Who do you picture when you think of an American farmer? A leathery-handed AARP type who rises at dawn, works the fields all day and returns home when Sally Mae rings the supper bell? If so, you aren't too far off. According to the USDA, the average American agrarian is a white male aged 55 or older. And some studies show that the presence of young farmers, 18 to 35, is actually in decline.

But while they might be dwindling in numbers, young farmers are growing in visibility. And they're a motley, stereotype-shattering crew, for sure.

They're urban, they hold advanced degrees and they're often female. They sprout up in not-so-bucolic places like Brooklyn, Oakland, Atlanta and Indianapolis, and they sometimes work as educators, eco-entrepreneurs, yogis, journalists, filmmakers, activists and doting parents on the side. They're passionate and adventurous. And most notably, they're focused on sustainability and community building.

The following list features 40 American farmers under the age of 40, compiled with help from dozens of people in the farming industry — from farmers themselves to those who help them in the nonprofit sector to those in the media who cover them. They aren't in any particular order (farmer No. 5 isn't necessarily better than farmer No. 15, for example), and in no way should this list be considered scientific. Think of it more as starting point, a beginning to a larger conversation about the collective hope for the future of American farming.

Straw hats off to older farmers — they're the agricultural backbone of this country — but it's also time to acknowledge that Young MacDonald has a farm, too. These 40 up-and-coming farmers are happily working the earth from Roy, Wash., to Tivoli, N.Y., and the crops they grow are just as diverse as their backgrounds. Without further ado, let's meet the gang ...

1) Jason Mraz, 32

"Mraz Farms"

San Diego, Calif.

Singer/songwriter Jason Mraz has produced a bounty of melodic pop-rock songs since hitting it big with his sophomore album, Mr. A-Z, in 2005. (His 2008 follow-up, We Sing. We Dance. We Steal Things., has sold 2.5 million copies.) But reggae- and folk-inflected ditties aren't the only sweet crops Mraz harvests — the Virginia native is also an enthusiastic avocado farmer. After buying five acres in an agricultural area of San Diego, he settled in and began farming the pear-shaped, green-skinned fruits. He also installed a solar-power system on his farm to let the sun fuel more than just his plants.

Mraz has said he eats two to four avocados daily as part of his mostly raw-foods diet, but he's not against making a little green on the side, too. "I do sell my avocados," he told CNN during a 2008 interview. "I mean, they don't have a sticker on them that say that these are from the Mraz Farms, but I moved into an area that all of us are avocado farmers. ... Believe me, our kitchen is just like decked out with them. We're constantly washing them, we're eating them and we're giving them to all our friends."

2) Zoë Bradbury, 29

Valley Flora Farm

Langlois, Ore.

Born onto a small sheep ranch on the Oregon coast, Zoë Ida Bradbury grew up in hoodie sweatshirts and rubber boots — birthing lambs in the spring, watching salmon spawn in the fall, and taming plums, blackberries and tomatoes into canning jars all summer. Her love of food, farming and rural life got its foothold early and carried her full-circle back to her native southern Oregon, where the 29-year-old now runs her own farm, growing mixed produce and berries for local markets with the help of her family and a team of draft horses.

Her work in sustainable agriculture has engaged her with several nonprofits, including Ecotrust, the Agriculture and Land-based Training Association, the Center for Urban Education about Sustainable Agriculture, and the Institute for Agriculture and Trade Policy. She's a regular contributor to Edible Portland and her work has also appeared in USA Today, Oregon Coast Magazine, The Oregonian, Grist.org, Draft Horse Journal and Stanford Magazine. She's also the author of the online blog Diary of a Young Farmer. Before breaking ground on her own land, Bradbury spent three years co-managing Sauvie Island Organics, a diversified fresh market farm where she oversaw production and apprentice training for a community-supported agriculture (CSA) program. 

Bradbury did her undergraduate work at Stanford University, where she studied ecological anthropology with a focus on sustainable agriculture. Her honors thesis took her home to Floras Creek, Ore., and then on to Chile, where she took a hard look at the struggle to sustain family agriculture in both hemispheres. She recently completed her master's degree with a focus on rural development, food systems and community change.

3) Ian Cheney, 29

Truck Farm

Brooklyn, N.Y.

New England native Ian Cheney and his friend Curt Ellis are Wicked Delicate, a Brooklyn-based production company/advocacy project. The duo's latest creation, Truck Farm, is a food/film project starring a gray 1986 Dodge pickup bequeathed to Cheney by his grandfather. This is no ordinary pickup truck: Truck Farm combines "green roof technology, organic compost, and heirloom seeds to create a living, mobile garden on the streets of Brooklyn." A solar-powered time-lapse camera captures the crops' progress as they grow in the truck bed/garden throughout the summer. For $20, New Yorkers can join the Truck Farm CSA program and receive a DVD of the Truck Farm film — plus part of the season's harvest, of course, which includes lettuce, arugula, parsley, basil and more.

