the peat has served to hold water for the remaining wetland forbs. The fill areas, including much of the area managed as grassland appear to be poor in organic matter and nutrients as evidenced by their heavy colonization by opportunistic weedy species. These opportunists readily invade poor soils that will not support more sensitive native species. 5 III. HABITAT ENHANCEMENT AND CREATION ISSUES Habitat Structure and Exotic Vegetation While the nature center currently provides a variety of tree canopies as wildlife habitat, it lacks most of the understory species which would be present in the corresponding native plant communities. Stratification of the vegetation into vertical layers is weak in many areas and virtually absent in some. In many cases, these niches are currently filled by non-native invasive species which have low or limited value as habitat for native and migratory fauna. Shrub massings are conspicuously absent for such an area in Southern California where scrub communities play such an important role in the natural landscape. De Graaf (1986 a and b) and De Graaf and Chadwick (1984) have reported on the natural association of avian (bird) species in groups termed guilds, based on the vertical and horizontal structure of their natural habitat. One of the implications of their work is that in landscapes where one or more vertical levels of vegetation are missing from the habitat, the avian guilds which would normally occupy those levels will be absent, resulting in an overall decrease in potential biodiversity. Applying that concept to the Shipley Nature Center, it follows that developing habitat structure more representative of undisturbed native plant communities will increase the biodiversity the landscape can ` support. Habitat enhancement plans should consider local native plant communities as models for enhancement goals. In addition to their alteration of habitat structure, many weedy exotic plants serve as food sources for relatively few urban-adapted wildlife species. These urban wildlife species can likely find suitable food sources in many areas of the urban landscape. The nature center can be a refuge for species less suited to urban situations, if appropriate food and adequate cover are maintained. Such enhancement would strengthen Shipley's role as an educational center by exposing visitors to species they may not see elsewhere in the urban environment. Soils It is suspected the area south of the pond may have historically been a landfill. The appearance of asphalt remnants on site also suggest that a paved roadway may once have traversed the area. Soils testing should be conducted to determine whether or not the ground can support riparian vegetation such as willows and sycamores. 6 Water Sources The healthy appearance of the existing willows and other wetland vegetation suggests that sufficient water exists on the site for the creation of additional wetlands. Further hydrologic studies may be conducted as determined necessary for the final plan. Aesthetics The ambiance of the nature center is seriously affected by traffic noise from Golden West Avenue. The proposed widening of the road will intensify the problem. Inasmuch as solid barriers are known to be the only effective means of noise attenuation, the possibility of creating such barriers deserves consideration as a part of the overall enhancement of the nature center. Access Access to the Huntington Central Park is provided by Slater and Golden West Avenues (see Vicinity map) . Golden West Avenue is adjacent to the Shipley Nature along its eastern edge. City of Huntington Beach transportation improvements include realignment and expansion of Golden West. The extent of the road improvements needs to be determined, particularly in respect to potential impacts to the Shipley Nature Center. 6 Within Shipley Nature Center, access is provided by dirt paths. The dirt paths become muddy during the rainy season, discouraging use by some park visitors. Alternative path materials should be identified that are relatively . inexpensive, easy to maintain, able to provide year-round service to park visitors, and be consistent with the tone of the Shipley Nature Center. Vector Control Due to conflicts with the current implementation of community vector control objectives, the areas around the pond which would normally support emergent species such as bulrushes have been cleared of their valuable habitat. While enhancement and expansion of the wetland areas surrounding the pond will be biologically beneficial, it must be accomplished in such a manner that mosquito growth would not be encouraged. Wetlands expansion and on-going maintenance procedures must include features that will avoid future conflicts with vector control requirements. 7 Development of the enhancement plan will include the evaluation of alternative strategies which would allow for the co-existence of emergent vegetation with mosquito fish (Gambusia affinis) . Encroachment by Domestic Pets Situated as it is in close proximity to residential development, domestic pets constitute a serious threat to nature center wildlife. Cats pose the biggest threat inasmuch as they can easily circumvent the fences to gain access to the grounds. Currently, there are virtually no areas of the center which cannot be penetrated by feline carnivores. Development of a sanctuary from domestic pets is a worthwhile goal for enhancement activities. 