FOR ALMA Rodoni of Novato and her two daughters, letting their hair grow was a matter of helping others. They grew their hair for more than a year before having it cut and contributing it to Locks of Love.

Locks of Love, a nonprofit agency in Lake Worth, Florida, uses gifts of human hair to make wigs for children who suffer from alopecia areata. Alopecia is an auto-immune disease that causes hair loss. More than 4.7 million American men and women of all ages and ethnic backgrounds are affected, according to the National Alopecia Areata Foundation, headquartered in San Rafael.

Explaining her interest, Rodoni says, "We are always looking for interesting community service projects we can do as a family." When she heard about Locks of Love, she and her daughters - Julia and April Aaronson, ages 12 and 10 - decided to grow their hair and be donors.

Earlier this month, they went to the Trico hair salon in Petaluma, where hair designer Kathie Rothkop harvested their hair - 10 inches each from Alma and April, a full 12 inches from Julia.

"My hair now is a lot shorter than it's ever been," says Rodoni, a high tech consultant who works from her Novato home. "But I like it this way." She says her daughters were nervous about the haircuts, having gotten used to long hair, but now "everyone's happy."

The hair was bagged and sent to Locks of Love, which will forward it to wigmakers in Indonesia. The wigs will be donated to needy children (under 18) who cannot afford to buy wigs on their own.

Rothkop has promoted the notion of hair donations ever since one of her longtime clients, Sue Long of Santa Rosa, asked to donate her hair to celebrate five years of being cancer free. When Rothkop cut Long's hair, she made a videotape of the procedure, translating it later into a video about alopecia with an educational video company in Petaluma - Council for Community Television - run by her friend Joe DeVito. The film now shows daily on Petaluma's community access station, Channel 26.

Rothkop, whose forte is designing fanciful wedding hairdos and earlier made a video called "Bridal Styles Made Simple," had learned of alopecia when some of her older women clients complained about thinning hair and told her how hair loss diminished their self image.

Now she would like to do a telethon, similar to the one Jerry Lewis conducts for muscular dystrophy, where listeners would pledge money to the Alopecia Areata Foundation or Locks of Love. She would also like to recruit other hairdressers to give free haircuts to those willing to donate their hair to Locks of Love.

For hairdressers, "it's a great way to build a clientele, upgrade your image and give back to the community," she says. For hair donors, "it's a great way to give without spending money." For both, "it's a way to support needy children and to bring awareness to the broader public about the whole problem of alopecia."

Educating the public about alopecia is a primary goal of the Alopecia Areata Foundation, founded in Marin 20 years ago by Ashley Segal, then a college student who had contracted the disease. Segal was a patient of Vera Price, now of the University of California Medical Center and a nationally known expert on alopecia. The first support group was held in 1981 in San Francisco; the organization was incorporated later that year. It moved from Segal's Mill Valley living room to quarters in San Rafael and now occupies offices in Terra Linda. Its executive director is Vicki Kalabokes.

The foundation raised and spent more than $1 million last year on public awareness and research. It also helps organize support groups throughout the United States and the world, and once a year runs a national conference attended by alopecia sufferers and their families. The next will be held in Woodland Hills in June.

The foundation supplies medical information and psychlogical support for young children struggling with hair loss, teenagers struggling with dating issues and adults fearful that hair loss will impact their careers. A foundation newsletter goes to 20,000 subscribers.

Lisa Gallagher, assistant director, says the foundation works with the National Institute of Health in a project to register genetic information about alopecia sufferers, setting up a database for research. The foundation also works closely with Locks of Love, which Gallagher calls "a fabulous service" helping many foundation patients.

Locks of Love, which started small in 1997, has so far served 1,000 children, according to executive assistant Myra Reyes. The organization was once a commercial wig-making firm, until its board decided to become a nonprofit. Its president, Madonna Coffman, had a 4-year-old daughter who suffered from alopecia.

Reyes says it takes six to 10 ponytails to make one wig. "We always need hair." Locks of Love can not only use more hair, but is also looking for more children who might need its wigs: "We don't advertise, so our outreach is through word of mouth."

Rodoni says her family got great satisfaction from the hair-growing experiment. In an earlier family service project, she, her daughters and her husband, Jon Aaronson, had bought large amounts of Silly Putty, packaged it and sold it as a benefit for a family in Israel. The project was part of Julia's bat mitzvah preparation, and the family was one that had been adopted by Congregation Kol Shofar in Tiburon.

As for donating their hair, "it was a fun experience, completely painless, but a constant silent reminder that you were doing something for someone else," says Rodoni. She and her girls are considering doing it again.

"It's a great project for kids. Very visible, something you can feel very good about, helping someone who is not as fortunate as you. "We hope what we did will stimulate a lot of other people to do the same."