Cheney holds both bachelor's and master's degrees from Yale, where he was a co-founding member of the Yale Sustainable Food Project. After graduate school, he co-created and starred in the Peabody Award-winning film King Corn (2007) and directed the documentary TheGreening of Southie (2008). He travels frequently to show his films, lead discussions and give talks on topics of sustainability and agriculture. He's also an astrophotographer and contributing blogger for the Huffington Post.

4) Jason Mark, 34

Alemany Farm

San Francisco, Calif.

Jason Mark, a writer/farmer active in the sustainable food movement, spends half his time co-managing Alemany Farm, a four-acre organic fruit-and-vegetable garden in San Francisco. The farm's mission is to boost food security in low-income communities, provide environmental education to children and adults, and grow green jobs.

The rest of his time, Mark serves as the editor of the environmental quarterly magazine Earth Island Journal. Aside the Journal, his writings have appeared in the San Francisco Chronicle, The Nation, The Progressive, Utne Reader, Gastronomica, E, Grist.org and Alternet.org. He's also a co-author of Building the Green Economy: Success Stories from the Grassroots.

5) Owen O'Connor, 24

6) KayCee Wimbish, 33

Awesome Farm

Tivoli, N.Y.

KayCee Wimbish and Owen O'Connor founded Awesome Farm in January 2008, an idea they first hatched while working together on a vegetable farm. Although they originally planned to start a tempeh business, their concept eventually blossomed from fake animals into real ones, and Awesome Farm was born.

O'Connor and Wimbish currently raise 70 ewes along with their 115 lambs, 1,200 meat chickens and a flock of laying hens. Wimbish, a former second-grade school teacher, is originally from Tulsa, Okla., while O'Connor grew up in Dutchess County, N.Y. Aside from day-to-day farm operations, O'Connor is also working on a project to make grass digestible for humans.

7) Vernay "Pilar" Reber, 37

Sunnyside Organic Seedlings

Richmond, Calif.

Vernay Reber has been working full time in commercial agriculture since the age of 18. She began in huge greenhouses growing wholesale, worked her way up to a pesticide applicator, then eventually to a grower responsible for acres of annuals.

She loved the pace of agriculture, the fact that she could turn out a greenhouse full of plants in a month, and the complex set of problems she had to solve, from getting the plants seeded to getting them onto a truck to be sold. But something inside told her that the system was broken, and that pesticides were a major part of it.

So she enrolled in the University of California-Santa Cruz's agroecology program with hopes of somehow finding work in organic agriculture after graduating — but she ended up back in commercial greenhouse operations. While Reber was working for a company in Salinas Valley, a chemical applicator's wife gave birth to a baby with cornea blindness, then a few months later a woman working in production had a baby born with the same disorder.

Two weeks later, Reber quit and started Sunnyside Organics, where she grows 400 or so varieties of veggie and herb seedlings for 75 garden centers and two farmers markets. In-season, Sunnyside employs six to nine workers, including both at-risk youth and "happy Berkeley kids." Sunnyside has become a catalyst for people to grow their own food, supporting more than 15 school gardens and nonprofits that promote gardening with plant starts.

8) Caitlin Arnold, 24

9) Chandler Briggs, 25

10) Roby Ventres-Pake, 19

Island Meadow Farm

Vashon Island, Wash.

Island Meadow Farm sits on 10 acres of sloping woodland nestled in the middle of Vashon Island, Wash., in the heart of Puget Sound. Its farm stand is a local landmark for small Vashon Island farms and for the island's first-ever CSA program. With more than 100 years of continuous farming history, the property has known many different hands and grown countless pounds of produce. Since becoming "Island Meadow" and a certified organic farm in the early 1990s, it has developed from a Seattle Pike Place Market farm into an island-serving farm stand stocked nearly year-round. It's known for its excellent salad mix and pastured chicken eggs, and recently added a mobile Hoop House.

Caitlin Arnold, Chandler Briggs and Roby Ventres-Pake (pictured above, left to right) came into the 2009 season with a combined six years of experience apprenticing on other Northwest farms. The three manage Island Meadow together, growing a wide array of produce and eggs for the local farmers market, restaurants and, of course, the farm stand. Driven by their desire to provide fresh, healthy food for the community on Vashon Island — and by their rejection of destructive practices driven by convenience and profit — the three are working hard to live up to the Island Meadow name and grow some amazing food.

WANT MORE FARMERS? Check out farmers 11-20 >