SANGER, Calif. (AP) - This summer, California narcotics officers have pulled millions fewer pot plants from the state's remote forests than in past years. The reason, investigators say, is that drug traffickers have come down out of the mountains to plant pot in plain sight in backyards and on prime farmland, where California's medical marijuana law makes them tougher to bust.
Historically, growers of large-scale illicit pot gardens relied on the cover and isolation of California's wildernesses to protect their plants. Last year, the state's annual campaign to root out such grows netted more than 4.3 million plants worth billions of dollars. This year, however, the number of plants seized dropped by almost half.
State anti-drug agents say traffickers have migrated to California's Central Valley, one of the country's most fertile agricultural zones. From here, they say pot grown on tree-sized plants makes its way not just to California's storefront marijuana dispensaries but also to street dealers across the country.
In Fresno County alone, investigators typically expect to find 60 to 80 large grows in the mountains, said Lt. Richard Ko, head of marijuana eradication for the county sheriff's office, in response to inquiries from The Associated Press. In 2011, they found nine, he said. Meanwhile, the number of large pot farms on the Valley floor rose to 121 countywide, up from 37 in 2010.
Instead of huge, isolated gardens, traffickers have turned to networks of smaller growing operations, investigators say.
Their smaller size keeps them off the radar of federal agents seeking bigger hauls, and local prosecutors are wary of pursuing cases against growers claiming the pot is for medical use, said longtime narcotics agent Brent Wood.
"We can't touch `em, and it's everywhere," said Wood, who commands the multi-agency Central Valley Marijuana Investigation Team.
Investigators say growers often lease plots from landowners or farmers. In some cases, the growers are small farmers themselves who grow pot to supplement their incomes or simply raise other crops as a cover from onlookers' eyes.
During a helicopter flight over Fresno County this past week, pot plantations were easy to spot. Ko pointed out farms where marijuana plants covered dozens of acres. Most of the massive grows were fenced and surrounded by vegetables on trellises. Some were concealed within abandoned orchards. On several grows, workers harvested plants and dried marijuana on tarps.
Over the city of Fresno, Ko pointed to dozens of pot plots in the backyards of homes.
On the ground, Ko drove down a dirt road to a farm on the outskirts of Sanger, near Fresno. Above tall vines of yellowing melons, marijuana plants the size of fruit trees were just barely visible. The plot of about 60 plants was surrounded by a fence decked with lights and motion sensors.
Three growers approached Ko and presented makeshift medical marijuana cards.
One grower, Mike Kipraseut, led Ko past a pit bull and a lookout platform in a tree. Several pot plants were on the ground, chopped at the stems. The family, who said they were refugees from Laos, decided to get rid of the plants, Kipraseut said, because they had seen the helicopter circling earlier that week. In any case, he said the plants would not mature in time to harvest them before the rains.
Kipraseut said this was the first year he had grown pot and that he sells vegetables for a living. He said he smoked it for headaches following brain surgery. His uncle, who didn't give his name, said he suffered from back pain.
"I'm not going to do it next year," said Kipraseut, whose family leases 20 acres of farmland at $500 per acre. "It's too much of a risk."
Ko asked if the family wanted help in getting rid of the plants, and they agreed. Later that day, federal agents dragged the plants to a trailer that would haul them away. The family would not be arrested because they had cooperated with authorities, Ko said, adding that similar marijuana plots were growing on four nearby farms.
Growers often post multiple pot recommendations or ID cards near their gardens, investigators say. Under California's landmark 1996 ballot measure, patients with a doctor's recommendation or their caregivers can grow pot for medical use. The state Supreme Court found last year that the measure trumped a later state law limiting how much pot a patient can grow. Efforts by counties to restrict the number of plants per patient were left in limbo.
"Some fields have hundreds of recommendations from doctors," Ko said. "In order to get them, we have to catch them selling out of state or for profit."
Investigators believe much of what's grown in farms and backyards as medical marijuana gets shipped as far as Texas, Illinois and Boston. While a glut of high-grade marijuana has brought wholesale prices in California as low as $900 per pound, agents say the same pot on East Coast streets can bring up to $3,000 per pound.
Hundreds of pot plants can be grown per acre, each potentially yielding a pound or more of pot.
"I don't know of any crop that brings that kind of money per acre," said Ryan Jacobson, director of the Fresno County Farm Bureau.
Earlier this month, federal prosecutors announced a crackdown on hundreds of California pot dispensaries who were warned to stop selling pot or face prosecutions and asset seizures.
But several federal cases highlight the scale some farmland pot farms have reached.
Agents raided a 54-acre farm near Sanger in November 2010 and pulled up nearly 4,400 plants and seized more than 1,100 pounds of processed pot.
In July, agents returned and found about 25,000 plants growing in a sophisticated operation staffed by 50 workers, protected by barbed wire and a lookout tower. Those plants were uprooted, but officials said the site was replanted again -- this week agents pulled out more than 200 plants.
As with several other landowners accused of leasing to pot growers, federal prosecutors are seeking to seize the land.
Growers appear to find the profits worth the risk. The region has abundant sunlight and irrigation, and fertilizer is as close as the nearest hardware store. Investigators claim the marijuana plants grown on farmland yield five pounds of pot compared to one pound per plant raised in the forest, where growers sacrifice sunlight to keep plants hidden from law enforcement flyovers.
Said Wood: "These backyard grows have been producing these monster marijuana plants like I've never seen in my life."