Authorities reported a staggering jump in the number of marijuana plants seized in California's eradication effort, claiming a more than 50 percent jump over the previous year.

The Campaign Against Marijuana Planting seized 4.4 million plants in 2009, up from 2.9 million plants in 2008, according to state Department of Justice figures released Wednesday.

The state has reported a record number of seizures each year since 2002, when more than 354,000 plants were cut down. Agents cracked the one million mark in 2005.

This year's increase was due to the discovery of larger pot gardens and the use of better eradication strategies, state Bureau of Narcotics Enforcement spokeswoman Michelle Gregory said.

Increased use of helicopters is the main factor allowing agents to find and destroy more plants, she said.

Marijuana advocates and some policy analysts have long accused the state campaign of inflating estimates of plants seized and their value on the street.

Gregory said individual agents keep a tally as they cut down plants during each raid then analysts compile totals.

Agents seized 89 weapons and made 111 arrests during the raids that started in June and ended in October. More than 75 percent of the plants seized were grown on public land, officials said.

Shasta County in central Northern California topped the list of counties with more than 557,000 plants pulled from the ground. Lake County was second with more than 506,000 followed by Mendocino County with nearly 441,000 plants.