Three men were charged Friday with trying to smuggle thousands of California succulents to South Korea, the U.S. Department of Justice said.

The South Korean nationals pulled the live Dudleya succulents out of the ground at remote state parks in Northern California in 2018, took them to a nursery in San Diego and then transported the plants to a commercial exporter in Compton with the intention of using a fraudulently obtained certificate to ship the plants to South Korea, prosecutors say.

Law enforcement seized around 3,715 Dudleya plants worth $600,000, the DOJ said.

Byungsu Kim, 44, who operated the nursery in Vista, Youngin Back, 45, and Bong Jun Kim, 44, were arrested in Compton last year and face state criminal charges, according to the DOJ.

Back and Byungsu Kim have since fled the United States and are fugitives, authorities said.

The unique succulents are valuable in parts of Asia, and because they take a long time to grow, smugglers are known to harvest them from the ground in California and export them to be sold on the black market, authorities said.

The overseas market value of Dudley succulents is between $40 to $50 per plant, according to California wildlife officials.

Smuggling the Dudleya plants, also known as “live-forevers,” has become common, according to U.S. Fish and Wildlife officials who say the plant is “hanging by a thread.”

The ravaging wildfires in California nearly wiped out the succulents, and what remains of them in the cliffs and mountains, now faces a new threat from poachers who hope to make money from the illegal trade, officials said.

Wildlife authorities at the Santa Monica Mountains say they often find clumps of the plant on trails, and it usually indicates that someone had been pulling them out of the ground.

There has been evidence of Dudleya plant poaching in Southern California for decades, but it has gotten worse in recent years, U.S. Fish and Wildlife said.

After a different seizure last year, 2,000 Dudleya succulents that were on their way to China and South Korea were replanted in the Mendocino and Humboldt county cliffs, according to the California Department of Fish and Wildlife.

There were so many to return that wildlife officials put out a call for volunteer botanists to help replant the succulents, which are sensitive and need a specific environment to thrive.

After an April 2018 investigation, officers found $90,000 worth of the plant in a man’s hotel room. They had been ripped out of the ground in Humbold County to be sold in Japan, China and South Korea, the agency said.

“The removal of Dudleya can result in environmental degradation of habitat and a destabilization of bluffs and cliffs on the coastline,” Fish and Wildlife said, calling the poaching trend “alarming.”

Many types of Dudleya are listed as endangered or threatened, and pulling them out is a state and federal crime.

Byungsu and Bong Jun Kim, and Back were all charged in a two-count indictment with conspiracy to knowingly export plants from the United States that had been taken in violation of California law, and attempting to export plants taken in violation of state law, the DOJ said.

They face a statutory maximum sentence of 10 years in federal prison if convicted as charged.