Coif Your Canyon to Reduce Erosion and Flammability
By Judy Beust Harrington, Co-Chair, Kensington Fire Safe
Photo Credit (Above): Lucy Warren
This column is your fire safe council’s effort to share answers to questions we get from community members. Send your fire-related questions to info@kensingtonfiresafe.org and we’ll do our best to find the answer!
Q: From Loren, an Alder Circle resident: “What should I plant in my shaded, bare dirt canyon area, to reduce fire and erosion risk?”
A: There was a house on Alder they called the sliding shame… I’m told the back room went right down the canyon decades ago in a heavy rain, probably like ones we witnessed this past winter. This neighbor’s question is timely!
Lists of online drought and fire-resistant plants seem overwhelming, so I reached out to Kensington resident and UC Cooperative Extension Master Gardener, DeLayne Harmon, and she reached out to fellow MGer, Lucy Warren, a southern California sustainable landscaping expert and writer. (Check out her excellent “California Native Plants” video at: https://www.youtube.com/watch?v=6K_0mj4h548.)
Lucy’s advice? “My personal one-plant response for slopes: Baccharis ‘Pigeon Point’ mixed with at least four other species.”
“Coyote Bush” – as it is also called – is a favorite of your fire safe council! Not only is it fast-growing, drought-tolerant and slope-stabilizing, it also is said to emit a mild flame retardant when faced with a fire. And, while it prefers sun, it can grow in mostly shade too.
DeLayne clarified that Pigeon Point ground cover – Baccharis pilularis spp pilularis – is a specific coyote bush hybrid with smaller leaves that only grows to about two feet. You can often find it at City Farmers Nursery (3110 Euclid) or Hunter’s Nursery (3110 Sweetwater Road, Lemon Grove). More info at Calscape.org: https://calscape.org/Baccharis-pilularis-ssp.-pilularis-‘Pigeon-Point’-(Pigeon-Point-Coyote-Brush)?srchcr=sc5e39ba57165f9
Be a Diversity Diva
What about that “four other species” advice? Check out Lucy’s co-author and popular local landscaper, Greg Rubin’s website on the role of native landscaping in fire suppression. Greg has landscaped homes that came out relatively unharmed while nearby houses were destroyed in wildfires. His years of research for the U.S Navy established that lightly hydrated evergreen, perennial native plants assist in fire suppression as well or better than succulent plants. And diversity can help fight diseases too. More info at Greg’s CalOwn website: https://www.calown.com/nativeEcology_fireSafety.html
The local chapter of the California Native Plant Society (https://www.cnpssd.org/ ) has a great pamphlet which lists native plants for area landscapes. And you can narrow info down to your specific needs at gardenplanner.calscape.org.
Plant water!
Another way you might increase your canyon’s erosion and fire resistance is to capture some of the mountains of water that run off your house, with rain barrels and “swales” to safely catch the barrel’s overflow during our rainy season. Swales are basically flat ditches or gutters, which can be filled with rocks, compost, and plants to safely increase your ground water and keep established plants healthy. They can slow a fire’s spread toward your house and keep your trees alive if the day ever comes when we’re prohibited from using scarce water for gardens. Much swale how-to info is available online or search permaculturenew.org for “mini-swales in an urban backyard.” (https://www.permaculturenews.org/2016/01/11/mini-swales-in-an-urban-backyard/).
Bottom line for fire and erosion resistance: no to any dry woody stems, like ice plant, no to invasives like Pampas grass or leaving the ground bare. Yes to harvesting barrels of rainfall to support oodles of attractive native plant diversity! Matchy-matchy is out in jewelry and gardens!