Joyce Carol Thomas in 2004. (Mike Kepka/The San Francisco Chronicle)

Joyce Carol Thomas, a National Book Award-winning author who drew on her own experiences in writing books for children and young adults that accented her rural African American heritage, died Aug. 13 at a hospital in Palo Alto, Calif. She was 78.

The cause was complications from liver disease, which she developed as a result of a tainted blood transfusion years ago, said her sister, Flora Krasnovsky.

After beginning her writing career as a poet and playwright, Ms. Thomas published her first novel for young readers, “Marked by Fire,” in 1982. Set in her home town of Ponca City, Okla., the book introduces a memorable and resilient character, Abyssinia Jackson, who appears in several subsequent books and becomes something of a mythic figure.

Ms. Thomas grew up working in the Oklahoma cotton fields, and as a child was burned on her leg and bore the scar for the rest of her life, her sister said. Abyssinia shares a similar background.

Born in a cotton field in the midst of a brush fire, she was scarred on her face and, according to a local healing woman, “marked for unbearable pain and unspeakable joy.”

Joyce Carol Thomas in 2004. (Mike Kepka/The San Francisco Chronicle)

Abyssinia possesses a remarkable singing voice until she is rendered mute by a sexual assault by a church elder — a scene that mirrored a trauma experienced by one of Ms. Thomas’s childhood friends. The novel then chronicles Abyssinia’s struggle to regain her voice and her dignity.

“Miss Thomas writes with admirable simplicity and finds a marvelous fairy tale quality in everyday happenings,” playwright Alice Childress wrote in the New York Times in 1982. “Her people move through troubled times but never fail to celebrate sweeter days with church suppers and the joyous sound of gospel singers.”

“Marked by Fire” was quickly recognized as a modern classic of young people’s literature. It won both the National Book Award and the American Book Award and became a part of classroom studies throughout the country. It was later made into a musical play, “Abyssinia.”

Ms. Thomas carried the story forward in two sequels, “Bright Shadow” (1983) and “Water Girl” (1986). (“Bright Shadow” won the American Library Association’s Coretta Scott King Book Award for outstanding children’s books by African American writers.)

In 2001, after publishing several other books for children, Ms. Thomas returned to the story of Abyssinia — by then a doctor known as Abby Jackson-Jefferson — in “House of Light,” a novel directed more toward adults.

Although she had lived in California since she was 10, Ms. Thomas found a never-ending source of literary inspiration in the rural fields and small towns of her native Oklahoma. She sought to draw portraits of black life different from stories in modern urban settings or in the time of slavery.

“I know of black boys and girls who squirm uncomfortably in their desks at the two-dimensional, unrelenting portrayal of young people as either victims of slavery or perennial do-ragwearers hanging out on a stoop next to a garbage can,” she told the African American Review in 1998. “There are black American stories somewhere between slavery and ghetto that also deserve telling.”

Joyce Carol Haynes was born May 25, 1938, in Ponca City. She often missed school while working in the fields with her family.

“Every year when we went out to pick cotton in Red Rock, the women told stories at night to entertain us,” she told the African American Review. “My mother, who was the lead teller, specialized in really scary stories ... The interesting thing is that nobody told the same story twice. Nobody was allowed to.”

In 1948, the family moved to Tracy, Calif., where Ms. Thomas again worked in the fields, picking tomatoes alongside Mexican-born farm laborers from whom she learned to speak Spanish. As a child, she seemed to have an innate awareness of racial injustice, her sister recalled, even in the subtle form of pink-skinned dolls.

“When she and I were children, every year we would get dolls for Christmas,” Krasnovsky said. “She would give hers to me and say, ‘They don’t look like us.’”

Ms. Thomas worked as a telephone operator, married and began raising children before graduating from San Jose State University in 1966. She studied French and Spanish in graduate school at Stanford University, receiving a master’s degree in 1968, her sister said.

For more than 20 years, Ms. Thomas taught in high schools, community colleges and universities, including San Jose State. From 1989 to 1995, she was an English professor at the University of Tennessee.

She published poetry and had several plays produced in the 1970s, but she did not have a major breakthrough until she began writing for younger readers. Among her more than 20 books, Ms. Thomas adapted stories by author Zora Neale Hurston for children and collaborated on several books with illustrators Floyd Cooper and Brenda Joysmith.

In 2003, Ms. Thomas edited and contributed to “Linda Brown, You Are Not Alone,” a book of essays for young people about the U.S. Supreme Court’s 1954 Brown v. Board of Education decision, which declared segregated public schools unconstitutional.

Two of Ms. Thomas’s collections of poetry for children, “Brown Honey in Broomwheat Tea” (1993) and “The Blacker the Berry,” published in 1997 and with different illustrations in 2008, received Coretta Scott King Awards. The title poem of the latter book contains these lines:

“Day couldn’t dawn without the night,” she wrote in the title poem of “The Blacker the Berry.” “Colors, without black, couldn’t sparkle quite so bright.”

Ms. Thomas’s marriages to Joe Harris, Gettis L. Withers and Roy T. Thomas Jr. ended in divorce. In addition to her sister, survivors include a daughter from her first marriage; two sons from her second marriage; a son from her third marriage; seven granddaughters; and two great-granddaughters.

When Ms. Thomas was 11 and her sister 10, they taught a California neighbor’s children to read. The neighbor turned out to be a grand wizard in the Ku Klux Klan, Krasnovsky said, but the children got along with no trouble.

“People will do horrible things to other people, and there is no way to explain it away,” Ms. Thomas told the Tulsa World in 2009. “So I write about these things as a kind of warning, to tell young people there is a darkness in the world ... I know that life can be ugly, but it also can be beautiful.”