Thousands of miles away, their classmates were probably lounging under the sun on sandy beaches, tossing volley balls and knocking back drinks that they might later regret. But on a cloudy Monday morning at Petaluma Bounty, for 24 students from U.C. Berkeley and Portland State University, the closest thing to sand was the dirt trenches they were digging in preparation for a potato planting. The closest thing to a volley ball was the compost they were tossing from pile to pile.

They were at the nonprofit Petaluma farm as part of an alternative spring break trip to learn about food justice, and from the look of things, they wouldn't have it any other way.

"It brings together like minds, those of us who don't necessarily want to spend our spring break in Cabo," said Blake Thomas, a 20-year-old sophomore who was leading the group from Portland after going on a similar trip as a freshman. He and 11 peers looked a little stiff, but were happy to be there after driving directly from Portland to Petaluma in two vans.

Before the trip, he said, most of the students barely knew each other.

"You put 12 students together in a van and hope they get along," the architecture major said with a laugh.

It appeared to be working. Within minutes of arriving at the Petaluma farm on Shasta Avenue, the Portland students were laughing easily with each other and the Berkeley students, who had been working on the farm since Saturday.

Petaluma Bounty, operating as a nonprofit educational farm under the umbrella of Petaluma People Services Center, relies on volunteer help in order to fulfill its mission of providing affordable food to low-income families and seniors, said Suzi Grady, Bounty's program director. A large volunteer group comes through about once a month, providing a much-needed boost by helping out with big, labor-intensive projects like making compost.

"It's great," said Bounty Farm Manager Lennie Larkin. "We have all this winter work to get done, and we're getting it done, and teaching at the same time. These guys are learning the ins and outs of compost."

A group of brightly-dressed girls from U.C. Berkeley were doing so enthusiastically on Monday. Over the last two days they'd become experts in the process, even naming the heaps: the larger one was called Tiramisu, the smaller Lasagna.

"We've been having a great time," said Kayleigh Barnes, a 20-year-old junior. She took a break from moving hay and manure to talk about the program, pitchfork in hand. Barnes came to Petaluma Bounty last year through the same student-led program, called Alternative Breaks. Now, she's helping to lead it. The physics and economics major said she first became interested in farming after taking a food nutrition class her freshman year, where an interest in her own health led to an interest in the health of the environment and society.

Now, she'd like to apply her majors to study the economic impacts of community farms.

Participating students said they'd chosen the alternative spring break for a number of reasons, from "working hard on something that isn't school" to experiencing something new, to meeting new, like-minded people.

After getting to know each other, the 24 students from the two programs got back to work, shoveling dirt, pitch forking hay and transplanting young tomatoes to the background music of red-winged blackbirds and trains chugging by.

Both groups were moving on to other farms the following day, while most of the vegetables they helped plant were destined for food boxes for local families.

Some tomato starts will be sold at an heirloom plant sale on Saturday, May 4. To learn more about the sale or Petaluma Bounty itself, visit http://www.petalumabounty.org.

(Contact Jamie Hansen at jamie.hansen@arguscourier.com.)