This Sept. 17, 2013 photo shows American musician Linda Ronstadt poses in New York to promote the release of her memoir “Simple Dreams.” (Amy Sussman/Invision/AP)

A 67-year-old woman in a black hoodie stepped gingerly down from a golf cart at last weekend’s National Book Festival on the Mall. Battling Parkinson’s disease, she steadied herself with two walking sticks, and headed, one careful step at a time, toward the stage.

The applause started as a small ripple as the first few people in the audience spotted her. Then it grew into a full-throated ovation by more than 500 fans as she stepped up onto the stage, smiled shyly, and flashed the luminous chestnut eyes that made America fall in love with Linda Ronstadt.

“I guess I have friends here,” she said, to the roaring approval of a crowd that skewed a little gray, many still with a bit of a crush on the woman who sang such songs as “Blue Bayou” and “You’re No Good.”

As part of the festival program, I interviewed Ronstadt onstage about her new memoir, “Simple Dreams,” which focuses on her upbringing in a musical family in Tucson and the evolution of her career. One of America’s most popular recording artists of the 1970s and 1980s, she has been called the most versatile singer of her generation, a talent who could master rock and country and mariachi. Because of Parkinson’s, she’s no longer able to sing.

Singer Linda Ronstadt performs at the Providence Civic Center in Providence, R.I., on Aug. 8, 1978. (ASSOCIATED PRESS)

As we spoke before a crowd of fans, many of whom had lined up hours early, Ronstadt’s backstage shyness faded. Onstage, she seemed stronger, a force — and very funny.

“We weren’t all having orgies and smoking a big spliff,” she said, when I asked her to talk about the “sex-drugs-and-rock-and-roll” lifestyle we all associate with rock stardom. Those stories are exaggerated, she said, and her nightlife was often cuddling up with her stuffed panda reading “Anna Karenina.” She admits that she did drugs, like so many others in her orbit then. But she said they weren’t really her thing: “My addiction was to reading.”

The jet-set days, a different city every night, were not always glamorous. Her luggage often didn’t arrive in time for the next gig, so she kept a favorite striped dress rolled up in her purse. She even wore it on “The Johnny Cash Show” and tossed it only because it was made of a “strange synthetic material that kept shrinking and shrinking” after so many washings in hotel sinks.

Ronstadt’s face — captured on millions of album covers — is still soft and open, but she is heavier now and it has rounded out a bit more. Her eyes still have breath-catching depth and luster, and her wit is razor sharp.

While others of her era have kept on touring, she left the road behind long ago. It wasn’t because of her Parkinson’s, which was diagnosed only recently. She said her dramatic life change occured when she adopted two children, who are now 19 and 22.

Millions of men in were in love with Ronstadt, but she never said “I do” to any of them. “I’ve had lots of nice boyfriends,” she said, describing herself as a devotee of “serial monogamy.” And, then to the delight of the crowd, she added, “with emphasis on the ‘serial.’ ” She was faithful to one boyfriend at a time, but never to one for all time.

“It just wasn’t a requirement for me. I’m not gifted that way. I have great respect for people who do make those kinds of compromises and really build each other up. The only reason to be with somebody is that they make you a better person and you make them a better person.”

Ronstadt famously dated California Gov. Jerry Brown in the late 1970s; they appeared together on the cover of Newsweek. In her memoir she said he was unlike many of the men she met through her music: “He was smart and funny, not interested in drinking or drugs, and lived his life carefully, with a great deal of discipline.”

Ronstadt said she is not political, per se, but she is a Democrat who gets fired up about the immigration debate, which hits close to home. Her father’s family has Mexican roots, and she told me she has many relatives in northern Mexico and Mexico City.

In our interview, she talked about great American songwriters and composers such as George Gershwin, the son of Jewish immigrants from Russia. She said that the golden era of 20th-century American music was nurtured by immigration.

“It was completely created by the fact that we were a nation that was welcoming to immigrants,” Ronstadt said, the edge in her voice sharpening. “We allowed them to come in and find their place. We allowed them to prosper, which is what people from Mexico and Guatemala and El Salvador and Liberia and Libya and all these people would be doing now if we let them.

“We need to help them find their place,” she said. “I don’t know why this country doesn’t learn.”

After the interview, as we waited for a driver to pick us up, Ronstadt stood in her cotton hoodie and comfy leggings on the sidewalk at the edge of the Mall. A young woman, maybe 20, walked by and dropped her lipstick. Ronstadt called to her and when the woman turned around, Ronstadt used her walking stick to point out what had fallen out of her purse. The girl picked it up, not giving Ronstadt the time of day, and moved on, no clue that she had just crossed paths with a superstar who has sold more than 100 million records.

During the ride back to her hotel, we pass the White House, which she said she has visited several times, including a meeting with President Obama — a man she praised for his “great dignity.”

She doesn’t dwell on her Parkinson’s. In fact, sometimes it comes up as almost an afterthought. Onstage, she had talked about how music stirs emotion.

“I always say if music can’t make you cry, you’re a hopeless case,” she said. “I don’t cry very much myself, but it’s my job to make you cry.”

Then she remembered, and corrected herself quickly: “It used to be my job.”

It’s not just the singing that she misses. She has always been a big knitter and loved making sweaters. Her ability to hold the knitting needles is gone, too. “It is a blow,” she said quietly in the car.

I asked her how she copes with the loss of her great gift, her voice.

She said these days she spends a lot of time at a cultural center near her home in San Francisco that caters to Mexican immigrant youth. She said she’s worked there for years but now has more time to help immigrant kids learn music and art, and is trying to keep them on the right track.

“I have to keep reminding myself that I had an unusually long turn at the trough,” she said. “I had a lot of chances to do things that other people don’t ever get and I have to be content with that. I have to look around for some other way to make myself useful.”

CONTEMPORARY SINGERS SHE ADMIRES: Duffy, Janelle Monae, Adele and the late Amy Winehouse.

ADVICE TO OTHER MUSICIANS: “I am a believer in discipline; it takes a lot to do well. You need discipline for those little excursions into the chaotic that make life interesting.”

FAVORITE FOOD: Tea and toast

WORDS TO LIVE BY: “Be regular and orderly in your life, so that you may be violent and original in your work.” (Flaubert)