California’s wildlife detectives have cracked an international plant heist, sleuthing from the most curious clues — spilled dirt from mailed packages, stuffed backpacks left on ocean bluffs, a suspicious van filled with big boxes, and holes in the sand.

It’s the Golden State’s first-ever undercover plant investigation — and a tale of amazing obsession, where vigilant authorities, passionate plant lovers and an irked postal customer discovered that foreign thieves are slipping into California’s wild landscapes, fueling a budding black market in the lucrative exotic plant industry.

The suspects, Korean and Chinese nationals, face criminal charges.

And the kidnapped plants — small, squat and cherished succulents called Dudleya farinosa –– once again are back in American soil. This week, volunteers returned more than 2,000 plants to their wild and windswept Northern California coastal cliffs. Hundreds more will stay in pots, tended by other volunteers, until autumn replanting.

“These plants belong to California. They’re ours,” said an undercover agent with the state’s Department of Fish and Wildlife, the lead agency in a team that also includes the U.S. Postal Service, federal, state and East Bay parks services, California Native Plant Society, UC Santa Cruz, and local citizens.

“But it’s overwhelming,” worried the agent, who asked to remain anonymous. “How many more are we missing?”

The state’s wardens have nabbed suspects in three separate thefts along the Humboldt and Mendocino coast. There’s been one conviction; the other two cases are still pending.

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But they fear that many more plants have vanished, still unnoticed. A thriving black market in Asia means the California native plant is vulnerable wherever it grows, they say, from Oregon to the Mexican border. One variety, found in Santa Clara County, is endangered; local naturalists won’t disclose its locations, to protect it.

Investigators suspect that organized smuggling rings, based in Asia, where the stolen plants fetch up to $50 a pop, are behind the crimes. An ascending Chinese middle class, whose millions can now afford decorative plant arrangements, is fueling demand.

The plunder

At first glance, the plants — also called “bluff lettuce” or “powdery liveforever” — seem hardly worth the effort.

These blue-green blobs, with rosettes of fleshy leaves tipped in vermilion, have an oddly alien appearance. They lack the easy glamour of California’s other commonly poached species, such as abalone, sturgeon, salmon, crab, bear, antelope and elk.

But they burst into beauty when they bloom, erecting a tall stem and a candelabra-like cluster of yellow flowers.

With legions of devotees and even their own Facebook page, Dudleya have long been admired for their tenacity. Named after William Russell Dudley — the first head of Stanford’s botany department — the plant is adapted for California’s most foggy, windy and forsaken spots. It is slow growing and long-lived.

“People call them ‘charismatic,’ ” said Dudleya expert Stephen McCabe, emeritus director of research at UC Santa Cruz Arboretum who helped identify the purloined plants for state wildlife law enforcement officials.

“Sometimes you’ll see one hanging on by a little piece of root in a crack in the rock, and you think: ‘The next wind will take it,’ ” he said. “Then they’re still there the next year.”

The Dudleya community first became alarmed in 2017 when news broke of a 55-feet-long tractor-trailer rig in Baja California stuffed with 4,746 specimens of a particularly rare species, stripped from the only island where they’re found.

Then clandestine poachers came to California.

The big break

The investigation was launched after an anonymous phone call in December to Patrick Freeling, a CDFW game warden known for his diligence.

The caller, frustrated at being stuck in a long line while trying to mail a package last December in Mendocino’s tiny post office, was suspicious.

A man in line ahead of her was shipping 60 packages to China. “What are you shipping?” she asked, as the line grew, snaking out the door. “The man put his finger up to his lip and said, ‘Shhhh, something very valuable,’ ” said Freeling. “Where did you get them?” she asked. The man pointed toward the ocean.

Alerted by Freeling, U.S. Customs and Border Protection X-rayed the packages — and discovered Dudleya.

The second tip also came in by phone. Rushing to the cliffs near Point Arena, Freeling recognized the suspect from the post office’s video surveillance. The man carried 50 Dudleya in his backpack.

Uh oh, thought Freeling. “This is going to be the new thing,” he warned other coastal wardens.

The next tip was a suspicious minivan parked on Highway 1 along the Mendocino coast, loaded with boxes. Suspecting its driver was an abalone poacher, Freeling crawled through the dense underbrush toward two large backpacks, left on the bluffs. Poking them, he felt something else: Dudleya.

The suspected crooks

The suspects spoke no English and carried Korean passports. Back at their van — rented at San Francisco International Airport and headed to Los Angeles — Freeling found 850 more plants and 1,450 smaller “rosettes.”

“It is my belief that they were picking plants, filling boxes, filling the van and shipping them as they moved south down the coast,” said Freeling. “They had numerous contacts for succulent dealers in California and abroad.”

Savvy U.S. Customs and U.S. Postal Service workers were behind the most recent bust on April 4. One opened a box from Humboldt County — labeled “spokes” — and reported the plants to CDFW. Another noticed dirt falling out of boxes. Yet another, passionate about succulents since childhood, found and shared the sender’s address. Surveillance began.

Wildlife officers pulled over the suspects’ van, rented at the Las Vegas airport, then made arrests and seized 1,334 plants — all on their way to being shipped overseas.

Then, armed with a search warrant, they raided the suspects’ cabin among the redwoods at the cheap and threadbare Ocean Grove Lodge in Trinidad. Authorities found another 1,000 Dudleya there.

“I walked into the room and saw a tarp on the ground, with tons of plants on it,” said the CDFW undercover investigator. “There’s this anxious feeling. You’re thinking, ‘How bad is this?’ ”

Three men — Taehun Kim, 52, and Taeyun Kim, 46, both of Korea, and Liu Fengxia, 37, of China — were booked into Humboldt County Jail. They’ll be arraigned on May 16.

The consequences

The tragedy of poaching is not just the pock marks left across the cliffs, said McCabe. Or the damage done when thieves scramble across a delicate landscape, like children on an Easter egg hunt. Or the broken link in the food chain for insects and birds, and the loss of nature’s complexity.

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It’s the pointless death of the plants — in capture, transit or after sale — that most distresses him. If boxed in damp darkness or overwatered, a Dudleya’s roots rot. It turns into brown mush.

“They are tough as nails in exactly the right spot,” McCabe said. “But many times the collected plants just die.”

Nancy Morin, president of the Point Arena-based chapter of the California Native Plant Society, which is offering foster care to hundreds of plants until autumn, called it “a punch in the gut. It’s astonishing. Horrifying.”

The theft and illegal trade of individual plants is a longstanding problem: Bay Area homeowners sometimes wake to find divots where there once were succulents, and the federal government electronically tags thousands of cacti in Saguaro National Park. But the audacity of the recent thefts is unprecedented.

The investigations will continue, as new tips arrive, said Patrick Foy of CDFW.

“Once it hit our radar screen, and we looked more for it, we discovered that it’s bigger than we thought,” he said.

Eventually, the thieves will be sent back to Asia. But — this time — the Dudleya are staying in California.

Have a tip about poaching?

Anyone who believes they are witness to unlawful poaching or pollution activity is encouraged to call CalTIP, CDFW’s confidential secret witness program, at (888) 334-2258 or send a text to tip411. Both methods allow the public to provide wildlife officers with information to assist with investigations. Callers may remain anonymous, if desired, and a reward can result from successful capture and prosecution.