When Wylie Gustafson takes the stage at the 2003 National Folk Festival, you’ll probably notice a few things about his appearance. He’s a yodeling cowboy. Hence, he wears a cowboy hat, Wrangler jeans and a Western-style jacket that’s more Hollywood than home-on-the-range. What you may not notice are his boots.

Sure, all cowboy singers wear cowboy boots. But Gustafson’s have a greenish tinge about them, right where the sole meets the upper. It’s there on purpose.

“It’s actually from walking out in cow pies out in the pasture,” Gustafson said by phone from his ranch in Dusty, Wash. “They’ve been baptized, so to speak, in cow manure.”

The clothes make the man, so goes the saying, and in the case of the National Folk Festival, the clothes often make the band. Much of the appeal of traditional folk music lies in its authenticity, and dress is a big part of the act, whether it’s a pasture-ized boot or a robe hand-dyed in Africa.

Mamadou Diabate, a jeli, or musician-storyteller, will take the stage in Bangor wearing a deep green boubou (pronounced boo-boo). The capelike garment is made of cotton that is woven and brushed to a glasslike sheen. Then, women in Diabate’s native Mali dye the fabric in a rainbow of symbolic colors.

“Green means the presence of nature,” Diabate said by phone from his home in New York. “For me, I love the green. You see green, you see the forest. It begs you to see the natural.”

Green or otherwise, the boubou also begs the viewer to see the tradition behind the music. It is a respectful garment, worn by dignitaries (or those who play for them) in West Africa. Diabate is descended from a long line of jeli, or griot, musician-storytellers who serve as oral historians within the culture, and his clothing is a nod to his rich heritage.

“For us it’s normal to be wearing these clothes,” Diabate said. “If we’re not wearing that, we feel like we’re not presenting you with the traditional music.”

Many of the members of the Sounds of Korea, a music and dance troupe, were born and raised in the United States, so the link between their performance and their homeland is a bit less direct. Their customs have been passed down from older generations, and their costume, called Hanbok, is something they wear only onstage.

Because their tradition has its roots in rural, agrarian Korea, the men in the group wear baggy pants and a wrap-style top, all in white. Farmers couldn’t afford to buy dyed clothing, and they wore loose garments in the fields.

“Traditional music and traditional performing arts, dance and music all basically come from everyday life,” Gloria Pak, the group’s spokeswoman, said by phone from Los Angeles. “A lot of folk music comes from common people; it comes from religious rituals, dances done in celebrations in villages for special occasions, or to celebrate the harvest.”

Over time, these rituals made their way onto the stage, and traveling musicians, similar to minstrels in Western cultures, took to the countryside. As their music and dance became more professional, their costumes evolved – they added vibrant, pageant-style banners to the traditional white farmer’s garb, as well as red or black vests.

The women in the group wear short, wrapped tops over floor-length dresses when they sing. Though the sleeves are long and flowing, the bodice is bound tightly to make the breasts appear smaller, thus more attractive in the Korean tradition.

“Korea is a very gendered society, so you would never, back then, see a woman wearing pants,” Pak explained.

When the women dance, the whole outfit is bound to their bodies for easier movement. It’s a custom that dates to Korea’s courtesans, who elevated the folk traditions to an art form.

“They’re considered to be the origin of all artistic things in Korean traditional music and dance,” Pak said. “They were really talented and they really improved it.”

In the case of Sounds of Korea, the outfits are an integral part of the performance. However, not all of the performers incorporate elaborate costumes into their act. The young members of La Bande Feufollet, who play Cajun music, wear what one of their mothers describes as “teenager clothes.”

“[They’re] very down-to-earth,” Lisa Stafford said by e-mail. “Not dressy or showy, just themselves – that’s how they like it.”

And that’s what clothing is all about: a means of expression. Dress can serve as an homage to the past, a cloak of legitimacy, or a nod to tradition. It can add to the performance, or it can simply fade into the background and let the music get all the attention. But don’t be fooled by appearances – even jeans and a pair of boots have significance.

Just ask Wylie Gustafson, a real-life cowboy who works on an honest-to-goodness ranch. He doesn’t wear Levi’s. He wouldn’t be caught onstage in anything from the Gap. He wears Wrangler MWZ-13 jeans, because it’s the right thing to do.

“Any cowboy will understand the reference,” he said. “That is the style of Wrangler jeans that all cowboys wear. You’ll look funny if you go to compete in a rodeo and you’re not wearing these jeans.”

But the rest of the outfit is another story. It doesn’t have to be completely authentic to be the real deal.

“There’s a little bit of a difference there between what a real cowboy wears and what a Hollywood cowboy wears,” Gustafson said. “If we wore what a real cowboy wears in terms of jackets, we’d look pretty ragged. It may not ring true in the folk sense, but it rings true with the tradition of the genre for some reason.”