The latest figures show that local, state and federal law enforcement agencies are on track to eradicate an estimated 1.5 million plants from outdoor gardens – mostly on public land – down from a decade high of about 7.3 million plants in 2009. This year's seizures would be the lowest since 2004, when a little more than 1.1 million plants were eradicated, according to Drug Enforcement Administration statistics.
Some attribute the drop to a federal crackdown on medical marijuana dispensaries and illegal grows on public land and political losses in California, such as voters' defeat in 2010 of the pro-legalization Proposition 19. At the same time, fewer counter-narcotics teams hunted for California pot this year due to the elimination of a three-decades-old state eradication program.
Others say growers have retreated to smaller garden plots on private land and gone back underground to wait out what legalization advocates have deemed the last throes of prohibition. They also point to a glut of marijuana that depressed wholesale prices and burst the state's so-called "Green Rush" to capitalize on the relaxed attitudes toward the drug.
Tommy LaNier, director of the National Marijuana Initiative, a program funded by the White House Office of National Drug Control Policy, said law enforcement officers and agents had a hard time locating grows this season, even though they spent the same amount of flight time as in years past searching for plants.
Fewer plants also have been taken out of Oregon and Washington, two states that also have seen large numbers of illicit gardens in past years.
"There's a significant downtrend in cultivation activities," LaNier said. "There's been a huge impact because of what we've been doing the last six years. We've come a long way."
A confluence of other factors might have contributed to fewer plants this year, including weather, improved intelligence gathering and investigative efforts, more tips about illicit marijuana gardens from the public, and concerted efforts to prosecute growers, which didn't occur five or six years ago, LaNier said.
LaNier also highlighted the use of intelligence analysts and informants to target marijuana gardens on public land. The U.S. intelligence community has helped track money that moves across the southern border and people who are entering the United States from Mexico who are involved in cultivation, he said.
Lawmakers in Washington have turned their attention to marijuana being grown on public land by foreign nationals. U.S. Sen. Dianne Feinstein, D-Calif., chairwoman of the Senate Select Committee on Intelligence and co-chairwoman of the Senate drug caucus, held a hearing on the issue last year, while U.S. Rep. Mike Thompson, D-Calif., who sits on the House intelligence committee, pushed for more involvement and coordination from the director of national intelligence and other intelligence agencies.
While more federal attention has turned toward California's outdoor pot industry, the state's 28-year-old Campaign Against Marijuana Planting did not operate this year after funding was slashed last year. Gov. Jerry Brown effectively shuttered the state Department of Justice's Bureau of Narcotic Enforcement, which oversaw the program and eradication teams in five regions in the state.
In the absence of state funding, a consortium of federal agencies, led by the DEA, banded together to support three units of the Cannabis Eradication and Reclamation Team, as the new program is known. State Department of Justice spokeswoman Michelle Gregory said that as of last week, the eradication and reclamation teams, which focus on both destruction of illicit gardens and environmental cleanup, this year have destroyed 959,144 plants from 215 sites, more than half of which were found on national forestland.
Dale Gieringer, the California coordinator of the National Organization for the Reform of Marijuana Laws, which has titled its annual conference next month in Los Angeles "The Final Days of Prohibition," said that other than a brief period in the late 1980s and early 1990s, the annual eradication campaign didn't have a huge impact on marijuana production. The same might be true for recent efforts, he said.
He said growers have improved their techniques to avoid detection, with some turning to smaller patches and even using Google Earth as a tool to help improve concealment.
"All I can look at are prices and availability on the ground, and I really haven't seen any impact," he said.
Kym Kemp, a blogger and radio host who follows the Humboldt County marijuana scene, said gardens are getting larger in her area.
But there still have been big busts this year, including a multi-agency operation dubbed Mountain Sweep, which netted more than a 1 million plants in seven Western states. The DEA estimated the value of the seized marijuana was more than $1.45 billion, according to the U.S. attorney's office in Sacramento. About two-thirds of those plants were found on public land, including more than 500,000 in California.
As law enforcement has squeezed growers on public land, officials have seen them migrate elsewhere, often to where they can exploit the state's permissive medical marijuana law, officials said.
"There is other stuff that is happening," said William Ruzzamenti, who directs the federally funded Central Valley High Intensity Drug Trafficking Area. "My honest opinion is that there was just as much growing this year as last year. But we're just not getting it."
Increasingly, growers are moving out of state, to places like Nevada, southern Utah, Wisconsin and North Carolina, often growing closer to drug markets, he said.
In California, Ruzzamenti said there's been a transition from illicit gardens on public land in the Sierra Nevadas to the valley floor in Fresno and Tulare counties to even more remote plots on private land in Northern California, where growers operate "under the pretenses of medical marijuana."
"In Trinity and Siskiyou (counties), the situation is just ridiculous," he said.
For years, Trinity County, Humboldt County's eastern neighbor, has attracted growers from around the country with its sparse population and amenable climate.
But local law enforcement says the region has seen a recent explosion in marijuana gardens on private land, as growers have moved off public land. Many cite Prop. 215, the 1996 voter-approved law that allows marijuana cultivation and use for medical purposes.
"The number of private grows we have is astronomical. It's a huge problem," said Chris Compton, a detective with the Trinity County Sheriff's Department. "It's not a secret what we have going up here."
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