BERKELEY, Calif. — Natasha Boissier did not expect an epiphany while pushing her baby’s stroller exhaustedly around the neighborhood. But eyeing her neighbors’ yards, Ms. Boissier began noticing the abundance of fruit trees — and how much of their succulent bounty wound up on the ground.

“There was all this fruit going to waste,” she said of the apples, pears and plums in her midst. “It seemed like such a natural way to deal with hunger.”

Thus was born North Berkeley Harvest, part of a small but expanding movement of backyard urban gleaners — they might be called fruit philanthropists — who voluntarily harvest surplus fruit and then donate it to food banks, centers for the elderly and other nonprofit organizations.

In an era in which fruit canning, drying and preserving are for many no longer everyday skills, harvesters like Ms. Boissier, a 40-year-old social worker, are bringing a new spin to the concept of U-Pick-’Em. A renewed emphasis on locally grown organic foods, along with higher food prices and increased demand at food banks, has inspired a new generation of community harvesters to search for solutions in their backyards.

“Farmers markets are great for those who can afford to spend $2 on a peach,” said Aviva Furman, 54, whose year-old Community Harvest of Southwest Seattle also offers canning and pruning classes. “But a huge percentage of Americans can’t afford the two cups of fruit a day recommended by the government.”

The concept of gleaning, or collecting a portion of crops on farmers’ fields for the needy, before or after harvesting, goes back to ancient cultures. But it has more recently been taken up by people like Joni Diserens, a 43-year-old program manager for Hewlett-Packard and founder of Village Harvest in Silicon Valley. Ms. Diserens uses sophisticated databases and remote telephone answering systems to track the group’s 700 or so volunteers, 40 receiving organizations, 1,000 fruit-inundated homeowners and, on a recent Tuesday, 780 sticky pounds of French prunes.

They rescue people like Diane Leone, an artist whose property south of San Jose, Calif., contains some 40 unpicked fruit trees, from bees, squirrels, the occasional wild boar and other creatures that gorge on fallen fruit.

“You feel like you’re actually doing something,” Diana Foss, 44, a former astronomer who is now a stay-at-home mother, said as she was sorting plums and prunes recently in Ms. Leone’s backyard. “You pick a piece of fruit and know that someone’s going to eat it.”

The group’s car pools fan out to places like the Community Services Agency in Mountain View, which operates a food pantry that serves a large Russian, Hispanic and Asian population. “Their speed is astonishing,” said Laura Schuster, the nutrition programs director. “They’ll call and say, ‘Hey, we’re hitting an orchard in San Jose.’ Then they walk in with 1,000 pounds of plums.”

Ms. Schuster added: “We always worry about nutrition. When we get the fresh fruit, we worry less.”

Over the last decade, organizations like Feeding America, a nonprofit agency that distributes food to more than 200 food banks around the country, have introduced more fresh produce to respond to high rates of poverty and obesity and a lack of access to nutritional food in low-income neighborhoods. About 18 million pounds of fresh produce was distributed nationally 10 years ago, said Rick Bella, the director of food purchasing. This year, that has grown to 150 million pounds, 30 percent of it donated by corporations and individual farmers.

But affordability continues to be an issue, Mr. Bella said, which is where the fruit philanthropists come in. “It’s a shame to say, but a package of Twinkies per pound costs a lot less than a pound of fresh apples,” he said. “Backyard gleaners make a difference.”

Amy Grey, a graphic designer and mother of two in Moscow, Idaho, became a harvester after inadvertently growing 200 heads of lettuce in her backyard. “I didn’t know you weren’t supposed to plant the whole packet of seeds,” Ms. Grey said. “We have friends,” she added, “but we don’t have that many friends.”

A local food bank was so receptive that Ms. Grey and several volunteers joined with a local environmental group before striking out on their own. Her 50 or so gleaners picked 10,000 pounds of fruit last year, including more than 2,000 pounds of cherries, despite June snows. “It’s different than dropping off cans,” Ms. Grey said. “It’s really about tying the community together.”

Backyard harvests gleaned for the common good echo the Victory Gardens of World War II, when mandatory food rationing resulted in citizen gardens, said Amy Bentley, an associate professor of food studies at New York University and the author of “Eating for Victory.” During the war, Dr. Bentley said, the private yard became “a place of civic obligation.”

Frederick L. Kirschenmann, a fellow at the Leopold Center for Sustainable Agriculture at Iowa State University and president of the Stone Barns Center for Food and Agriculture in Pocantico Hills, N.Y., said that with increased food costs, “we are seeing changing attitudes about our food system.”

“People are becoming more engaged,” Dr. Kirschenmann said, “whether growing their own food or being part of community efforts.”

A survey this year by the National Gardening Association predicted a 10 percent increase in the number of people growing vegetables at home. “Sticker shock is prompting many folks to grow, if not a produce department in their backyards, then at least a salad bar,” said Bruce Butterfield, the research director.

For the St. Mary’s Food Bank Alliance in Phoenix, the abundance means a brigade of citrus volunteers from January through March, picking 1.4 million pounds of oranges and grapefruit from Sun City and Surprise. The fruit reaches thousands of people, from those at domestic violence shelters in Tempe to those on the Havasupai Indian Reservation in the Grand Canyon.

In Los Angeles, three “social activist” artists who call themselves Fallen Fruit have mapped neighborhood fruit trees and sponsored public “fruit jams,” said David Burns, a founder.

“The L.A. we experience is mostly mediated through windshields and cellphones,” Mr. Burns said. “So it was surprising to find out how many fruit trees hang over alleys, sidewalks and parking medians in neglected corners of the city.”

Ms. Boissier, who grew up on Park Avenue in Manhattan, drives through the Berkeley hills in a Toyota hybrid loaded with apples and ladders, helping out homeowners unable to keep up the pie-baking pace, even with convection ovens, and relieving them of the guilt of waste.

In the bustling kitchen of the Bay Area Rescue Mission in Richmond, Calif., a shelter serving more than 800 people a day, the apples would soon be transformed into pancake toppings, apple butter, cider and cobblers.

Roy Hunderson, homeless for four years, prepares meals in the kitchen. “The fresher the fruit, the better it is,” Mr. Hunderson said. “If I had a backyard with fruit going, I’d bring it here too.”

Food Banks Finding Aid in Bounty of Backyard