Has it come to this? Do careful shoppers really need to bring a book to the grocery store to help pick their way through the flood of labels claiming “100 percent organic,” “made with organic ingredients,” “natural,” and many others? Yes, says a new book titled A Field Guide to Buying Organic, which offers an aisle-by-aisle guide to a wide range of labels and tips on when they’re worth the extra cash you usually pay.

When I read through the book, though, I found it doesn’t quite deliver on its promise. It’s certainly a thorough and even-handed examination of labeling and standards, and offers lots of comparisons of, say, pesticide residues found in various conventional vs. organic produce. But it’s a bit lacking in new and useful practical advice. (This is partly because of the cumbersome way they separate tips for health-oriented shoppers from tips for environmental shoppers or socially conscious shoppers.)

The exception for me was an eye-opening chapter on dairy products: how they’re regulated; the kinds of contaminants that regularly show up in conventional and organic milk; why organic butter might be especially worth the price; and many other troublesome issues, such as somatic cell count (yikes).

The authors conclude that buying milk from smaller farms—organic or not—is probably worth the extra money, because they do a much better job of caring for cows, preventing infections, and restricting drug and hormone use. (This is especially in true in western states such as Washington, which tend to be dominated by large, industrial-size dairy operations.)

And a recent article in Grist on organic food prices is worth a read. It looks at the history of the organic movement, what share of the marketplace organics need to capture before prices come down (one-third, according to one study), and the contradictions inherent in the price issue, like: Is organic food too expensive or is conventional produce too cheap?