Hawes, who moved to Portland, Ore., from Los Angeles two years ago, died there Friday of natural causes, according to her daughter, Corey Denos of Bellingham, Wash.

Hawes, who was the daughter of legendary folk musicologist John Lomax, grew up helping her father collect and transcribe field recordings of folk musicians for the Library of Congress in the 1920s and ’30s.

In the 1940s, she had joined Guthrie, Seeger, her husband, Butch Hawes, and others in a popular, if loose-knit, folk group called the Almanac Singers that Seeger has since joked never bothered to rehearse until it got onstage. Her brother, musicologist Alan Lomax, had made some of Guthrie’s earliest recordings.

In a 2002 interview, Hawes recalled bumping into Seeger one day in New York City. She had just graduated from Bryn Mawr College in Pennsylvania and was working as a librarian.

“He told me he formed this little music group and would I like to be in it,” she said.

In the Almanac Singers, Hawes and the others collaborated on numerous songs, never crediting them to any one writer.

“As a group, they wrote a lot of songs, usually in support of union movements,” Denos said.

In the late 1940s, Hawes and Jacqueline Steiner co-wrote “M.T.A.,” a whimsical, banjo-driven tale of a harried commuter named Charlie who gets on a Boston subway, learns he doesn’t have the proper fare and is never allowed to get off. Often called “Charlie and the M.T.A.,” it became a hit for the Kingston Trio a decade later.

Hawes, meanwhile, moved to Los Angeles with her husband in the 1950s, settling into what was then a bohemian community in Topanga Canyon.

She later joined the faculty at California State University, Northridge, which honored her with a Phenomenal Woman Award in 2004. In the 1960s and ’70s, as a professor in the anthropology department, she made several documentary films exploring American music and folklore.

She also taught banjo, guitar and mandolin.

She moved to Washington in the mid-1970s, where she was director of the National Endowment of the Arts’ folk arts program until retiring in 1992. Then-President Bill Clinton awarded her the National Medal of Arts in 1993.

Besides her daughter, Hawes is survived by two other children, daughter Naomi Bishop and son Nicholas Hawes, both of Portland, Ore., and six grandchildren.

Denos said a private family service is planned next week, with public services expected later.