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The Genus Betula: A Taxonomic Revision of Birches

The Genus Betula cover

The Royal Botanic Gardens, Kew have published a series of excellent monographs – in-depth botanical books about a single genus or occasionally a few closely related genera. While all are of high quality (and we have them all in the Miller Library), none match the level of enthusiasm displayed by the authors of “The Genus Betula: A Taxonomic Revision of Birches.”

While most monographs are written by intensely academic researchers, one of the co-authors of “Betula” was a garden designer (Kenneth Ashburner), whose passion was for the living trees in a designed setting. His frustration with the confusion in the nursery trade was a driving force in his authoring this book. His co-author, Hugh McAllister, is a more traditional tree botanist (having written an earlier monograph on Sorbus, the mountain ashes), but demonstrates his own passion as he marvels over a genus that spans the colder parts of the northern hemisphere.

The result is a book will serve a wide range of interests. It is excellent for learning more about the many birches in the arboretum (at least 50 known taxa plus many hybrids and unknown species). Each species is described with the expected botanically precision, but there is much, much more, including its ethnobotany and natural history, cultivation techniques, conservation status, and identification guides.

This book is also handy for shopping. Recognizing that buyers are drawn to white-barked saplings leads to a discussion of comparative “whiteness” of selections and the age of achieving whiteness by popular nursery stock. The authors are keen about other colors, too, encouraging the use of copper to orange or even pink colored forms of Betula utilis. The remarkable peeling habits of different species are praised as well, as is the showiness of the catkins and fall color.

One of the best features of these Kew monographs is the uniformly superb illustrations. In addition to high quality photographs and numerous diagrams, paintings by Josephine Hague make “Betula” a very beautiful book, too.

Excerpted from the Summer 2016 Arboretum Bulletin.