Deep in the hills of Appalachia, the U.S. government is waging war against the richest cash crop in Kentucky - marijuana.

Its planting season has just ended. Most of the crop has been sold in advance in deals sealed the old-fashioned way, with a handshake. The planters' booby traps are in place.And between now and harvest time in autumn, a small army of government agents will do all it can to destroy plants that yield at least $1,500 apiece and form part of a nationwide underground economy worth billions.

Marijuana is grown in all 50 American states, but five - including Kentucky - account for more than half of domestic production, according to government figures.

In Kentucky, poverty, a tradition of risk-taking, and a pronounced streak of stubbornness among the mountain people combine to make the anti-drug effort particularly difficult, drug experts say.

"The same areas that produced moonshine whiskey are the areas that now produce marijuana," said Bill Dixon, the U.S. Forest Service agent in charge of the Daniel Boone National Forest where much of Kentucky's marijuana is grown.

"This is because of the remoteness of the area, the level of poverty, the lack of jobs . . . Entire communities revolve around the illegal product."

The heirs of Kentucky's prohibition-era moonshiners employ tactics reminiscent of the Vietnam War to protect their plants: trip wires linked to dynamite charges, sharpened sticks at the bottom of concealed pits on tracks leading to marijuana fields, fish hooks set at eye level.

The government deploys spotter planes, helicopters and heavily-armed national guardsmen who last year slashed and burned 616,000 plants. Enough escaped detection to keep Kentucky in the Big Five marijuana states.

Barring a miracle, drug experts say, Kentucky will stay on top of the list: marijuana is the only business that flourishes in eastern Kentucky and Appalachia, a range of hills that has become a byword for rural poverty in the United States.

The arguments some of the locals use to defend the illicit crop echo drug-cultivating peasants of Latin America: give us an alternative source of income and we take it.

Since the price of coal, one of the pillars of the Kentucky economy, fell in the mid-1980s, more than 14,000 mining jobs have been lost. Only two of the 20 coal mines that operated a decade ago have survived the slump.

Profits from tobacco, the other economic pillar, cannot compete with marijuana which allows even small-time growers to clear more than $100,000 a year.

So, hostility to government eradication efforts runs deep.

"There are some counties where they will tell us there's no other way to make a living," said Dixon. "When we pull up there, they won't sell us gasoline, they won't even sell us a cold drink, they close the shops."