Quote:So far this year, police in parts of the country where cannabis is traditionally grown have chopped down plants with a street value of $12bn. The core growing area is in California, Washington and Oregon to the west, but the Appalachian states of Kentucky, Tennessee and West Virginia are also witnessing an explosion.

Quote:Ed Shemelya, who leads the marijuana eradication programme in the Appalachia region, says a new type of grower is emerging wholly different to the family cartels that have cultivated the drug for generations. "We are seeing a lot more individuals who wouldn't normally be growing marijuana. They are not your professionals."

Shemelya puts it down to the dire economy in this part of America. The region is almost entirely dependant for jobs on coal mining, which has suffered severely from the recession.

"People are growing marijuana to supplement their income or support themselves in poor economic times. This is about economic necessity," he said.

The newcomers to the business are typically restricting their practices to fields of around 80 plants - that's tiny compared to the mega cultivation seen in California where 5.3m plants were destroyed last year up from 4.9m in 2007. But at around $2,000 a plant, that still provides a good living in Appalachia.

Growers tend to locate their crops as close to their homes as possible, on the edge or just inside the forest that carpets much of the foothills. They clear foliage from the trees to allow in light, then grow the plants between the trunks to hide them from aerial detection by the drug authorities.