As Nevada County law enforcement officers look toward a busy marijuana harvest season this fall, counterparts further south - where the harvest starts earlier - already are in action.
Plantations operated by several Mexican cartels have been raided in the central Sierra Nevada foothills in the last three weeks, leading to the arrest of 97 people, destruction of more than 432,000 plants and seizure of more than $1.7 billion in pot, federal and state agents told the Associated Press Thursday.
Most of those arrested are Mexican nationals, Fresno County Sheriff Margaret Mims told the AP. Agents were combing tracts of public land in the remote stretches of Fresno, Madera and Tulare counties.
In Nevada County, "I think it's going to be a busy, busy year for our (Narcotics) Task Force," Sheriff Keith Royal said. "Historically, there are tens of thousands of plants out there" in cartel plantations locally, in addition to commercial farms operated by county residents.
Mexican drug cartels tend to grow their crops on remote public land and on private properties without the knowledge of absentee owners, Royal said. About a month ago, a cartel operation was spotted in Mystic Canyon near Truckee, and growers moved about 1,000 plants to protect them from seizure, he added.
In the central Sierra Nevada, warmer, drier weather leads to earlier harvests there; in Nevada County, agents expect the harvest to peak in mid-August through the first of October, Royal said.
But Nevada County's more abundant water supplies offer an advantage offsetting later harvest: Higher quality.
"I hate to say it, but it's a reality, because water sources are readily available," Royal said. In the central Sierra, "to make up for (lesser quality), they have sheer volume."
Noncartel commercial operations also abound in western Nevada County and are starting to harvest, but Royal did not have an estimate about their size.
Last week near Rough and Ready, agents seized 2,804 marijuana plants in various stages of growth in a major cloning and growing operation.
They also seized about $5,000 in cash in a house and about 200 pounds of untrimmed marijuana.
Seven people were arrested in that raid, all Rough and Ready or Penn Valley residents.
As outdoor marijuana farms mature and become more obvious from the air - agents say the particular green of cannabis is unmistakable - "then we will focus our attention on those operations," Royal said.
In the central Sierra sweeps, about 450 local and federal agents have been involved in the operation that ends today, said Gil Kerlikowske, who directs the White House's Office of National Drug Control Policy and was in Fresno on Thursday to support the raids in the region.
"Tremendous devastation has been done and continues to be done by these industrial-sized grows," Kerlikowske told the AP. "When people see what these marijuana grows do to their land, it makes a huge difference."
Still, according to U.S. Drug Enforcement Administration statistics, that accounts for a small percentage of the pot typically seized in California each year.
Federal prosecutors were taking a more aggressive enforcement tack this year and charging those arrested in the bust with crimes including criminal immigration offenses, conspiracy to distribute marijuana and depredation of public lands, Eastern District of California U.S. Attorney Benjamin Wagner told the AP.
Officials would not clarify which Mexican cartels were involved, but said more arrests were pending.
Associated Press writer Garance Burke contributed to this story. To contact City Editor Trina Kleist, e-mail email@example.com or call (530) 477-4230.