Nathan Kleinman and Dusty Hinz met during the Occupy movement, camped out on the concrete outside City Hall.

Four years later, they're still organizing, but in a more verdant setting: a peaceful patch of farmland off a rutted dirt drive outside Elmer, N.J.

Their goal now: Harness the power of the crowd for the future of farming.

Their organization, the Experimental Farm Network, aims to connect plant breeders with gardeners and citizen scientists around the world to develop sustainable, perennial food crops that can flourish in the face of climate change.

Kleinman, a longtime amateur horticulturist, had been seeking out and growing local heirloom seeds long before Occupy.

But after helping lead the Occupy Sandy hurricane-relief effort, which mobilized thousands of volunteers, he realized his organizing skills could be applied to any number of issues - including plant breeding.

"It made me realize that there's a lot of potential to do something on a large scale that's really important, that can have real results with volunteers," he said. "We've got a few hundred people now around the country collaborating. We'd ultimately like to get thousands of people working on this."

Kleinman, 33, of Elmer, and Hinz, 28, of Westville, N.J., have been sending out dozens of seed packets for gardeners to test.

Early projects include a popping chickpea - like popcorn, but with far more protein - that's being assessed for viability in varied climates, and a perennial grain sorghum they're asking volunteers to cross-pollinate with annual varieties.

It's a way to speed up a process that could otherwise take years, Kleinman said: "Say you're trying to breed early eggplants for northern climates, you might make a bunch of crosses and end up with tens of thousands of seeds. But you may only have space and time to grow out a few hundred plants and evaluate them."

With hundreds of collaborators, "you increase that potential of finding that one-in-10,000 seedling that has all the characteristics you're looking for."

It sounds quixotic, especially as neither man has a science background. (Both political science majors, they're supporting themselves through a patchwork of jobs while the farm gets off the ground.)

But Hinz cites as a precedent Luther Burbank, a pioneering breeder responsible for many varieties still grown today who was nonetheless criticized by scientists of his time.

Besides, Hinz's goal with the Experimental Farm Network isn't to advance his own projects but to connect others. A core part of the plan is creating a social-networking platform where scientists can connect with collaborators. He hopes the website, experimentalfarmnetwork.org, will be fully functional by fall.

"It's not necessarily about being a scientific expert," Hinz said. "It's about being organizers."

The project is attracting interest from plant breeders such as Carol Deppe, a scientist and author in Corvallis, Ore. She produces varieties she knows do well in Oregon, but up until now it's been hard for her to assess whether the plants are also viable in other parts of the country.

She said universities often circulate new varieties to one another, and plant breeders may send a few seeds out to friends around the country to test in different climates. But until now, no one has undertaken organizing this work on a large scale, she said.

"For those of us who are freelance plant breeders, either working for small seed companies or we are small seed companies, there hasn't been anything like this," she said.

She's preparing to send the Experimental Farm Network 40 pounds of one of her own varieties, Cascade Ruby Gold flint corn, to distribute to volunteers next spring. The grinding corn, good for polenta and corn bread, is cold-resistant, easy to grow, and thrives in places like the Oregon coast, where corn has not been a practical crop. Now, she wants to know exactly where else it will flourish.

"It's bred to be the ideal survivor's crop," she said. "When I hear about a natural disaster, I immediately think, 'I wish they had my corn.' But I don't even know if my corn would grow there."

Steven Cannon, who works with the U.S. Department of Agriculture research service out of Iowa State University, has been participating in the network in his spare time.

He said the model was a throwback to how early crops were domesticated and improved: by farmers independently growing crops and saving seeds from promising plants to share and plant again.

"They're focusing on crops that most of the commercial breeders aren't going to touch, but they could still be very important," he said. "For example, sorghum is important in a lot of African countries, and it tends to be really drought-tolerant and high yielding. It's not a major crop in the U.S., but it could be very valuable."

On the farm, Kleinman and Hinz have a greenhouse filled with a few hundred varieties: a perennial kale they want to continue crossbreeding, a wild perennial beet they think has potential as a food crop, and asparagus starts they hope will be pest-resistant.

They're also growing yellowhorn, a Chinese tree with edible leaves and flowers and seeds that can be pressed for oil.

"Nobody's really growing that as a food crop," Kleinman said. "But I've read that it has the potential to produce 800 gallons of oil per acre, which is huge, more than soybeans. If we had big plantations of this, we wouldn't need to grow acres and acres of soybeans in really environmentally destructive ways."

These are not, yet, major cash crops. So far, the effort has been supported with crowdfunding and through sales of seeds like a broccoli rabe turnip that Kleinman and Hinz found growing wild on the farm and that they have been working to domesticate.

For now, there are plenty of people willing to pitch in free.

Bri Barton, 27, garden manager at Historic Fair Hill Burial Ground in Philadelphia, met Kleinman and Hinz at Occupy Philly, and later joined the board of the Experimental Farm Network. She's been working to increase seed supplies of unusual varieties of corn and beans, as rare seeds are often available in small quantities.

She's not sure what will come of the work just yet.

"That's up to whoever participates, and I think that's one of the coolest parts of this network," she said. "Anyone who wants to can bring a project to it."

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@samanthamelamed