An all-day raid Thursday resulted in the seizure of thousands of marijuana plants by regional law enforcement in the Pioneer area. Photo by: Courtesy to the Ledger Dispatch Regional law enforcement officials had to navigate harsh terrain to locate abandoned camp sites thought to have housed cultivators of a marijuana operation in Pioneer. Photo by: Courtesy to the Ledger Dispatch

With the early morning sun piercing through the steep, wooded Mokelumne River canyon, dozens of regional and federal law enforcement officials descended on two large scale marijuana operations Thursday in the Pioneer area.

The two sites, which together stretched more than a mile through numerous draws and uneven, rugged terrain, were reportedly separate operations tended by different means. The larger operation, which saw roughly 1,000 marijuana plants located in spread-out, remote locations of the forest, was being watered by an irrigation system. Evidence at this site suggested the cultivators were not camped at that operation and only periodically tended to it.

The smaller site, however, showed recent signs of human activity. Investigative teams found two camp sites marked by camouflage tents, one day camp, two processing sites and evidence indicating that the cultivators were armed.

No suspects were located. In all, 12,330 mature marijuana plants were located, valued at approximately $5 million.

"I believe this is the largest grow we've done in the almost 18 years I've been here," said Amador CountyUndersheriff Jim Wegner.

"This, however, is not uncommon in many other counties." Both Calaveras and El Dorado counties regularly seize gardens of this size, Wegner added. One of the reasons, he surmised, is that both counties have more remote federal land than Amador County. Amador's rural areas are also more heavily populated.

This marks the first marijuana eradication operation this year in the county. The illegal operation, which was on public land, was surveilled a couple of weeks ago. On Thursday morning, the sites were cleared by SWAT teams from Amador, El Dorado and Calaveras counties, who approached from different points at first light, searching the tumbling canyons and spider-leg trails for signs of life. The operation was a logistic challenge, Wegner said, with teams of SWAT personnel having to follow every water line that split off from the main trail.

Wegner said it was roughly noon on a scorching day before the teams finished searching the area for suspects and booby traps, none of which was found.

Law enforcement officials then spent the next four hours scouring the thick, forested terrain for evidence and to uproot the illegal plants. The Amador County Sheriff's Office led the operation, receiving aid from the California Department of Justice, U.S. Bureau of Land Management and a Jackson police officer.

Investigators found five gardens overall, four of which belonged to the main operation and were scattered throughout the teeming mountainside in small pockets of a few plants. The other site was located near the Tiger Creek reservoir, marked by neat rows of hand-watered plants.

While this was likely the largest operation Amador County has seen in the past decade, Wegner said the prevalence of large marijuana grows like these has been increasing in the past few years.

The investigation into these two sites is continuing pending the processing of physical evidence located at the scenes.