RENEE MONTAGNE, HOST:
Clean, safe food, it seems like growing it would be good for the environment. But farmers here in California are proving that can be just the opposite. Much of the spinach and lettuce Americans eat comes from California, and a deadly outbreak of e. coli a few years ago, involving spinach, put many farmers on a single minded focus on food safety - which, in turn, has hurt wildlife and polluted streams and rivers. NPR's Dan Charles made a trip to where the spinach is grown to explain why.
DAN CHARLES, BYLINE: I'm taking a little tour of the Salinas Valley on California's central coast with Daniel Mountjoy, an ecologist.
DANIEL MOUNTJOY: I just, I love the drive down through here.
CHARLES: There's are mountains to the east and the west, but the valley, miles wide, is as flat as high-tech, field leveling equipment could make it. The Salinas River meanders down the middle.
MOUNTJOY: It's off to our right, right now. Anywhere where you see, sort of, taller row of trees is probably where the river is. Yeah, that far side there.
CHARLES: But most of what we see is mile after mile of fields. Some bare, ready for planting, some with rows of green leaves, just emerging from brown dirt. This is one of the country's biggest sources of fresh lettuce and spinach. It's often called America's salad bowl.
And for the past 40 years, this valley has been the scene of a struggle to find a balance - between some of the most intensive farming in the world and what's left of nature. When Daniel Mountjoy first came here as a student, almost 40 years ago, farming had already taken over.
MOUNTJOY: One of my professors brought us out on a field trip.
CHARLES: This professor had invented some of the first chemical herbicides that farmers used to kill off weeds.
MOUNTJOY: He was very proud of the fact that farmers had been able to eliminate and restrict all non crop vegetation from the farms, and pointed out that you could tell a good farm from a bad farm by that fact that there was, from fence post to fence post, the only thing that was growing was the crop.
CHARLES: Mountjoy, though, found it bleak. Ecologically, it was impoverished, barely any food or shelter for insects, or the birds that feed on the insects, or bigger animals that need even more space. Also, when it rained, soil and fertilizer washed straight into drainage ditches, streams, and the Monterey Bay.
Daniel Mountjoy became part of a movement to change that. He went to work for the environmental conservation side of the U.S. Department of Agriculture. And for almost 20 years, part of his job was encouraging farmers in this valley to create a greener, more diverse landscape.
He stops the car to show me an example: a drainage ditch, almost two miles long. Ten landowners agreed to cover the bare dirt banks of this stream with grass. It held the soil in place and captured fertilizer runoff that would otherwise have polluted the bay.
MOUNTJOY: And so it was a green swath all the way through the valley, and it represented a real advance toward water-quality protection.
CHARLES: In other places, farmers took hillsides, or the margins of fields, and planted vegetation that was specifically selected to be a good home for insects - especially insects that actually help farmers by gobbling up pests like aphids. And there were even visionaries who talked about creating corridors of wildlife habitat across the valley, so animals could migrate from the mountains on one side over to mountains on the other.
Then six years ago, there was a food safety crisis in the Salinas Valley. Bags of pre-washed spinach from this area, killed several people and sent hundreds more to the hospital across the country. The leaves had been contaminated with a deadly kind of E. coli bacteria.
Those microbes can be carried into a lettuce or spinach field by wild animals - even little mice that might find shelter in grass along drainage ditches. The leafy-greens industry was determined to eliminate that risk. And Mountjoy watched his green swath disappear.
MOUNTJOY: The farmers, increasingly, were being told, this is a potential risk to your operation. And one by one, the growers came in and sprayed it with herbicide, knocked out the grasses, returned it back to its bare ditch condition.
CHARLES: It wasn't just this ditch. Across the valley, trees, grass, and hedgerows disappeared. So did ponds that might attract ducks and geese. Farmers built fences along the Salinas River channel, to keep wildlife that live there from crossing into fields.
That campaign has been a success, in one way. In the last few years, there have not been any more big national outbreaks of disease traced to leafy greens. But many environmentalists, and even some vegetable growers here, think that this campaign for food safety has also been reckless and sometimes needlessly destructive.
BOB MARTIN: People know me as a fighter; I'm not going to give in to everything.
CHARLES: Bob Martin has grown vegetables here his whole life. He runs Rio Farms near King City. He doesn't call himself an environmentalist, but when food safety experts from the big food buyers told him to clear away vegetation on hillsides, he refused.
MARTIN: It goes against my nature to have the scorched earth policy. To have bare banks, so every time it rains you've got to bring the bulldozer and push that dirt back up. It makes no sense. Erosion control is a healthy thing and it's necessary.
CHARLES: What really gets him frustrated are demands that seem contradictory, or even self-defeating. For instance, he always liked having hawks or owls around, because they control the mice. But now, he says, those birds are seen as a threat, too.
MARTIN: I mean, it's frowned on to put up an owl box. The food safety people, they go, the owls poop, too. OK. Well, but they - what do they poop? They poop the mouse that you didn't like in your salad. It's - I mean it's everything we do is conflicting. It seems like we can't do anything right.
CHARLES: In fact, even some of the people who came up with the new safety guidelines admit that they don't know, for sure, which of their anti-wildlife rules really do make food safer. Mark Borman, who's president of Taylor Farms, one of the biggest sellers of fresh leafy greens in the country, says they were just the industry's best guess for what to do to prevent a repeat of the great spinach disaster of 2006.
MARK BORMAN: When you're kind of faced with an unknown, which the industry was faced with six years ago, you know, you throw everything and the kitchen sink at it, right.
CHARLES: But then you try to get a little smarter, he says. And in fact, industry-funded groups and the government now are doing research, trying to figure out which animals really are a serious threat to food safety - and which ones might actually be helpful, because, for instance, they prey on mice.
That research is not done yet. But Daniel Mountjoy says he thinks the pendulum is already swinging back a little bit. He now works with a non-profit group called Sustainable Conservation, and he's been meeting with farmers, environmentalists, and regulators. Together, they're looking for creative ways to manage agriculture in the Salinas Valley so that it's safer and also greener.
MOUNTJOY: Environmental protection, food safety, economic profit, you know, all of those have to go together.
CHARLES: So can you have it all.
MOUNTJOY: I think so. I firmly believe so.
CHARLES: In fact, he says, the salad greens industry of the Salinas Valley needs all of that to survive.
Dan Charles, NPR News.