Screams are the most valuable crop that Randy Bates reaps on his small family farm in Delaware County, and it takes a horde of cannibal rednecks, chainsaw-wielding psychos, and, of course, zombies, for the harvest.

A recent Sunday night on his 82 acres in Glen Mills saw hundreds of giddy, nervous people sitting cross-legged on trailers hitched to idling tractors as darkness crept between the cornstalks.

Around 8 p.m., a fireball lit up the sky. Then the first scream erupted and the tractors lurched forward and crawled toward the inky, awful woods. The passengers were ripe for scaring.

The calendar said Sept. 18, but Bates' 200-year-old Arasapha Farm in Glen Mills had once again transformed into Bates Motel and Haunted Hayride, making its horrific and highly profitable turn toward "agritourism" for Halloween - the holiday that's saving many small American farms.

Dozens of other farms in the region are doing the same, drawing tens of thousands of customers into their fields straight through to November.

"Halloween is 75 percent of our business here," said Bates, 58. "I'm netting $30,000 on souvenir photos alone. Unless you have thousands of acres, you're not making any money as a farmer."

Halloween has been America's fastest-growing holiday in recent decades when it comes to spending. The National Retail Federation estimates that the public will fork over $8.4 billion on Halloween this year, up from $6.9 billion last year and $5.1 billion in 2007.

Candy, obviously, has always been a big seller for the holiday, but today's children and younger millennials have access to a world of horrors older generations only dreamed of.

Come each September, costume superstores rise up in shopping centers across the country in late August. Even in Northern climes, most theme parks stay open until after Halloween now, and savvy marketing directors for historic prisons, museums, and random government buildings are inventing ghosts and ghouls if they don't have the real thing.

"This really seems to have exploded in the '90s when Halloween started to swing back from being just a kids' holiday to a holiday for adults too," said Lisa Morton, author of Trick or Treat: A History of Halloween.

"By the 2000s, it was a massive, billion-dollar business."

Bates said his farm, like many others, always offered seasonal hayrides and bonfires. But he was inspired when a neighbor started a small Halloween attraction and was overwhelmed when thousands of people showed up.

With four tractors and 25 actors, Bates opened his attraction in 1991. By 2001, he'd quit his full-time job. Now he employs 30 people at Bates Motel for 30 nights beginning in September.

"I'm now the largest employer in my township," he said.

Even farms that haven't taken the haunted-attraction route, like Johnson's Corner Farm, in Medford, Burlington County, have benefited from America's love for all things autumn.

"Our volume absolutely increases in the fall," said general manager Marcia Mondelli.

Johnson's has been in the agritourism business for decades, but it remains a daytime operation. On the first day of fall, children, parents, and grandparents bounced behind a tractor there, heading off to pick pumpkins from a 20-acre patch

Creamy Acres Farm in Mullica Hill, Gloucester County, is milking more cows than ever, said farmer Ron Ambruster, but dairy alone couldn't sustain all the families that depend on the farm.

Ambruster, 49, helped dream up Night of Terror at Creamy Acres 24 years ago. Today, it's billed as "New Jersey's Largest & Scariest Haunted Attraction" with about a half-dozen different haunts that change yearly.

"Every year I sat wondering if this was just a fad, but it just kept getting bigger and bigger," he said. "It is very competitive among the bigger guys in the tristate area, and the Philly market is one of the best haunted-attraction markets because there's so many of us."

As a boy, Ambruster spent his days tilling soil and feeding animals. Now he's the Haunted Attraction Association's "Haunter of the Year." Ambruster's father, Larry, still runs the dairy operation, but the son is on scare duty all year.

"He does the cream. I do the scream," Ambruster said.

In New Jersey, 347 of 9,000 farms engaged in agritourism, which brings in $18.4 million in added revenue, said Al Murray, spokesman for the state's Department of Agriculture.

The Haunted Attraction Association says there are 1,958 registered haunted destinations across the country; 108 of them are in Pennsylvania. The association doesn't keep track of which ones are farms.

Pennsylvania's Department of Agriculture said haunted attractions are treated like other amusements in the state, with requirements for fire inspections and adequate parking. Farmers have to learn how to move thousands of people through a dark, foggy atmosphere without injuries.

That's why Bates has actually gone into consulting, helping other farmers who want to get haunted the way he did.

"I want to help farmers get started in this and get their farms successful," he said. "We are preserving open spaces."

Richard Collison, 53, gets inspired by the "big boys" like Bates Motel and Night of Terror. For the last nine years he has transformed his R & J Farm in Galloway Township, Atlantic County, into the Cornfield of Terror.

"I'm getting ready to pull out 5,000 extension cords right now," Collison said one day last month.

The farm, he said, has been in his wife Joanne's family since the '20s, selling mostly tomatoes and potatoes before they added Christmas trees for additional income in the winter.

They started converting cornfields into a maze for the fall, then decided to throw on costumes to scare people.

Richard Collison said terror is growing more popular each year.

"We couldn't survive on a single crop," he said. "There's still some small farms around me and I don't know how they make it."