8 IV. ENHANCEMENT PROGRAM Enhancement of Existing Habitats A plan for the enhancement of existing habitat in the entire nature center will be developed, focusing on the eradication of exotic invasive species and the development of native habitat structure. Understory plant palettes and planting concepts will be developed for each of the woodland areas, with native ecosystems as design models. A management strategy for stabilizing grassland areas will be included. The wetland creation program will focus on the areas south of the existing wetland. Concept The concept of the enhancement program will be to enhance the existing habitats based on the goal of mimicking native California environments and improve the aesthetic experience for visitors by creating the illusion of being removed from the surrounding urban landscape. A sound berm using material from the wetland creation could be created along Golden West Avenue, where existing vegetative constraints allow. Eradication Program 1. Targeted Species The primary species targeted for eradication are the following: giant reed (Arundo donax) ; brazilian pepper (Schinus terebinthefolius) ; salt cedar (tamarisk sp. ) ; castor bean (Ricinus communis) and passion flower (Passiflora caerulea) . Through in-field analysis, invasive species will either be thinned or eradicated. Plants will be thinned if they provide certain wildlife benefits. 2 . Methods Removal methods will initially involve application of a systemic herbicide such as Round-up or Rodeo. Removal of Arundo donax will be phased in order to allow desired species to take over the functions it currently serves in defining space and as a visual screen. Plant removal within the marsh or immediate vicinity of the pond will rely upon primarily mechanical methods with the use of herbicides being minimized. 9 Trails Trails throughout the Shipley Nature Center currently are primarily marked through vegetation clearance and compacted soil. In order to improve the permanence of the trails and to avoid muddy trails, decomposed granite or other appropriate material will be applied to the trails. A potential alternative to decomposed granite is the chipped/shredded trimmings from park landscape maintenance. Reapplications of such material would yield a soft (mulch- like) surface which is comfortable to walk on. Certain trimmings, such as those from Eucalyptus sp. have allelopathic properties which could help reduce weed encroachment upon the trails. Vegetation along trails will be trimmed and decomposed granite or other material restocked annually, and as needed following heavy rainfall. Replanting Replanting of the sound berm will be implemented using a combination of seed and container grown material and revegetation techniques. Some willows will be propagated by cuttings.. Native grassland and coastal sage scrub species will be used. The feasibility of using seed drilling techniques will be compared with the expediency of hydroseeding for effectiveness of establishing slope vegetation. Maintenance Alternative maintenance programs for each habitat type will be developed based on the nature of the labor force to be employed (i.e. volunteer, court referral or municipal employees) . Educational Center Services Under the direction of the Park Ranger, additional educational materials will be developed (e.g. , signage, posters, educational materials for distribution) . Funding Mechanisms The City of Huntington Beach will retain responsibility for the overall maintenance of the Shipley Nature Center. Due to the workload of the Huntington Central Park maintenance crew, the ideal enhancement and maintenance solution would 10 be an additional person to assist the Park Ranger. This solution would require additional funding from the City of Huntington Beach to create such a position. Since such funding from the City of Huntington Beach may not be readily available, alternative funding sources must be considered. For example, additional funds can be generated through collection of recyclable materials within the Huntington Central Park (e.g. , aluminum cans, plastic bottles, or glass bottles) . The collection of aluminum can be augmented by requesting schools to bring one aluminum can for every child visiting the Shipley Nature Center during a field trip. Additional funds can also be generated by placing a display requesting donations from people visiting the Center. In addition to funding sources, the Shipley Nature Center should also explore potential sources of free, volunteer, or inexpensive labor. One option for free labor would be the use of temporary manpower supplied through individuals required to provide community service. To implement this option, the Shipley Nature Center would apply to participate in the court referrals program. Individuals directed to fulfill their community service commitment at the Shipley Nature Center could be utilized by the Park Ranger to complete weed removal and other labor intensive maintenance projects. Another alternative source for manpower would be through community service organizations volunteering their time to the Shipley Nature Center (e.g. , Boy Scouts or Rotary) . Inexpensive labor could be secured through contacts with the local community colleges and universities for student interns interested in plant ecology or landscape architecture. The above options for labor would require close supervision, reaffirming the need for an assistant to the Park Ranger. 