The sixth edition of the National Geographic Society's "Field Guide to the Birds of North America" was published in November 2011. While closely resembling Edition Five, this sixth iteration is a significant improvement not only of National Geo's efforts, but also of birding field guides in general. Some very welcome features have been added.

The National Geo bird guide on my shelf is the third edition. Jude, my wife and birding companion, uses the fourth. The book first was published in 1983. A million and a quarter of that edition were printed, so I'm sure I had one. If I remember correctly, it fell from my jacket pocket during a spring Texas trip, landing in a puddle in a thicket. When it dried, the pages were clumped together; it was a brick.

The National Geo in 1983 was what many of us considered a significant improvement on the Peterson guide, the standard then. The National Geo illustrations had perspective; they were more life-like. The range maps were on the pages facing the bird illustrations, not tucked in the back of the book as the Peterson maps were. There was more text. And, it was the new thing. The early 80s was a thin time for field-guide choice. The numerous and varied choices we have today were not available then.

The new edition closely resembles that 1983 issue in size and general appearance. The artwork, much of it new with other plates freshened, continues to set a high standard. The maps are new, redrawn to include more information about migration. The introductory text has been shortened; it's better, informative while concise.

The best features of this edition are brand new. In most guides, the photos and text are separate, illustrations on this page, text on the facing page. To see what you just read about, you look to the facing page. National Geo 6 has added to the illustrations brief text to highlight salient features of the bird illustrated. Roger Tory Peterson scored big when he introduced those little arrows that pointed out the particular colors or shapes that separated one species from another. The new National Geo has replaced arrows with text. It's a wonderful idea. You wonder why it took publishers so long to think of it. Here, you have the illustration accompanied by what amounts to very brief CliffsNotes on that bird.

Next, the book has labeled thumb notches on outside page edges to give you rapid access to the sections of the book devoted to seven major bird families: hawks, sandpipers, gulls, flycatchers, warblers, sparrows, and finches. The notches don't open every door, but they put you immediately in the appropriate hallway.

Even better is an alphabetical list of species inside a front cover foldout giving page numbers for text and illustration. There is an index in the back of the book as well, but this easily accessible name-only alphabetical list will save a lot of time. Book contents are presented in the usual taxonomic order, which has a learning curve a whole lot different than the alphabet.

There also is a set of drawings spanning inside front and back covers that show one each of various bird shapes and colorations. If you see a bird but have no idea of where to begin your search in this book, a quick review of these drawings, which include page numbers, could save you a lot of page turning. Speaking of page turning, the family name for each group of birds is printed in the outside top corner of each page. This also makes things easier and faster to find.

When the Sibley guide was published about a dozen years ago, it was the exciting new kid on the block. Sibley's artwork was very good, and more individuals of each species were shown. I liked it then, and still do. But, National Geo 6 is now my default go-to guide. It is the design innovations that push this book to the front. You will not find a field guide that gives you better and faster access to the information it contains.

I have one complaint: the range maps. This is a gripe I have about almost every field guide ever printed: the colors chosen to denote various seasonal distributions invariably include some combination of subtle shades of green, yellow, red, pink, gray, and brown. In the case of the National Geo the problem is green and yellow. Ten percent of men of northern European descent – and that's a lot, including me -- have a color perception problem that centers on green and red. In National Geo 6, I cannot distinguish one shade of yellow / yellow-green from another, and the "red" distinguishing spring/summer breeding range looks green to me. Many colors and textured patterns are available to book designers. You don't have to choose colors that a substantial number of birders can't use. Someday, a smart publisher will figure that out.

In the meantime, smart publishers everywhere should take a careful look at National Geo Sixth Edition. It has raised the bar for birding field guides.

In a day or two I'll write about a conversation I had with Jonathan Alderfer, a principal in the creation of these guides since the first one was published in 1983. We visited about how such a book is created.