Many large-scale farmers in the U.S. don't care to hear much about climate change. Perhaps that is because agriculture—including livestock-rearing and forestry—is one of the largest sources of greenhouse gas pollution. Nevertheless, American farmers, ranchers and foresters have begun to adopt practices that could cut pollution, or so says a progress report from the U.S. Department of Agriculture on the “Building Blocks for Climate-Smart Agriculture and Forestry.”

Scientific American spoke with U.S. Secretary of Agriculture Tom Vilsack, who has held that job longer than most of his predecessors after stints as governor of Iowa and a presidential hopeful.

[An edited transcript of the interview follows.]

Can American agriculture solve climate change while also surviving it?
Agriculture can contribute to the solution. I say that because there are other industries and other sectors that also have to do their part. But agriculture needs to be part of the solution.

Today, we are 9 percent of emissions [meaning farming and ranching contribute 9 percent of the total U.S. greenhouse gas pollution]. When you include forestry, we're a net sink [meaning that the amount of CO2 sucked in by trees as they grow offsets the amount of CO2 and other greenhouse gases emitted by farming and livestock.] We want to maintain that. But to do that agriculture has to be better at what it does. We need to do a better job of maintaining soil health. We need to do a better job of nutrient management. We need to do a better job with our scarce water resources. We need to do a better job of how we raise livestock and how we graze to maintain sequestered carbon. We need to do a better job of maintaining forests, plant more trees in cities and embrace wood as a building material so that the carbon is stored rather than burned up in forests fires. We need to continue to focus on energy efficiency and renewable energy.

We need to do all that—and agriculture can.

We can double the rate of emission reductions related to agriculture. We can contribute a 2 percent overall reduction compared to 2005 levels, which will help the U.S. meet its Paris goals. All of this will put the U.S. in the position to provide leadership internationally on this issue.

It also opens up an incredible amount of innovation, job opportunities and business growth if we do this right. It's a lot of dynamic activity within agriculture to attract young people whereas before they were discouraged.

Well then, you better hope for lower land prices.
Yes, that's true. But we also have to think about creative ways to participate in agriculture that don't necessarily always rely on land in Iowa that sells for $10,000 per acre. I've talked to vertical farmers in urban centers who want to grow indoors with LED lighting. I've talked to people looking at the top of rooftops to create an urban farming effort. There are community gardens all over the place.

There's also going to be a tremendous transfer of wealth in the not-too-distant future [as aging farmers pass land to their children or others]. We have to instill in those who will be owners of this land a conservation ethic.

But is there a trade-off between some conservation practices, like not tilling farm fields to increase carbon storage, and more pesticide use and water pollution from fertilizers?
Not necessarily, no. Precision agriculture has created a circumstance allowing us to be very precise with the application of inputs [such as fertilizers]. We are becoming more sophisticated in terms of conservation practices. We know how to better use cover crops. We're seeing an expansion of no-till. We don't necessarily have to trade off one for the other.

Why did cover crops that hold soil in place or reduce the need for fertilizers go away in the first place? That was a core part of an older style of farming. Was it a mistake to get rid of them?
I don't know why they have gone but we have to bring them back. Part of it is educating people that incorporating cover crops can lead to greater productivity and more productive soil, which can help the bottom line. We need to find new uses for cover crops to create market opportunities so farmers can pencil it out. We need to make sure that future-risk farmer tools like crop insurance do not discourage the use of cover crops. We're trying to do all three of those.

We have a soil health campaign as part of the Building Block effort. We have announced about $70 million in additional money for soil health and nutrient management strategies. We are working to create markets in the bio-based economy for cover crops and the biomass created through cover crops.

Speaking of a bio-based economy, did the push for biofuels like ethanol from corn make farming's problems worse?
I look at this from a different perspective. I represented farmers during the 1980s when farm families were devastated through foreclosure and the loss of farming opportunity. We knew then that the survival of the family farm somewhat depended on our ability to find alternative ways for crops to be used. I don't think ethanol hurt that.

It's not a bad thing. It's a positive thing from the perspective of creating more stability in the market, creating more jobs in rural areas, converting production into a value-added proposition. The by-products are now being exported around the world [as animal feed]. We even see ethanol being exported.

And farmers have figured out a way for ethanol to be more energy-producing than energy-consuming. That was the knock on ethanol: that it took more energy to create than it produced as fuel. But the most recent studies say it is now two to one, and in the Midwest it's four to one [four units of energy out for every unit of energy in].

The benefit to consumers shouldn't be underestimated, either, because they are paying less for gas. We have taken millions of cars off the road in terms of emissions and cleaner air. So you have to be careful making large-scale judgments and look at it more holistically.

Just as an example, the auto industry is dealing with a real challenge right now. They have to create cars and trucks that will average 40 to 50 miles per gallon. When that rule was developed, the premise was that we'd be converting cars from traditional engines to electric cars. That hasn't occurred at quite the pace anybody anticipated.

So now Detroit automakers are presented with this challenge: How do we meet those [corporate average fuel economy, or CAFE,] standards? One way is through higher-octane fuel mixes—and the best and most efficient way to add octane is through biofuel. It may very well be that biofuel helps us reach CAFE standards that do a better job of greenhouse gas reduction and cuts air pollution.

Farmers helped stop legislative action on climate change early in the Obama administration. Was that a mistake?
Look, a lot of it has to do with how you talk to farmers. Maybe what we've learned from this process was a way to talk about climate change that takes it out of politically charged language into language that farmers receive and are receptive to. We did these Climate Hub surveys. We surveyed 18,000 producers and got 5,000 responses. We asked a series of questions about climate change, and frankly there was very little interest in talking about that.

But a few questions later we asked whether they were interested in weather variability. There was great interest in that. So remove it from politically charged language and talk to people where they are. They are interested in how it affects their livelihood.

There is a long-term impact on how they grow, when they grow, how they plant and when they harvest. If you talk in those terms, all of a sudden it's a different attitude. They want to know the vulnerabilities; they want to know what the mitigation and adaptation strategies are going to be. That's why we set up the hubs.

As farmers become more aware of the opportunities—not just in crop production but also in ecosystem markets—they have the ability to use land in concert with a regulated industry [the electricity sector under the Clean Power Plan to satisfy that regulatory requirement through green infrastructure. There's a lot of opportunity for producers.

We're creating an understandable road map for farmers to follow that plays in a space where they're comfortable and that speaks in a language that doesn't get them defensive.

But is there even a future for farmers on these big farms? Seems like it will all be satellite-guided robo-tractors and drones.
I think there is. The robot and the tractor are not going to make a decision about how to diversify the farming operation. Farmers will make that decision based on data that they accumulate and analyze. Significant thought goes into what to grow, where to grow and how to grow. There will be an analysis of how a changing climate impacts and affects those decisions.

Not all farms are going to be huge. Not all farms are going to be able to afford that driverless tractor. We have created and invested in local and regional food systems to diversify production methods, size of farms, crops being grown and types of operators. That small to midsized operator is not going to be able to sell to local and regional markets if they have to spend a considerable amount of money for machinery.

Traditional notions of farming are being changed, and I think in five, 10, 15 years from now you'll see a much different landscape than you see today.