The Newton Music Festival, set in a leafy park in Cheshire, isn't exactly Glastonbury. Attractions include a fairground and a heavy metal band fronted by a bald man with a beer belly. This is, however, the ideal place to encounter Hayseed Dixie. Unfortunately, two hours before the band are due onstage, Hayseed's giant frontman, Barley Scotch, is fretting about the disappearance of both his band and their beer, although not necessarily in that order.
"They've pranged the car," he drawls, clutching a mobile phone to his psychedelic T-shirt. Much later, the band pull up in a taxi clutching mandolins, beer crates and at least one T-shirt reading "Big balls".
"We had a minor scrape on the highway to hell," admits banjo man Reverend Don Wayne Reno. It transpires that they crashed while doing 5mph in the hotel car park, but managed to write off two vehicles.
Few bands embody the spirit of Spinal Tap quite as well as Hayseed Dixie. Their latest album, A Hot Piece of Grass, features the band pictured alongside a horse's behind. Their "rockgrass" music consists mostly of deranged, hillbilly-bluegrass renditions of rock classics. These "Dixiefied" songs include Led Zeppelin's Whole Lotta Love, during which Scotch carefully updates the "I'm gonna give you every inch of my love" line; "In the UK," he says, "that's every centimetre."
Some critics believe Hayseed Dixie's berserk cover versions are better than the originals. The acclaim they have received led them to a recent appearance before a startled mainstream audience on BBC TV from Glastonbury, where they took the stage "before those Coldplay guys".
Coldplay songs are unlikely to make it into the Hayseed repertoire, which stretches from Queen's Fat Bottomed Girls to Franz Ferdinand's This Fire and consists of songs chronicling "drinking, cheating, killing and hell". The first ingredient seems especially important. Dixie deliver "songs that are fun to play while drinking beer and are hopefully fun to listen to while drinking beer".
"I'm not trying to advocate alcohol," says Scotch soberly. "But I love beer!" However, they never get so drunk they can't play. Well, except for one night in Dallas. "I'm no Shane MacGowan," says Scotch.
In fact, he isn't really Barley Scotch. His real name is John Wheeler; he runs a recording studio in Nashville. He has long subscribed to the Guardian "for that European, leftwing perspective" and he has a PhD.
In the official Hayseed Dixie story, they were a bunch of hillbilly pickers in the outpost of Deer Lick Holler who discovered AC/DC after finding a crashed car containing their albums. Which is only a moderate embellishment of the truth.
"There are a number of places in the Appalachian mountains that people call Deer Lick Holler," says Scotch/Wheeler, in a drawl reminiscent of haystacks and moonshine. "Because of the rocks, the water has a high salt content, so when the saltwater bubbles up the deer come to lick it. So people holler, 'Let's go hunting at that deer lick!' "
Many moons ago, his parents left the mountains and drove to Nashville to get work. He claims his father had 14 brothers and sisters, his mother nine. They're still there, some making moonshine, although, Scotch says, "It's more of a connoisseur thing now."
As a child, he was fascinated by musical instruments. At the age of 10 his father took him to see Hank Williams Jr, who had an album out called Whiskey Bent and Hell Bound. The record he bought next was AC/DC's Highway to Hell. To him, there didn't seem much difference.
"They were singing about the same stuff, from the perspective of a working class guy who's reserving his right to fight the man and raise some hell!" A few years later, he hooked up with the Renos - "Rev" Don Wayne and his brother Deacon Dale, the sons of famous Duelling Banjos picker Don Reno - when they recorded at his studio and they bonded picking tracks by AC/DC.
Inspired, they recorded their first album, A Hillbilly Tribute to AC/DC, added live bassist Jason D Smith and Dixie took off from there, although it wasn't always easy. Some biker/metal fans accused them of "desecrating metal", but AC/DC gave Dixie their stamp of approval and the rebels shut up. Country audiences have generally been less receptive. "We opened for one big country act before 50,000 people, all of them 50-year-old line-dancers," grins Scotch. "They just didn't get it. It was just, you know, clap ... clap ... but they didn't throw things at us."
In fact, as some critics have noted, Hayseed are supreme musicians who honour the traditions of bluegrass and country, especially as Scotch's own compositions have started to feature more prominently on their albums. One song, Uncle Virgil, a typical country tale, tells the true story about an uncle of the Renos, who had his own difficulties with transport. "He went to catch the train and the darned thing hit him," sighs Scotch. "Dragged him 100 yards."
Their most famous self-penned composition deals in obsession and revenge, the sort of thing you'd get from George Jones or Merle Haggard - admittedly not with a title like I'm Keeping Your Poop ("in a jar").
"You know everyone's got that one lost love," explains Scotch. "I wrote that song about her because about a week before we broke up we were talking about Howard Hughes. He used to keep his fingernails and his pee and his poop! It's a diagnosable neurosis. But when she dumped me I realised that I was as obsessive, I was carrying all this stuff about her in ma fucking head!"
The poop is currently available among the merchandise at Hayseed Dixie's website. Scotch opens another beer. Occasionally, the persona slips and he reverts to John Wheeler. He is an intelligent, politically aware man who can expound on US foreign policy and give complex 15-minute discourses on why the world's ills are all the fault of Plato.
His beliefs do spill into Dixie - it's no coincidence that Black Sabbath's War Pigs now features in their live set - but he doesn't want politics to sour the band's hollerin' and drinkin' manifesto. "It was difficult for us when the war started because in Europe we kept getting asked about Bush," he says, "but we don't represent anybody's government. It's about bringing people together. I've played biker rallies where people who hate each other leave their guns at the door and maybe some will end up talking to each other and realise they have things in common." Which is why they'll keep on playing to anybody who will have them (and a few who won't).
The day before we meet, they played something called the Trowbridge Village Pump Festival. "A pump's a fart, right? We played a festival of farting!"
Next up is the Cambridge Folk Festival, on Thursday. "That's a serious festival, right?" says Scotch, eyes glinting. "We' ll try not to crash the car."
· A Hot Piece of Grass is out now on Cooking Vinyl, along with a Hayseed "best of" album, Let There Be Rockgrass.
