Around $6.5 million worth of cannabis has been found growing in state forests between Dorrigo and Nymboida.

Local police began their annual 'Cannabis Eradication Program' on March 9, using helicopters to spot the plants growing in dense, rugged bushland.

By March 12, 2,564 plants had been found and will now be destroyed.

At least one man has been charged, and police say further charges are likely.

Coffs-Clarence Crime Manager, Detective Inspector Darren Jameson, said finding and destroying cannabis is a constant battle.

"We've got some significant areas of bushland west of the Coffs Coast, and they're ideal areas to clandestinely grow cannabis," he said.

"That's a big issue for us policing wise."

Crime Manager Jameson said cannabis is a massive problem across the Mid North Coast.

"This is an insidious drug, a drug that causes significant psychological issues, long-term and short-term medical issues," he said.

"It is a gateway drug that leads on to other, stronger, chemical illicit drugs, and it is a driver of significant crime issues in the community."