"Some Luck," the first of a planned trilogy by Pulitzer Prize-winning author Jane Smiley. (Knopf)

Some Luck ,” the engaging first volume of Jane Smiley’s planned trilogy, is a sweeping story that spans 33 years, three continents and a generation of children on an Iowa farm. Over the course of the novel — already longlisted for the National Book Award — most of the children will leave the farm just as surely as the rest of the white rural Midwest will pack its bags. Smiley delivers a straightforward, old-fashioned tale of rural family life in changing times. Her no-muss, no-fuss storytelling, if unsurprising, is also frequently subtle, wry and moving.

Among her many novels, Smiley has written a powerful chronicle of Midwestern farm life in her Pulitzer Prize-winning “A Thousand Acres” and a clever satire of academic life at an agricultural studies university, “Moo.” “Some Luck” explores many more characters and a far longer stretch of time — hence its structure, tidy as a well-planted cornfield, one chapter devoted to each year from 1920 to 1953. Smiley gives all the family members their own scenes.

The story opens with the patriarch, Walter Langdon, walking his Iowa farm. It’s 1920, and Walter, recently home from World War I, contemplates his first-born son and his “perfectly graceful” young wife, Rosanna. Walter’s life is his farm and his family. The Langdons both come from farming stock — his English, hers German — and know constant work, much of it described here with the precise attention that grants labor its own grace.

The family members’ fortunes mirror the fortunes of the nation, with allowances for personality and luck. The eldest child, Frank, has movie-star looks, a singing voice to match and a quick mind. He touches everything he’s been forbidden to touch: His father repeatedly takes an ineffective strap to him, as generations of American fathers have done. It’s no surprise that Frank is a merciless bully to the next in line, Joe,who is quickly pegged the whiner of the family. The boys and their younger siblings are indoctrinated in the virtues of work from an early age and enchanted by their one-room school.

The Langdons are spared the Depression’s worst weather, but wells dry up and neighbors flee. Even in good years, buyers offer precious little money for their crops. Smiley suggests the culture’s small-mindedness and bigotry along with its generosity and sacrifice. She does not neglect the radical movements that flourished in the Midwest: Rosanna’s sister Eloise marries a communist, moves to Chicago, takes a Trotskyite line and follows news of Stalin with mounting dismay. Rosanna tries out religions: Raised Catholic, she takes the children to see evangelist Billy Sunday, who terrifies them.

Smiley depicts isolated farm life with such precision that readers can understand exactly how little boys help their father shorten lambs’ tails, and how Rosanna copes when she must deliver her baby alone (“Her belly looked as though it was shivering and rippling, but, then, so did the curtains”). The author enumerates acreage yield and recipe ingredients with equal attention, and she describes an Italian prostitute’s business as specifically as the techniques of the Army snipers who pay her. It is especially satisfying to hear a powerful writer narrate men’s and women’s lives lovingly and with equal attention.

The American drift from farm to town has engaged many fine contemporary writers: Annie Proulx, Marilynne Robinson and Larry Woiwode have covered this territory with more lyrical and daring narratives. Smiley’s version is weirdly bold in a different way, stubbornly telling the story with the same kind of unadorned (and sometimes unspoken) language its characters use. This can be frustrating — to cover so much time and space, the novel often resorts to neat and distanced summary, especially of emotion. When the narrative tells us, seemingly without irony, that “Frank liked everything about the army so far,” the reader thinks: Really? Everything? But Smiley has written a great deal about what novels should be (she champions narrative breadth and moral clarity) and she knows what she wants here. If this novel avoids certain realities the way the Langdons avoid difficult subjects at the supper table, it nonetheless depicts plenty of suffering.

As the story comes to a close, Smiley drops clues about what may lie ahead for the next generation of Langdon children — the adult Joe’s experiments with a new kind of fertilizer, for example, may have profound implications for American agriculture and for the planet, to say nothing of his own fortunes. But how these tantalizing details come to fruition are another story . . . or, more precisely, two more volumes of a Smiley trilogy.

Sayers, a professor of English at Notre Dame, is the author of six novels, including “The Powers.”

Jane Smiley will be at Politics & Prose Bookstore, 5015 Connecticut Ave. NW, at 7 p.m. Monday. Call 202-364-1919.

SOME LUCK

By Jane Smiley

Knopf. 395 pp. $26.95