AS a little girl, Mamie Garvin Fields loved to visit her grandfather's farm 10 miles outside Bamberg, S.C. One of her favorite spots was a nearby marsh area called Lemon Swamp, a labyrinth of pine trees, oaks, and ferns that offered a cool haven in the steamy heat of summer.
''(The swamp) smelled like fresh herbs,'' she recalls, basking in the memory of her childhood hideaway.
For Mrs. Fields, an educator and a spirited community activist, vivid images from her past unfold as effortlessly as azaleas blooming in the Charleston sun. Her voice resonates with warmth as she describes her first experience teaching in a rural school on John's Island near Charleston, working as a seamstress in Boston to earn money for her trousseau, establishing the first day-care center in Charleston, and fighting for better housing for blacks.
Mrs. Fields, well known in South Carolina for her public achievements, which earned her the state's Senior Citizen of the Year award in 1971, reveals the richness and joy of her personal life in a remarkable oral history recently published as a book: ''Lemon Swamp and Other Places: A Carolina Memoir'' (The Free Press, New York, $16.75).
Mrs. Fields lives in a modest white frame house on the site where she was born 96 years ago. Settling into a flowered armchair in her comfortable living room, she describes how the book came about.
''I started by writing letters to my three granddaughters, writing down the various occurrences from everyday life I wanted to tell them,'' she says. One Christmas about a decade ago she presented the letters to her grandchildren, explaining, ''I want you to know what happened way back yonder.''
One of her granddaughters, Karen Fields, who teaches sociology at Brandeis University near Boston, took a special interest in the letters. Together, working from the letters and their conversations taped over a period of years, they set down the account of life in the segregationist South.
Steeped in the spirit of Charleston - a city where family and close community ties are cherished - ''Lemon Swamp'' brims with lively portraits of relatives and friends. It speaks of the struggles and victories of a vivacious, forthright woman who enjoyed a happy childhood, a loving marriage, and a teaching career despite the sting of Jim Crow laws.
Mamie Garvin grew up in a middle-class black family that put a premium on education. At age 3, she started attending an informal neighborhood school run by her cousin, carrying her own stool into the classroom. She completed her elementary education in Charleston and earned her teaching degree at Claflin University in Orangeburg, S.C.
''My family was an intellectual family,'' she says. ''We went to school when we had to hide to go to school.''
Mrs. Fields speaks proudly of one of her ancestors, a slave on a plantation outside Charleston who was sent to Oxford University with two of his master's sons as a valet. There he sat in the back of the classroom and ''learned right along with those boys,'' she says. ''When he came back to Charleston, he taught his sons. In days to come they became the first outstanding black ministers of the Methodist church in Charleston.
''In front of the College of Charleston there was a long alley,'' she continues. ''My grandfather went back in that alley and started a school for blacks. It was against the law to teach blacks to read and write, but he did it anyway. When I go to the College of Charleston today I can feel something - that's right.''
She and her husband of 49 years, Bob Fields, saw to it that their own two sons received a good education, sending them to private schools. One is now an architect in Washington, D.C.; the other is a social worker in Charlotte, S.C.
''The people who emancipated us were educated people. Blacks weren't afraid of the white man when they saw they could do what (whites) did. Education means freedom, as I see it,'' she says. ''I wanted my children to be free.''
In her own teaching career, Mrs. Fields took over dilapidated rural schools with no desks, books, or blackboards. With humor and determination she turned them into respectable places to learn.
''Never mind the hardship,'' she writes in her book. ''Most of the children who came did their best to learn, regardless. The wonderful part for the teachers (was that) we could see even the little things we did spreading through the community, and we were rewarded that way.''
In 1919, Mrs. Fields joined the Federation of Colored Women's Clubs, but it wasn't until she retired from the Charleston County School system in 1943 that she plunged into community projects and became active in other organizations. Among her accomplishments, she helped found a home in Charleston for runaway and homeless girls. She also initiated a campaign to beautify the city and drew government attention to the warehouse slums on Charleston's Cooper River to lobby for better low-income housing.
''I always worked with the mayors of Charleston. When I wanted to do a project I always went to them first - I think that's why I was so successful,'' she says.
She also had support at home.
''My husband - he was the dearest in the world,'' she says gently. ''We were friends all our lives. While I was married to him, I was always a queen. Whatever I wanted to do, he helped me do it. If I had to go to a talk, I'd come home to have dinner prepared for me. That kind of cooperation helped me succeed as a public figure.''
In 1969, Mrs. Fields mobilized city churches to establish Charleston's first public day-care facility. Today she continues to work for women's and children's rights, serves as director of the Sunday School at her church, and speaks for various educational and civic groups around the country. She is also working on a second book, a pictorial history of the South Carolina Federation of Colored Women's Clubs.
''We have borne our burdens in the heat of the day in Charleston. We had to fight for everything good we had - it wasn't handed to us,'' says Mrs. Fields, sitting erect with her eyes straight ahead. ''We did a great deal to make Charleston a better place to live.''