The number of marijuana plants eradicated from California's 18 national forests is up this year following three consecutive years of decline.
Law enforcement has so far removed 989,277 plants from the Pacific Southeast region, up from 811,163 plants last year, said John Heil, spokesman for the U.S. Forest Service's Pacific Southwest Region. The region includes California and a tiny portion of Oregon and Nevada.
California is responsible for most of the marijuana found growing in national forests nationwide, Heil said. Of 970,094 plants seized in federal forests last year, 838,358 were in California, he said.
Eradication figures by forest were not available.
The number of pot plants seized to date on private and state lands in California also were not available Friday.
While the numbers are up, this year's marijuana yield is so far well below the 2009 peak, when more than 3.6 million plants were seized in California's federal forests.
There are a number of different theories for the rises and declines in the annual plant counts.
In the years leading up to the 2009 peak, there were more available resources, including officers, and there were increases in concerted, multi-agency efforts to combat pot production, Heil said. That not only increased the number of plants seized that year, it may have led to the declines in subsequent years.
"We recognize some (pot growers) will have moved" out of the forests and onto private lands, Heil said.
Some growers also may have been discouraged by recent efforts to remove their infrastructure, including water pipes and chemicals, said Mike Johnson, commander of the state Department of Justice's Campaign Against Marijuana Planting. CAMP is a multi-agency task force that assists local, state and federal authorities with marijuana eradication.
Johnson did not have his agency's eradication figures but estimated that CAMP has assisted with the removal of nearly 1 million plants this year. Its numbers overlap those of other agencies, including the U.S. Forest Service, which is the lead agency for multi-agency pot eradication efforts that are winding down on federal forest lands.
While the declining numbers of pot plants found on federal forest land is generally thought to be positive, there is evidence that growers are shifting their operations elsewhere, including backyards and agricultural land, officials said.
Pot growers seem to be moving toward smaller but more productive gardens on private land, said Mendocino County Sheriff's Capt. Greg VanPatten. With multiple gardens, growers are less likely to lose their entire crop during a police raid, he said.
With careful tending and plenty of light, non-forest growers also can get five to seven pounds of product per plant, VanPatten said. Forest plants tend to be comparatively spindly, he said.
VanPatten said he expects Mendocino County eradication figures to be about the same or less this year than in 2012, when 142,911 plants were seized.
But it's not necessarily because there are fewer plants being grown. Due to budget cuts, the Drug Enforcement Agency this year did not sponsor marijuana spotting training in Mendocino County, he said.
The overflight schools helped locate many of the marijuana gardens that law enforcement later could eradicate. But the county can't afford to hire planes and helicopters to find marijuana, VanPatten said.
"At $600 an hour, a helicopter gets really expensive," he said.