By Jonathan Appelbaum
As a resident of San Diego County, living with wildfire is a fact of life and is now a year-round threat. Each year, hundreds of homes are lost in California due to these mega-wildfires that are becoming the new norm. The threat of wildfire will continue to rise with our climate changing and these heat waves becoming more frequent year in and year out. As we sit here on the eve of our “traditional” fire season, we have a lot of work to do as a community! Dangerous Santa Ana winds usually pick up in October and both fire professionals and insurance companies alike agree that communities should take steps to be more prepared before the next wildfire arrives.
What does it mean to be prepared you ask? After all, if fire is a fact of life, what can people do about it? Obviously, hardening the home is the most important step a homeowner can take. Recommended measures include retrofitting attic vents, boxing eaves, screening gutters, and replacing windows and screens. Being prepared also means taking action to slow the movement of a fire. Around our homes it means properly clearing fuels and maintaining defensible space in accordance with State and local guidelines and regulations. “Not only will defensible space help slow the spread of a wildfire as it approaches a structure, but it will also give firefighters a safe place to conduct operations as they try and defend homes” says Conor Lenehan, Deputy Fire Marshal of the Rancho Santa Fe Fire Protection District.
But there is even more we can do to keep the flames at bay on a landscape level. By starving a wildfire of fuel at certain strategic points we can prevent a wildfire from traveling faster than our local fire agencies can react and deploy. Many San Diego County residents remember the Cedar Fire of 2003, the Witch Creek Fire of 2007, and the Bernardo Fire of 2014. These fires moved like freight trains pushed by ferocious winds. But what if our landscape didn’t allow that? In fact, historically it didn’t! At least not nearly so much as it does now.
What has changed? Yes, climate change plays a role, but even more so the answer is introduced plant species - Plant species brought from other parts of the world that outcompete native plants and conduct fire with embers and volatile oils that accelerate fire speed. According to experts at the California Wildfire and Forest Resilience Task Force and University of California Department of Agriculture and Natural Resources, riparian corridors, the plant communities located along rivers and streams, historically served as natural fire breaks, with the native plant species like willows, sycamores, and cottonwood trees and their high moisture contents resisting ignition. Along came the introduced (and highly flammable) plant species like giant reed, salt cedar, palm trees, and Red River eucalyptus with its volatile oils and voluminous shredded bark / kindling, changing the game. Heavily invaded riparian communities now act like fire superhighways. As research published in JSTOR online (https://daily.jstor.org/how-eucalyptus-trees-stoke-wildfires/) explains:
“The flip side of this industrial expansion of eucalypts is that these trees burn really well. Also known as gum trees, they produce gummy resin and oily leaves. The oil is what makes eucalypts toxic to most herbivores, excepting koalas... Long used for medicinal purposes, this remarkable oil has been tested in ethanol and petroleum mixtures and as a fuel in its own right. So when it comes to eucalyptus canopies, wildfires burn through them furiously; the thin, burning bark can be blown over a mile in the wind.”
Recognizing the threat these introduced species present, our challenge becomes how do we eradicate these species so that the riparian corridor can’t transport future fires so quickly into our communities?
The good news is that across the region, dozens of public agencies and non-profit partners are aligned in the battle to restore our rivers and promote safer communities. It’s a complicated, challenging task to plan these efforts, nearly impossible without collaboration and cooperation. State and Federal agencies like the USDA Natural Resource Conservation Service, US Fish and Wildlife Service, California Coastal Conservancy, and State Wildlife Conservation Board have taken turns funding these efforts. The San Dieguito River Park Joint Powers Authority (JPA) has acquired programmatic environmental clearances (i.e., CEQA) and regulatory permits (e.g. CDFW Section 1602 Streambed Alteration Agreement) authorizing the eradication of these highly flammable invasive species throughout the San Dieguito River Watershed (similarly the San Diego River Conservancy has done the same throughout the San Diego River Watershed). Meanwhile organizations like the Resource Conservation District of San Diego County and the Regional Forestry and Fire Capacity Program provide technical support for fire resilience planning and implementation for local communities throughout the County.
Which brings us to on the ground efforts in two such fire prone communities here in San Diego County, the communities of Rancho Santa Fe and Fairbanks Ranch. With the help of non-profit partners including the San Dieguito River Valley Conservancy (SDRVC) and California Native Plant Society (CNPS) several homeowners’ associations including the Rancho Santa Fe Association, Fairbanks Ranch Association, and Crosby Estates have been participating in critical fuel reduction and riparian habitat restoration efforts as far back as 2014. The Crosby Estates Habitat Management Area allowed Federally-funded work in its reach of the San Dieguito River from 2014-2016. Fairbanks Ranch and the Rancho Santa Fe Association later joined in these efforts (along with non-profit partners SDRVC and CNPS) in 2015.
The Rancho Santa Fe Fire Protection District has provided essential technical support and community outreach, and with the help of non-profit partners SDRVC and CNPS, San Diego County Parks has stepped up this work on some of its local preserves including Lusardi Creek County Park.
After years of successfully procuring small grants, gifts, and other awards to incrementally remove highly flammable invasive species from the Santa Fe Valley area (127 of 181 total acres of the riverbed and surrounding floodplain have been treated to date) the San Dieguito River Valley Conservancy successfully applied for $1.5 million dollars in funding from the State of California’s Wildlife Conservation Board in November 2023 which will allow them to target some of the last major stands of invasive species within the Santa Fe Valley for eradication.
Benefitting both local communities and native wildlife, this award will enable SDRVC and its partners to improve the resilience of the riparian forest, protect habitat for the Federally-listed as Endangered least Bell’s vireo, and protect the surrounding Rancho Santa Fe and Fairbanks Ranch communities from future wildfires.
Beginning this fall SDRVC and CNPS, working in conjunction with the Rancho Santa Fe Fire Protection District will take a giant step forward in improving the health and safety of the San Dieguito River and surrounding communities. “As a fire district, we are very excited to work with the SDRVC and CNPS on this habitat restoration project. The project will have a positive impact on the community and will reduce the fuel loading within one of our major wildfire corridors,” said Lenehan. Over three years, highly skilled field crews supervised by SDRVC and CNPS will eradicate 12.5 acres of introduced invasive species within the Rancho Santa Fe Association’s Arroyo Preserve and replace them with fire resistant native plant species, transforming the Santa Fe Valley into a safer place and higher quality wildlife habitat for future generations to enjoy.
Please any direct questions to info@sdrvc.org.
Jonathan Appelbaum is a resource ecologist.