11 V. WETLANDS CREATION PLAN AND SPECIFICATIONS Mitigation Opportunities The proposed wetlands creation is a public/private joint venture to mitigate for 0.8 acre of wetland lost to development on land owned by the City of Huntington Beach Redevelopment Agency. Location Creation of new wetland habitat will occur to the south of the existing wetland. Habitat Concept The wetland is conceptually designed to provide a diversity of micro-environments including upland riparian tree and shrub cover, shoreline, marsh and open water habitats, hydrologic and soil conditions permitting. Wetlands Creation Plan Methods Development of a successful enhancement program requires a carefully executed step-wise methodology to maximize the probability of successful wetlands creation. Since many wetlands restoration programs have failed due to inadequate methodology, strict adherence to the steps delineated below is critical. Additional baseline information will be collected. Soils testing will be conducted within the vicinity of the pond for those areas being considered for wetlands creation to determine soil's ability to support wetlands vegetation. In order to assure coordination between on-going wetlands habitat maintenance and Orange County vector control requirements, mosquito abatement and maintenance procedures will be developed which are able to fulfill the objectives of both endeavors. Current and historical hydrologic patterns surrounding the pond will also be evaluated to verify the ability of the area to support expanded wetlands habitat without permanent irrigation and minimal artificial management involvement. Grading will be designed to provided for a diversity of microhabitats as well as aesthetic function. All earth manipulations will be designed in accordance with local, state and federal agency requirements. In order to assure successful implementation, short and long-term maintenance procedures will be included. Several recommendations for financing and/or community support are provided to assist the City of Huntington Beach in developing the means to augment current management programs. 12 Funding for grading and replanting activities to create wetlands, short and long-term maintenance procedures during the five year monitoring period, and supplemental plantings required during the five year establishment period will be funded by The Robert Mayer Corporation. Grading Plan Based on the results of soil and hydrologic evaluations, as well as an accurate topographic survey of the areas involved in the wetland creation, a detailed grading plan will be developed which allows for appropriate drainage as water levels fluctuate in the pond. An island will be created by excavation of channels. The Wetland Grading Concept Exhibit depicts a conceptual study of the grading design. Planting Plan Specifications for the planting plan will be developed based upon the final grading plan. Tree species for the- upland areas will include fremont cottonwood (Populus fremontii) , Mexican elderberry (Sambucus mexicana) , and black, red and arroyo willows (Salix gooddingii, S. laevigata and S. lasiolenis) . Riparian shrub masses will be dominated by mulefat (Baccharis glutinosa) . Shoreline areas will be revegetated with a range of shoreline to emergent species to accommodate fluctuating water levels. Species will include water smartweed (Polygonum punctatum) ; marsh fleabane (Pluchea purourascens) ; monkey flower (Mimulus guttatus) ; watergrass (Echinochoa crusgalli) . If soil conditions are appropriate, saltgrass (Distichlis spicata var. stolonifera) and yerba mansa (Anemopsis californica) will be planted on the upper margins of the marsh. Emergent areas will be planted with a combination of seeds and liners consisting of bulrushes such as Olney's (Scirous olneyi) , alkali bulrush (S. robusta) and California bulrush (S. californicus) . Water Supply The newly created wetland will be fed by the groundwater that currently supports the existing wetland. The elevation of all new wetlands will be at or below the elevation of the upper limits of the existing wetland vegetation, from four to six feet below sea level or lower. Inasmuch as this baseline observation is made on conditions imposed by several years of drought, the proposed concept is highly likely to be successful through wet and dry years. 13 Soil Treatment Valuable wetland soil will be conserved for use in the newly created wetland. Organic amendments will be added to existing soils where necessary to produce the desired wetland soil type. Leaf litter from existing willow woodlands will be distributed over the surface of newly created riparian areas to encourage the development of mycorrhizae and other soil organisms important to the functioning of riparian ecosystems. Vector Control The agency responsible for overseeing vector problems for the City of Huntington Beach is Orange County Vector Control District. According to Dr. James Webb of that organization, the agency's preferred methods for mosquito abatement are, in order of preference: 1. Source reduction.; 2. Biological control (mosquito fish) ; and 3. Pesticide. Source reduction can be accomplished by eliminating pools of stagnant water in which biological controls such as mosquito fish are not functioning. Pools which would otherwise accommodate mosquito fish can lose this function when vegetation becomes too dense to allow access for the fish. Larry Shaw of the Vector. Control District has further elaborated that, in addition to congestion caused by the increase of live vegetation, considerable vector problems result from the accumulation of dead vegetation, particularly cattails. The wetland concept addresses the source reduction and biological control by design and proposed management. One strategy which will be evaluated for maintaining tule vegetation in the existing and created wetlands while providing vector control would be the maintenance, through hand-clearing, of channels surrounding small stands of bulrush and cattails. These channels would allow the mosquito fish to circulate through a greater portion of the wetland, thereby keeping mosquito larvae in check. Dead vegetation would also be removed by hand-clearing. In the newly created wetlands, one possible technique for limiting bulrush and cattail stand density would be the placement of impervious barrier materials (broken concrete rubble or small boulders) on the soil surface at intervals which would allow the growth of bulrushes between. While this may not be the normal strata underlying a marsh, such a technique may represent a viable compromise which would allow a greater area of emergent vegetation than is currently allowed to exist on the site. This approach would also include periodic hand-clearing of dead vegetation. 