Rather than focusing on the potential damage that could occur at the Arroyo Hondo Preserve this coming rainy season, the Land Trust for Santa Barbara County is focusing more on the opportunities that the Alisal Fire offers.
“We need to start talking about the role that open space plays in a fire-adapted climate and as a buffer around communities in the county,” executive director Meredith Hendricks told reporters invited to see the wildfire impacts firsthand.
Noting that fire has been so much a part of our lives in recent years Hendricks explained, “This is an important opportunity for Arroyo Hondo to play a major role in helping better understand how fire recovery occurs and help educate our visitors and students around the county about fire ecology.”
Taking the Lead in Fire Studies
Currently, Sally Isaacson, the Land Trust education coordinator, is in the process of developing a fire ecology program to provide online resources about fire as well as programs designed for docent tours at the preserve on the Gaviota coast west of Refugio State Beach.
“Isaacson is already in the process of identifying photo points and stations throughout the preserve that will experience change as a result of fire,” Hendricks noted. “Over the next two, three years we want to follow the changes occur in the preserve and share those experiences with the public.”
One of these is to learn more about how oak trees respond to fire.
“Arroyo Hondo is part of a watershed in which 93% burned,” Hendricks added, explaining that while most of the riparian areas in the main canyon survived relatively well, the oaks on the hillsides and on the ridges have taken a major hit.
Along with Isaacson, preserve ranch manager John Warner is in the process of setting up a series of transects designed to study the impacts of the fire and how things respond to it.
A major part of his work will be to see how fire recovery occurs in a canyon like Arroyo Hondo. As co-owner of Santa Barbara Natives, Warner has been involved in providing native plants for restoration projects throughout the South Coast for more than 15 years. His expertise will be extremely helpful in this effort.
Along with the transects, Warner is working with Ethan Turpin’s nonprofit organization, The Burn Cycle Project, to begin setting up cameras designed to provide time-lapse photography of the recovery. This should be very helpful in providing the detailed visual data that allows one to see how things change over time in various parts of the preserve.
Testing Restoration Techniques
Warner is also working with the California Coastal Conservancy (CCC) and Cuyama Lamb, a sheep outfit that uses sheep to reduce fuel loading.
The preserve recently received a $24,000 grant from the CCC for use of the sheep to graze the hillside nearest to the historic adobe. Warner credits the work for saving the adobe and allowing firefighters to focus on protecting other more vulnerable areas.
“The sheep did a really great job,” Warner said. “The way Cuyama Lamb moves the sheep from area to area, allowing them to graze intensely for short periods of time mimics nature.”
Along with fire mitigation, Warner is looking to see how effective the sheep can be in helping convert some of the areas nearest Highway 101 from non-native and highly flammable vegetation like mustard and annual grasses.
Running parallel to the western portion of the Gaviota coast, several of the geologic layers play an important role in coastal restoration efforts.
“The soil type that’s close to the freeway is Monterey shale, which should come back just fine,” Warner told me.
Adjacent to the Monterey shale is another shale, one more prone to erosion called Rincon shale.
This type of shale forms the rolling grass and mustard cover along the north side of Highway 101. Ironically, though a striking contrast to the jagged upthrust sandstone layers above it, the shale is mostly all clay and particularly welcoming to the non-natives.
Right now Warner is looking at the possibility of reintroducing native plants on the Rincon soils, using the sheep to help weed out the non-natives.
“The sheep act a bit like a herd of deer do,” Warner explained. “They are always eating everything for a bit and then moving to a different place rather than overgrazing it.”
Warner notes that along with the transects he has put together four different study plots on four different hills within the Rincon shale soils. He is hoping to see whether the natives will flourish or not.
Risks to the Preserve
The Alisal Fire ignited the afternoon of Oct. 11 between Alisal Lake in the Santa Ynez Valley and West Camino Cielo. Within a few hours, the wind-whipped fire had burned over the mountain and all the way to Highway 101.
The fire charred 16,970 acres — 26 square miles — before it was fully contained weeks later. The cause has not yet been determined.
Given the immensity of the amount of Arroyo Hondo watershed that burned, the potential for change is immense, not only incrementally as the vegetation recovers but catastrophically as well.
“Everything at Arroyo Hondo is steep on all sides” Warner explained, comparing the terrain to Montecito, the site of deadly flash flooding and debris flows following the December 2017 Thomas Fire.
“In Montecito, you only had steep on one side. We have steep on three sides.”
The recently released report conducted by the U.S. Forest Service BAER Team is predicting a 33% probability that the Gaviota area will experience a 1.72” storm that will last 5.32 hours with .61” of storm runoff.
This type of storm could create major debris flows in Arroyo Hondo and Arroyo Quemado canyons, both of which suffered major loss of vegetation.
“Given the large percentage of moderate soil burn severity on steep slopes within the western half of the Alisal Fire,” the BAER Report notes that “watershed response will be moderate to high across these burned catchments, with the greatest responses anticipated in the Arroyo Hondo, and Arroyo Quemado catchments.”
Hydrologists expect hill slopes in Arroyo Hondo Canyon to average 3,360 cubic yards per square mile of what they term “sediment potential.” At Arroyo Hondo, with a watershed in the neighborhood of four square miles, that works out to something over 12,000 cubic yards of material, enough to create a catastrophic debris flow under the worst of conditions.
“The risk for that type of flow is huge,” said Warner, who has been assessing the damage. “If the storm is big enough it’ll take all the trees in the creek with it, plug up the tunnel beneath Highway 101 and flood the entire area.”
Given a storm similar to what El Capitán Canyon experienced in January 2017 after the Sherpa Fire, it is possible Highway 101 could be compromised as well.
Open Space Role on the Gaviota Coast
One of the hallmark traits of the Land Trust for Santa Barbara County is the fact that it is a conservation organization rather than an advocacy organization.
“We work with willing landowners,” Hendricks said, “but when we do so we promote policies that help conserve both natural resources and agricultural lands in a way that creates win-win situations.”
Along with these goals, it appears that it may add another important benefit to its portfolio.
“We need to start looking at how open space can play a vital role in supporting community resilience, reinforcing their value as buffers around the more fire-prone parts of our communities,” she said.
Given the extreme loss of vegetation and soil damage, there may not be another opportunity to learn how an entire watershed recovers from a wildfire over the next few years.
Look for the Land Trust to take the lead in this effort.
— Noozhawk outdoor writer Ray Ford can be reached at rford@noozhawk.com. Click here for his website, SBoutdoors.com. Follow him on Twitter: @riveray. Connect with Noozhawk on Facebook.