After living in a climate of real-life horrors and scares for nearly two months, many Americans are muting Halloween's fear factor and abandoning some of its traditions this year.

"You can't say this has been a positive environment for Halloween," said Larry Kirchner, president of Halloween Productions in St. Louis, the country's largest supplier of haunted houses.

The already declining haunted house business is sagging even more in the post-Sept. 11 world. Trick-or-treaters will be scarcer. Costumes promise to be less gory. And parent groups say going door-to-door for candy is out for many children.

"I've heard from a number of parents who have decided the thing they want to do is have a home party instead of going trick-or-treating," said Shirley Igo, president of the national Parent Teacher Association.

The PTA is encouraging parents to accompany kids if they do go out — even the older, pre-teens — and to instruct them not to eat any candy until it's been checked at home.

One mother of three, M.C. Keegan-Ayer of Frederick, Md., said families in her neighborhood have had a trick-or-treat plan in place for years and will use it again Wednesday. One parent will stay home to hand out candy while the other goes with the children — to familiar houses only.

And, she added there are some differences in how her family and the community are treating the holiday this year. "Halloween decorations are not quite as macabre as they have been," she said. "My son was going to lay out in the front yard and pretend to be a World War I dead soldier and I told him that was not a good idea."

Parent Colleen Bullock of Clackamas, Ore., also plans to have a hand in what her 15-year-old son does. He and his friends usually set up fake tombstones in the grass, dig a hole to lie in and pop up when trick-or-treaters come by.

"I'm not sure they would do that this year," she said.

Igo said the PTA is encouraging parents to closely monitor their kids' costumes and make sure they're "culturally appropriate."

"Any kind of costume that's reminiscent of the tragedy or terrorism could cause problems," she said.

Haunted houses have experienced the same toning-down trend. Some themes have been scrapped because they too closely resembled the terrorist attacks — like the $2 million Fright House in Washington, D.C., featuring an "Escape from the Pentagon" scene that was created before Sept. 11.

The House of Fire attraction, with a crematorium in flames that had demonic firefighters leading people to Hell, was also cut at Castle Park in Riverside, Calif.

"We could not continue, just out of respect for the people who lost their lives — particularly the firemen and policemen of New York City," said Castle Park general manager Ed Pearson.

And a deranged Green Beret character covered with blood and wielding an AK-47 has disappeared from Skull Kingdom in Orlando, Fla., as have zombie businessmen in bloody suits, according to general manager Doug Wolfe.

But not all fright can be eliminated, he said. "It is a fine line, but the way we do our job is to scare people," Wolfe said. "If someone's really paranoid about what's going on, I would hope they would not come to a haunted house."

Halloween Productions' Kirchner thinks people still want to be frightened this year — especially in a controlled fantasy world where the scares aren't real.

"A haunted house is no different from riding a roller coaster," he said. "It's fun to walk in there and not know where you're going but know you're safe."

Still, the decrease in haunted-house goers suggests that a significant number of Americans aren't in the mood.

Kirchner estimated that the business has seen a 20 percent drop this year. He also speculated that many stores relying on the holiday to boost retail sales will go out of business. Halloween is the second-largest retail holiday, after Christmas.

But regardless of the changes in the holiday, most agree that Americans won't let the terrorists stop them from enjoying the thrills of Halloween.

"It's such a traditional American celebration," the PTA's Igo said. "It will go on."

The Associated Press contributed to this report.