MEDICINE MAN: David Verstoppen with grandson Michael Hergenroeder. Both survived an Oct. 31 home invasion.

When two men with bandana masks burst into David Verstoppen’s living room in Eastern Oregon on Halloween night, he assumed they were trick-or-treaters and reached for the candy bowl.

But when one of the intruders cocked a semi-automatic pistol and demanded he hand over his award-winning marijuana crop, Verstoppen, 53, wound up in a fight for his life.

While his wife and sister-in-law fled out the front door with his 2-year-old grandson, Verstoppen grappled with the gunman while the second invader beat Verstoppen over the head with a 7-iron golf club until it broke in half.

“I think that’s when he realized I wasn’t going down,” says Verstoppen, a 5-foot-10-inch former timber feller who weighs 220 pounds. “He just looked like a little punk gangbanger. It pissed me off.”

Partially blinded by his own blood, Verstoppen nonetheless managed to drive the men out of his house. Both suspects and a third accomplice have since been arrested.

Armed robberies are so rare in Verstoppen’s Eastern Oregon hometown of Long Creek, population 228, that he can’t recall another during his 17 years living in the isolated hamlet.

But it’s also no secret that Verstoppen, who suffers chronic pain from work injuries, cultivates some of the state’s best ganja. For three years running he’s won top honors at the Oregon Medical Cannabis Awards for his Dynamite and Medicine Woman strains, which he grows legally for himself and three other patients under the Oregon Medical Marijuana Program.

Ten years after Oregon voters legalized medical weed, the state’s growing number of legal growers have now become targets for violent crime. With pot selling for about $4,000 a pound on the black market, cops and pot advocates say growers are increasingly victimized by armed thugs looking to steal their crops.

At least 25 growers around the state have been victims of violent heists in the past five years, says Paul Stanford, head of THC Foundation, a chain of nonprofit medical marijuana clinics. They include big-city growers, suburbanites and rural residents like Verstoppen.

Stanford’s own garden in outer East Portland has twice been hit by burglars who absconded with plants in the night. Now he pays $400 a week for guards.

Washington County has seen two violent attacks on rural marijuana grows in the past 13 months. Most recently, three men and a woman were watching movies at a home in Banks on Aug. 13 when five to seven masked invaders burst in, two of them with guns.

They tied up the victims, demanded money and marijuana being grown legally for patients, and brutally beat the three men when they didn’t receive all they believed was in the house. They got away with an undisclosed amount of cash and freshly harvested marijuana, and have not been caught.

“There is a growing violence around these grows, and the public in general isn’t really aware of the number of grows that are out there, or even if there’s a grow in their neighborhood,” says Sgt. David Thompson, spokesman for the Washington County Sheriff’s Office.

It’s not hard to understand the violence if you consider the spoils. Under state law, a grower may cultivate for up to four people, plus herself if she’s also a patient. For each client, a grower may have up to six flowering plants. With a skilled grower, an outdoor plant yields about two pounds of dried marijuana. With the maximum 30 plants, that’s $120,000 worth of green.

Law-enforcement officials complain that many growers use their legal designation as a fig leaf to raise far more than they’re allowed by law, selling the extra for profit. Some cops have seized on the latest attacks to call for increased oversight of the entire medical-marijuana program, with Washington County leading the charge.

That’s renewed a long-running battle with advocates, who say a crackdown would only further limit patients’ access to medicine and violate their privacy.

“Would you want the police coming into your house and going through your medicine cabinet?” asks Jerry Wade, spokesman for the nonprofit Stormy Ray Foundation. “What we’re proposing is more education for the people that are growing these gardens.”

Stanford says the solution is to take the trade out of the criminal realm by taxing and regulating marijuana. He’s gathering signatures for such a measure in hopes of placing it on the 2010 state ballot.

Meanwhile, the attack hasn’t slowed Verstoppen. While still recovering last week with 10 stitches in his scalp, he sent his latest strains to compete in this year’s Oregon Medical Cannabis Awards.

He says his attackers were not tipped off because of his past prizes, which were publicized online with a map to Long Creek. He says it was a ne’er-do-well acquaintance and his cronies. Now Verstoppen hopes to take top honors again when the awards are announced Dec. 13.

“I feel real confident,” he says. “The strain that I’m entering is very medical.”

Last week, Michigan became the 13th state to legalize medical marijuana.