Dear Readers:

Land can be used to raise cattle, or it can be converted for aquaculture, such as this shrimp operation, and raise many times the weight of meat that pasture would be able to produce. (DTN file photo by Dan Davidson)

In the debate over agriculture's future, people who disagree about almost everything agree on one thing: Sustainability is vital. The problem is sustainability means different things to different people.

Those who favor a more natural, local and organic agriculture -- call them environmentalists, though that oversimplifies the category -- define sustainability as preserving the environment.

Those who favor using technology to boost agriculture's productivity -- call them big aggies, though that too oversimplifies -- stress feeding the world's fast-growing population.

Neither side gives much thought to the third leg of sustainable agriculture's stool -- making money for those who grow the food.

Now and then, though, we encounter someone who grasps the need for all three legs. Meet James McWilliams, a history professor at Texas State University and author of the intriguing new book "Just Food."

McWilliams is an environmentalist, first and foremost, but he's also a fair-minded and original thinker. "Just Food" takes as many swipes at natural-local-organic orthodoxy as it does at corn-soybean-livestock big ag. The author favors both genetic engineering and international trade, though with more conditions than most corn and soybean growers would prefer. His chapter on aquaculture is worth the price of the book.

McWilliams appreciates both the threats agriculture poses to the environment and the need to double food production over the next 40 years. In one chapter, he gently but firmly dismisses organic agriculture as a nice niche system that can't be expanded sufficiently to feed the world and entails environmental risks of its own.

In another, he calls on Americans to cut back drastically on their consumption of meat. There is no environmentally sound way to raise livestock, he argues, and as incomes rise and demands for animal protein rise in developing countries, the world will lack the land and water needed to feed everyone at the rate the affluent world consumes meat. Even producers who disagree will find food for thought in his argument.

Is eating only "local food" the answer to sustainability? Definitely not, says McWilliams. The book is subtitled "Where Locavores Get It Wrong and How We Can Truly Eat Responsibly," and one of its strongest chapters derides the fetish locavores make of "food miles." Transportation accounts for only 11 percent of the energy in food products, he argues.

"Buying local is smart when natural conditions justify the production of local goods," he writes. "Given the stubborn realities of geography, however, chances are slim that one local environment can sustainably accommodate the diverse range of goods that make up a healthy modern diet."

Would eliminating farm subsidies lead to smaller farms and more sustainable farming methods? Yes, McWilliams contends. Yet it seems to me there's an equally good argument that subsidies keep inefficient producers in business. If that's true, eliminating subsidies could hasten the already strong trend toward farm consolidation.

For what it's worth, I know any number of multi-thousand-acre farmers who are glad to take subsidies as long as they're on offer, but think they'd have more opportunity to expand if nobody received subsidies. Reasonable people can differ on whether there are other reasons to end subsidies, but McWilliams doesn't convince me that sustainability is one of them.

What will most interest many producers is the discussion of aquaculture and not just because it's a topic they know little about. Aquaculture, done properly, is not only environmentally sound, McWilliams argues. It can make farmers money.

For example, McWilliams estimates that an unimproved acre of land farmed using aquaponics, a technique in which fish and vegetables grow in the same water, can vastly out produce more conventional agricultural uses of the same land. Using the same unimproved acre to raise grass-fed beef, he argues, would produce but 75 pounds of edible flesh per year, versus 35,000 pounds for aquaponics, plus vegetables. Even if those figures exaggerate the comparison by a factor of two or three, aquaponics still wins big.

McWilliams admits that some types of aquaculture -- especially the big shrimp and salmon farms in some developing countries -- have fouled the environment. But other kinds, including some traditional Chinese methods, are not only ecologically friendly but low cost and low maintenance. McWilliams describes them in detail.

"An aquaculture operation that works according to ecological principles can produce a great deal of edible biomass in a small space with little labor," he writes. "The skilled farmer conducts rather than dictates the performance."

The trick, he says, is concocting a diverse mix of plants and fish that feed each other and recycle each other's waste, thus cutting back on both the need to buy a lot of feed and the problem of waste disposal. In the U.S., McWilliams says, farmers are already raising catfish, tilapia, oysters and mussels using methods environmentalists should applaud.

All in all, this is a book worth reading. Unlike so much of what is written about agriculture these days, it takes into account all three of the competing demands of sustainability and does so with rationality, balance and fidelity to evidence. You may not end up agreeing with McWilliams that he's found the "Golden Mean," but you will admire the conscientiousness with which he pursues it.

**

As always I welcome your feedback on this letter and your suggestions for how DTN might serve you better.

Sincerely,

Urban

Urban C. Lehner

Editor-in-Chief

DTN/The Progressive Farmer -- A Telvent Brand

9110 West Dodge Road Suite 200

Omaha, NE 68114

urban.lehner@dtn.com

Phone: 402 399 6440

Fax: 402 390 7187

(CZ/KM)

© Copyright 2010 DTN/The Progressive Farmer, A Telvent Brand. All rights reserved.