
There are hundreds of acres of habitat restoration projects currently underway across the Irvine Ranch Natural Landmarks. Restoring native habitat at a large scale is a challenge but is the most effective means of improving long-term habitat health in areas overrun by weeds. Many different landowners and partner groups perform habitat restoration projects, and there are many opportunities for the public to get involved. On behalf of landowners such as OC Parks, City of Irvine and City of Newport Beach, as well as agencies such as Orange County Transportation Authority, Irvine Ranch Conservancy currently manages nearly 200 acres of active habitat restoration, ranging in intensity from sites that need two years of site preparation, seeding, transplanting and site maintenance to sites with some existing native vegetation that just need weed control. Here are details for some of those projects:

Bee Flat Canyon covers almost 300 acres within Limestone Canyon, and in progress are 84 acres of restoration. In addition, five weed species are being targeted for removal across the entire canyon. While several different habitat types are being restored, oak woodland is one of the most visible components.
Buck Gully Reserve is a 300-acre urban wildland in Newport Beach which hosts monthly public volunteer events to remove invasive plants and replant natives. The project includes a 1-acre native plant demonstration area developed in partnership with the City of Newport Beach Water Wise program, giving visitors and nearby homeowners a preview of native habitat reconstruction that meets fire codes in fuel management areas.
Lower Silverado Canyon restoration project encompasses the Silverado creek bed and adjacent upland sites in OC Parks’ Black Star Canyon. This area is dominated by non-native annual grasses as well as several highly invasive plants, such as perennial pepperweed. These areas are being restored to re-establish and enhance native riparian habitat for wildlife.

West Loma Ridge is an expansive area split by the 241 toll road that is mostly overrun by non-native grasses and black mustard. The hills and slopes are being restored to native grassland, coastal sage scrub, and elderberry shrubland; gullies will be restored as riparian corridors. The project area is on Loma Ridge near the Hangman’s Monument and includes support and collaboration from several agencies, including UC Irvine, the Nature reserve of Orange County, TNC, Orange County Parks and the Orange County Transportation Authority. Fencing modifications and habitat enhancements near a wildlife undercrossing will also improve the connection between the sites for wildlife.
Quail Hill is 733 acres of former ranchland that is now permanently-protected open space in Irvine. After the cattle left the hills, invasive artichoke thistle (Cynara cardunculus) and other weeds to thrive. As a result of volunteer efforts, the artichoke thistle has dramatically decreased and native plants have been introduced. Volunteers stay vigilant against these weeds to help the native plants thrive.