The Leona Quarry project, in Oakland, California, was in operation as a rock quarry through the 1980's. Quarrying activities severely altered the 128-acre site's topography, soils and vegetation and left a large scar on the landscape with steep denuded slopes with elevation differences of up to 800 feet. Successful restoration of this highly degraded site to native coastal sage scrub, chaparral, and oak woodland habitat presented many challenges. H. T. Harvey & Associates designed and implemented a pilot revegetation site within the project area to test a number of assumptions. Soil amendments, irrigation regimes, and foliage protection measures were tested for 3 years prior to developing the final revegetation plan for the remainder of the site. The pilot site provided invaluable information for determining the final planting palette, planting layout, and soil amendment protocol. H. T. Harvey & Associates completed the final revegetation plan for the site in 2004. Mass grading of the site was completed in 2004-2005. The site's infertile, compacted soil conditions were overcome through a combination of site preparation methods. Planting holes were augered and backfilled with amended soil on cut slopes, while surficial soil amendments were incorporated across the fill slopes. A total of 6078 plants were installed across approximately 40 acres in randomly shaped polygons to increase edge habitat to benefit the Alameda Whipsnake and other native species. Year-1 monitoring results showed that plant survival is very high at 91%. On-going cover and survival monitoring will continue to provide new insights to the success of the project.
