Revisiting a Rare Plant Population Just in Time

By David Magney

After conducting a rare plant survey near Santa Ynez in June of 2016, I took the opportunity to revisit several of the occurrences of Arctostaphylos refugioensis, Refugio Manzanita. This species is classified as a rare plant, assigned to the CNPS California Rare Plant Rank 1B.2.

Arctostaphylos refugioenesis
Arctostaphylos refugioenesis – photos by David Magney

A plate from Field Guide to Manzanitas
A. refugionensis plate from Field Guide to Manzanitas by Backcountry Press (2015).

There are only 5 known occurrences, all of them at the upper end of Refugio Canyon and an adjacent ridge top in the Santa Ynez Mountains. Before my visit, there had been no recent reports for CNPS or the California Department of Fish and Wildlife’s Natural Diversity Database (CNDDB) in over 20 years. So, needless to say, I decided to see how they were doing. I had last seen this species on a Botany class field trip taught by the late UCSB Professor J.R. (Bob) Haller. That was back in the early 1980s.

Populations of Arctostaphylos refugioensis are accessible along Refugio Canyon Road, from U.S. 101 to the south. Most of the plants grow on private property in Refugio Canyon, with the rest within the land administered by the Los Padres National Forest.

Happily, I found five healthy occurrences of Arctostaphylos refugioensis. I then photographed many of the plants and filled out a CNDDB Field Survey form. This allowed CNPS and the CNDDB to update the occurrence records for this rare shrub. While it is a priority for our Rare Plant Rescue project, another partner had planned to seed bank this species and so, unfortunately, I did not collect seeds during my visit.

Just one week later the Sherpa fire started in Refugio Canyon, burning much of the canyon and habitats to the east and northeast. How many of the Arctostaphylos refugioensis populations were affected is unknown as access to the canyon has been restricted only to residents. I will go back soon to see how the occurrences were affected. Our hope is that, even if the shrubs were consumed by the fire, they will return from seed and that some of those seeds can be banked as insurance against future disaster.

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