Locally-rare plant species found in the Preserve include big-leaf maple (Acer macrophyllum), red shank (Adenostoma sparsifolium), Plummer’s baccharis (Baccharis plummerae), deergrass (Muhlenbergia rigens), whiteleaf monardella (Monardella hypoleuca), stream orchid (Epipactis gigantea), rein orchid (Piperia cooperi), Humboldt lily (Lilium humboldtii) and yellow-throated phacelia (Phacelia brachyloba). The Cold Creek Preserve includes the Canyon Preserve, Valley Preserve, West Preserve, North Preserve and old Topanga Preserve.
There are five active mitigation projects in progress in the Preserve. The “CC Voiss” project includes coast live oak replacement mitigation at a site located about halfway up Stunt Rd. The “CCDC” project involves habitat enhancement near the confluence of Dry Creek with Cold Creek, including the removal of dense colonies of common periwinkle (Vinca major) and other invasive species. “CC Argo Ditch” is a similar enhancement project that includes longer stretches of Dry Creek and Cold Creek. The “CC Baynes” project is located further downstream, with the removal of a dam abutment in Cold Creek, a large concrete pad, wood shack and tin shed all completed and revegetation of riparian and oak woodland habitat still underway. The “CC Goldin” project will involve the removal of an old Arizona crossing that is a passage barrier for potential steelhead trout migration and revegetation of riparian woodland, oak woodland and chaparral habitat. All projects involve native plantings and regular site maintenance visits to water new plantings and remove invasive species. More restoration projects are being proposed in the Cold Creek Development Plan to be submitted to the County of Los Angeles in 2016.