Enhancing Connections and Restoration within Otay Valley Regional Park

Enhancing Connections and Restoration within Otay Valley Regional Park

The Resource Conservation District of Greater San Diego County (RCD), in partnership with the City of San Diego, proposes to conserve, restore, protect, or enhance, and assist in the recovery of California native fish and wildlife, and the habitat upon which they depend, and to restore or provide habitat for California native fish and wildlife. The Project will benefit native species by restoring and enhancing approximately 15 acres of Diegan coastal sage scrub and native grassland habitats. The native species that are expected to benefit from this Project include plant species such as: coastal sage scrub oak (Quercus dumosa), coast live oak (Quercus agrifolia), California sycamore (Plantanus racemosa), Fremont cottonwood (Populus fremontii); and sensitive bird species such as coastal California gnatcatcher (Polioptila Californica californica), and least Bell’s vireo (Vireo bellii pusillus). Native invertebrates will also benefit from the improved habitat, including Crotch’s bumble bee (Bombus crotchii), a candidate for listing under the California Endangered Species Act. Project activities will include non-native and invasive vegetation removal, improving water quality through the creation of four detention basins with bioswales, native vegetation planting, and maintenance and monitoring. Non-native and Invasive Vegetation Removal: Non-native and invasive plant species, including an approximate 8-acre stand of eucalyptus (Eucalyptus spp.) trees, will be removed throughout the Project area. The trees will either be fully removed or stumped mechanically with the use of light and/or heavy machinery. Stumps may be ground down or left in place to avoid ground disturbance. Herbicide may also be strategically applied to supplement mechanical methods to remove invasive plants. Approximately ten eucalyptus trees will be retained for the benefit of raptor species. Contouring of the Project area using heavy machinery will occur to enhance natural hydrologic processes. Woody material may be milled or mulched and either taken off site for disposal or used on site. Water Quality Improvements: The Project includes installing vegetated bioswales and detention basins to improve natural processes of water filtration and infiltration while also providing wildlife habitat. Soil will be removed and portions of the Project area will be recontoured to create bioswales and detention basins. The bioswales and detention basins will be hydroseeded with a mix of up to 14 native plant species. The removed soil will be placed within the Project area. Native Vegetation Planting: Native planting will include hydroseeding and container planting with native species, and will also include irrigation, staking, and protection from foraging. Rocks and fencing may be installed to protect these plantings from foraging and anthropogenic disturbance. A natural wood decomposing process called hügelkultur will be used to improve soil quality by helping to retain moisture in the soil. Any resprouting eucalyptus and other non-native plants will be removed using non-chemical and/or chemical weed management methods. Supplementary hydroseeding and planting may occur if deemed necessary to achieve the desired native vegetation cover. Maintenance and monitoring: Maintenance and monitoring activities will include upkeep of new plants and trees, and prevention of re-growth of eucalyptus trees and other nonnative plants. These maintenance activities may include mechanical and/or chemical methods. Upkeep of new plants and trees will involve watering and removal of stakes and guards once the plants are established. To assist with the maintenance and monitoring activities, a trail system will be established through the Project area, which will connect to an existing OVRP trail network. The public will also have access to use the trail system. Interpretive signage and benches will be installed using repurposed material from the removed trees to educate users of the importance of native plants.

San Diego

Southern California

San Diego