14 These measures will allow for the continuous flow of water through the bulrushes, thereby allowing passage for the mosquito fish (Gambusia affinis) which controls the mosquito population. If necessary, pesticide may be employed. However, the recommended pesticide for this purpose, BTI, is actually a form of biological control. BTI is an acronym for the bacteria Bacillus thuringiensis israelenis which feeds on the mosquito larvae and is innocuous with respect to other organisms in the wetlands. This approach is preferable to the practice imposed by the city's current maintenance practice of applying herbicide to the tules. The primary drawback to using BTI is that it requires the monitoring of the mosquito population. This would be an appropriate task for the Orange County Vector Control District. Performance Standards/Replacement After the first year, coverage by woody and herbaceous species should be at least 50%. As a guideline, survival of at least 80% of the original container plantings will be required one year after planting. Three years after planting the tree-sized willows should be a minimum of 9 to 12 feet tall, sycamores should be 5 to 10 feet tall (depending on container size) , and cottonwoods should be 7 to 13 feet tall. After five years, willows should be 15 to 18 feet tall, sycamores should be 9 to 18 feet tall, and cottonwoods should be 12 to 20 feet tall. If these performance standards are not achieved after five years, replanting or other corrective measures will occur, if necessary, and monitoring will continue until the performance standards are attained. These standards may be waived by the California Department of Fish and Game if field inspection shows good growth and functional habitat. The wetlands creation design will minimize potential vector (e.g. mosquito) problems that may require control measures which would result in disruption of the riparian vegetation. Schedule Planting should take place during the rainy season of 1991, (between November, 1991 to March, 1992 at the latest) . Irrigation A drip irrigation system will be provided for a minimum of two years to ensure establishment of the planted vegetation. 15 Maintenance and Monitoring 1. Maintenance: Short-term Prior to planting, all invasive weeds will be removed employing mechanical methods and/or EPA-labeled herbicides. If deemed necessary by the implementing contractor or site monitor, supplemental planting and/or seeding during appropriate planting periods may be necessary due to environmental factors such as insufficient precipitation or frost. Short-term maintenance will be provided by The Robert Mayer Corporation. 2. Maintenance: Long-term The maintenance of revegetated areas will be the responsibility of the Huntington Central Park Maintenance Crew. Long-term maintenance will be provided by the park maintenance crew under the direction of the assistant to the Park Ranger. 3. Monitoring The site will be monitored by the Park Ranger, or a qualified designee. The monitor shall be present at all pre-grading meetings and during grading activities. The monitor shall concur that all appropriate remedial protective measures have been taken, prior to grading of any areas in the Shipley Nature Center. Monitoring of plantings will occur at 30 days and 90 days after initial planting to determine success of establishment. Monitoring of survival will continue every six months for two years after planting. Corrective actions will include monitoring for growth and coverage for the next three years, replacement of dead container plantings and/or reseeding in areas as necessary to meet the performance standards. If replacement is necessary, The Robert Mayer Corporation will be responsible for replanting. Semiannual reports for the first year and annual thereafter, which include evaluation of survivorship, development of the habitat and actions taken, will be prepared by the site monitor, and will be submitted to the City of Huntington Beach and California Department of Fish and Game. Corrective actions will be taken within 14 days upon identification of any problems by The Robert Mayer Corporation. 16 The monitor shall have authority to temporarily direct, divert or halt grading to allow sufficient time to install protective devices, transplant vegetative resources to safe zones, or modify grading to protect/preserve the resources in place. Responsible Parties In connection with The Waterfront project, The Robert Mayer Corporation will be responsible for the grading and replanting activities associated with wetlands creation. The Robert Mayer Corporation will also be required to implement any replantings or reseeding deemed to be necessary by the on-site monitor during the five year monitoring period. Funding Funding for grading and replanting activities to create wetlands, short and long-term maintenance procedures during the two year monitoring period, and supplemental plantings required during the five year monitoring period will be funded by The Robert Mayer Corporation. 17 r REFERENCES De Graaf, Richard M. and Nan L. Chadwick, 1984 . "Habitat Classification: a Comparison Using Avian Species and Guilds. " Environmental Management Vol. 81 No. 6, pp. 511-518. De Graaf, Richard M. , 1986a. "Urban Bird Habitat Relationships: Application to Landscape Design. " Transactions of the North American Wildlife and Natural Resource Conference Vol. 51 pp. 232-248. De Graaf, Richard M. , 1986b. "Urban Wildlife Habitat Research - Application to Landscape Design" in Adams, Lowell W. and Daniel L. Leedy, Editors: Integrating Man and Nature in The Metropolitan Environment; National Institute for Urban Wildlife; Columbia, Maryland. tebO48 18