Fred Moore and his lifelong buddies sure know how to throw a party.

Invitations? Don't need 'em. If you never invite anybody, then you never need to turn anybody away.

Party favors? Forget them, too. Why bother giving somebody something that they don't really want and will probably leave behind for someone else to clean up, anyway?

Booze and entertainment? Bring your own and bring your own. If you're going to a Fred Moore party, you better be prepared to bring at least one of the above elements.

Most folks choose both, however. In one hand, they carry a trusty six-pack (or a 12-pack as the case may be). In the other, they haul a guitar, a banjo, a mandolin, a stand-up bass, a harmonica or even a set of spoons.

And they come by the dozens.

It's been that way on Thursday nights for as long as Moore and his buddies can remember, or as long as they want to remember. The guys -- and even a few ladies -- have been gathering once a week for the last 30 years for what they simply call the Holmesburg Jam.

The jam, which has had various incarnations and locations throughout the years, is country to be sure. Specifically, it's bluegrass, pure and simple. And these good old city boys have gotten it down right good by now.

CHAOS IS LOTS OF FUN

"This is the best way to play," said Tim Sullivan, another of the originals and Moore's brother-in-law. "There's no organization. It's total chaos. I guess that's why we've been doing it so long."

From May to November, it's an open-air affair. These days, the guys meet at an undisclosed location surrounded by trees and out of the way of folks who might not take to the music so kindly.

The location is undisclosed because the group has had problems in the recent past with the law -- specifically, residents who have complained to police about their late-night shenanigans.

The players start meeting at about 8 p.m. The party really gets jumping at about 9. The players stand in a circle around a table or a fire, if one is available. The more experienced players occupy the inside positions, and the newer guys fall in behind.

Meanwhile, the spectators (advised to bring their own lawn chairs if they expect to find a seat) create an even larger circle around the jam.

The party goes strong until at least 11 p.m. Usually, it goes on later than that. It's been the same way since Holy Thursday 1971, when the original group first jammed in the basement of George Steck's parents' house at 4428 Marple St.

A few years later, Sullivan's brother, Bill, moved into an apartment building at 8027-29 Frankford Ave. Moore, now known as the "Godfather" of the Holmesburg Jam, was also living there at the time. The property had a large back yard that was home to the weekly parties for more than a decade.

HEY, DO I KNOW YOU?

The events were more than jams, however. They were family reunions of sorts. The Sullivans and Steck are cousins. Meanwhile, Moore is married to the Sullivans' sister, Fran. And even those in the group who are not related by blood developed a family-like affinity for one another.

"We had the back yard up there on Frankford Avenue for seventeen years," said Will Cahill, another original member of the group. "The Northeast Times (then located at 8033 Frankford Ave.) had their skids out there, which we used to set the fire. It was surrounded by trees, so we didn't bother anybody.

"That back yard was like a private paradise. We started at nine (at night) back then and would go to three in the morning."

"We made an endless supply of skids vanish," Moore added. "It would pour rain, and we wouldn't get wet standing next to the fire."

The jams continued, gaining more and more of a following in that back yard until the late 1980s, when the last of the group moved out of the apartment building. The owner didn't want them hanging out in the yard any more, so they moved to a parking lot next door. That site lasted for another dozen years.

"In ninety-eight, the cops finally said 'You're out of here,'" Moore recalled.

Next, this traveling band set up shop in a park at Delaware and Linden avenues in Torresdale. With the river in the background, trees overhead and a large group of enthusiastic park users eagerly listening, the jams became full-blown free concerts.

DOWN BY THE RIVER

"When we went down to the river, it was nice," said Moore.

"It was the first time we ever had a real audience," Moore continued.

"It was new to us. The seniors would set up lawn chairs. Word of mouth got out."

Not everyone was impressed. According to members of the group, local police began to usher them out of the park at 10 p.m. after neighbors complained that they were violating park hours.

The decision to move for good was a no-brainer. Although they enjoyed bringing bluegrass to the people, there was no way they would pack things up at 10 every week.

So now, they have a new place. It's working out for the time being, they say.

"Everybody brings their own -- whatever they want to drink, whatever they want to play," Tim Sullivan said.

The group draws on a repertoire of songs -- some traditional bluegrass, some adapted from other genres and some penned by Moore, known as a prolific writer.

"Fred's a writer, and we do a lot of his songs," Cahill said. "But he doesn't want to go out with a band and tour. We do it just for the music and the camaraderie."

Moore even wrote a song about a deceased member of the group, Fran Hoffman. They play the song to both honor and remember their friend, who, they say, was the heart of the group during his time with it.

"Fran Hoffman was an inspiration," Tim Sullivan said.

"Fran was the consummate showman," Steck said.

"We'd listen to him sing and play and tell stories," Tim Sullivan continued. "He was the guy who everybody started gathering around."

Even without Hoffman, the players are committed to keeping the Holmesburg Jam going strong. They always welcome younger players to join in the fun and maybe learn a thing or two.

People come and go all the time, but new players are always showing up. The jam has given itself some publicity with a Web site that contains a history of the group, features about current and former members and tons of photos from the group's excursions to various folk and bluegrass festivals, as well as appearances by some of its members on stage.

The site lists dozens of other jams and sites from throughout the region for those looking to try their picking elsewhere. But, as far as they know, theirs is the only thing of its kind in the city.

"You just don't see this in Philadelphia," Cahill said. "It's so down home."

Visit the Web site www.icdc.com/~fmoore/ for more information on the Holmesburg Jam.