Forest Park is one of the largest patches of urban wilderness in the United States, and the Victorian homes and gardens nearby create an air of Tolkienesque enchantment. Right around here in fact, one of Tolkien's heirs labors in a century-old house.

"I agree with Tolstoy that the best way to tell a story is invisibly," Ursula K. Le Guin says. "But I also hear what I write, and I think if you can't read it out loud, there's something wrong with it."

It's hard to find a literary career as varied as Le Guin's. At 79, she's worked for half a century on the ever-shifting frontier between literary and genre writing, a line she has helped redraw with her elegant prose.

Le Guin has long been celebrated as a pioneer of young adult literature. Just two weeks ago she won a sixth Nebula Award for her YA novel "Powers." With last year's death of Arthur C. Clarke, she is also arguably the most acclaimed science fiction writer on the planet. But she's more.

Her 1968 novel, "A Wizard of Earthsea," concerned a school for wizards; the National Endowment for the Arts made the book a selection of its program the Big Read.

"I think Le Guin is vastly underrated by the critical establishment, which continues to stereotype her as a genre writer," says former NEA Chairman Dana Gioia. "She's become a deeply serious writer without losing the vitality and the excitement of popular literature."

Her admirers include Salman Rushdie as well as the generation working genre's borderlands: Michael Chabon, Neil Gaiman, David Mitchell, Jonathan Lethem and Kelly Link.

For all this, she is in a curious position: She's achieved these things almost entirely on the basis of work now three and four decades old. "She was the big thing for almost 20 years," said Donna White, author of "Dancing With Dragons: Ursula Le Guin and the Critics." "The 1970s and 1980s were her big decades; she was revered by scholars. But now people have moved on."

Her status is further confused because of the variety of fields -- YA, fantasy, science fiction, essays -- in which she writes.

But don't count Le Guin out. Her recent "Lavinia," a novel set in the world of Virgil's "Aeneid," was compared by Publishers Weekly to Robert Graves' "I, Claudius."

Le Guin's early years help explain her abiding concern: Is there such a thing as a stable human nature? She grew up in Berkeley, the daughter of Alfred Kroeber, a founder of modern anthropology, and Theodora Kroeber, author of "Ishi in Two Worlds," about an American Indian who had outlived his tribe. Her childhood, which included summers at a family ranch in Napa, was full of reading, storytelling and visits from European intellectuals and Native Americans.

"I was privileged," she says, "to know the kind of people that most American kids, most bourgeois white kids, don't." She was raised "as irreligious as a jack rabbit."

Eric Rabkin, who teaches at the University of Michigan, sees her work as profoundly shaped by her exposure to alien cultures as well as her father's ambition to find as specifically as he could the time and place from which Western civilization had sprung.

"There's a kind of romance to that view," Rabkin says. "That once upon a time, the worst antagonisms were merely inter-familial -- that basically we're all alike and trustworthy. And I believe she grew up in a family in which that was considered not a fantasy but a scientific fact."

As a kid, Le Guin thought science fiction was corny.

"When I was about 11," she recalls, "my brother and I used to buy Astounding [and other pulps]. We sneered at a lot of it. We were pretty arrogant kids."

Then, around age 30, a friend drew her attention to Cordwainer Smith and Theodore Sturgeon. "I thought, 'Oh, look at that. That could be fun.' "

Some of the SF faithful hold it against Le Guin that she prefers Borges and Virginia Woolf to what she calls the "white man conquers the universe" tradition of Robert A. Heinlein. Yet science fiction clearly fit this daughter of anthropologists. Here, she wrote, "All alternatives are thinkable. It's not a comfortable, reassuring place. It's a very large house, a drafty house. But it's the house we live in."

From the late 1960s to the early 1970s, Le Guin went on a streak inspired by her interest in thought experiments and a Taoist concern for equilibrium.