That’s Amole

Nature is nothing if not surprising. CNPS botanists recently relearned this timeless truth this spring in San Luis Obispo County, where they gathered data on an expansive, newly identified population of Camatta Canyon amole (Hooveria purpurea var. reducta). The plant, which is listed federally as a threatened plant and as a rare plant at the state level, had long been thought confined to one tiny population in the center of the county. There, at the intersection of Highway 58 and a U.S. Forest Service throughway known as Red Hill Road, the tiny flowering lily relative enjoyed a reasonably safe, quiet life in a semi-protected setting.  

That perception changed dramatically in April, when a crew of researchers from CNPS’s Rare Plant and Vegetation programs documented tens of thousands more Camatta Canyon amole plants than previously known at Las Piletas Ranch. Acquired by The Nature Conservancy in 2022, the ranch was already well known to conservationists for protecting more than 13,000 acres of habitat for birds, pronghorn, tule elk, and other migratory species in central SLO County. The ranch’s Camatta Canyon amole population—roughly 13 miles southeast of the small population on Highway 58—signals both an eye-popping find by CNPS botanists and a burst of gratifying good news about native plants. Here, across 187 acres of conserved vernal pool habitat, was a rare species hiding everywhere in plain sight. 

“There are big successes and lots of great data coming out of this collaboration with The Nature Conservancy,” says Kristen Nelson, Rare Plant program manager with CNPS. “It’s a large, conserved property in an under-documented area. Then, a federally threatened species is found there—and it turns out to be a much bigger population than we originally gauged.”

The first hints that the rare amole occurs at the ranch arrived in 2024, when The Nature Conservancy enlisted CNPS to gather vegetation data for mapping. Botanists reported prominent but limited instances of the amole, with the recommendation to follow up the research on a later visit. In 2025, when Nelson arrived at the ranch for fieldwork, she didn’t have to look far for the amole. “We found it within 10 feet of the car, probably,” she says. “We realized, ‘Oh, there’s a plant here. There are a few plants here. OK, there are a lot of plants here.”

Along with fellow rare plant botanist Sharon Estrada, Nelson excitedly but rigorously spent the next five days observing thousands of the plants. (“You have to be scanning and actively using your brain,” Nelson says. “You can’t be thinking about your dinner plans.”) They found the specimens principally clustered in patterns where water had gathered around vernal pools and mima mounds, which appear in low, rolling, grassy clusters across the landscape. The Nature Conservancy (TNC) had passed along aerial data showing locations where this specialized habitat occurs, a total of 187 acres where TNC’s own researchers sought further information. Nelson immediately sent photos and text messages to her TNC contacts about the magnitude of the find. “We saw it, and then we saw more of it,” Estrada recalls. “And we were trying to figure out on the fly how the two of us would map this big population.” 

But the true scale of the diminutive plant’s presence at Las Piletas Ranch didn’t become fully evident until this spring, when Nelson and Estrada returned with three other CNPS botanists. Equipped with a more fully developed survey plan—and in a banner year for this and other bulb-forming species—the team documented the population as tens of thousands of plants. Nelson sent photos and text messages of the amole population to partners at TNC. “The discovery of potentially the largest population of a rare plant anywhere in the world is extremely exciting from a conservation perspective,” says Dr. Scott Butterfield, lead scientist with the land program at TNC. “It also brings with it a responsibility to understand more about why it’s there at such high levels—and why not at such high levels elsewhere—and how we can manage the landscape to protect those populations and potentially grow them bigger.” 

Additionally, Butterfield says, the amole mapping can substantially support TNC’s burgeoning efforts at Las Piletas Ranch. Knowing the location and the size of the population can help define its prospective role in assisted migrations, reintroductions, and translocations for plant and animal species alike. A “virtual fencing” pilot project at the ranch—where electronic collars guide the 350 resident cattle away from sensitive vegetation—can use the amole findings to keep the plant safe from wayward grazing. “We’re focused on outreach with grazing and conservation partners across the state,” Butterfield adds. “There is so much to learn about how we use a new technology like virtual fencing to support conservation goals for rare plants.”

Nelson speculates that the amole population has likely been at the Las Piletas site as long as the species has existed in California. It just wasn’t documented until recently because of the ranch’s transition from private ownership to conservancy. How the amoles got there, or why so many, or why they’re separated from the only other known population to the north, is anyone’s guess. (Nelson theorizes that birds likely played a role.) Meanwhile, hoping to capture as much of the Camatta Canyon amole’s genetic diversity as possible, Nelson and the CNPS team have seed-banked the newly identified population from the ranch. 

As nature’s surprises go, this is one with a happy ending—and a bright future. “Ultimately,” Butterfield says, “we would like to see our work at Las Piletas lead to a greater understanding of these amole populations and the management efforts needed to protect and expand them, leading to recovery.”