Good Oak News

Saturday, December 13, 2008

Book Review: Bringing Nature Home by Douglas Tallamy

This review can be summarized in one sentence: this is the most inspirational book I have read since A Sand County Almanac.

Dr. Tallamy does an excellent job explaining how important landscaping with native plants is to preserving our wildlife. Beginning with a heart-wrenching story about how as a child his favorite little pond full of toads and other wildlife was literally bulldozed in front of him, he describes how development and agriculture have wiped-out and critically fragmented our natural areas, leaving populations of our wild plants and animals on the brink of collapse. Furthermore, invasive plants and insects, most of whom were brought to North America intentionally or unintentionally through the horticultural trade are permanently altering our remaining natural areas and driving our native species to extinction.

As an entomologist, Dr. Tallamy focuses this book on the relationship between our native plants and the critical role wild insects play in the ecosystem. When most people think about insects, they only think of pests like roaches and yellow-jackets, but Dr. Tallamy explains that only 1% of insect species are pests to humans. He describes the fascinating diversity of native insects found in our native landscapes and how these insects regulate plant populations and are a critical food source for the amphibians, reptiles, birds and mammals that we might hope to invite into our backyards.

Chapter 12 describes in detail exactly how various native plant species support wildlife. He continues in Chapter 13 with a catalog of the various families of insects, from beetles to butterflies, with fascinating stories about their lifestyles and striking photos of these truly beautiful though often overlooked creatures.

Finally, Dr. Tallamy offers recommendations as to how people can go about using native plants in their home landscape. This portion of the book is the only one in which I can find fault. First, he doesn't offer enough detail to be useful to most home owners. This is understandable since the book is a powerful treatise on "why" to landscape with native plants, it should be left to other authors to describe the "how" of native landscaping.

More critically, I, and others such as the Wild Ones organization, need to disagree with Dr. Tallamy regarding the use of cultivars of native species. He suggest cultivars as a harmless alternative to truly native plants since they can also feed wild insects. This could not be further from the truth. Many cultivars have been modified in ways that make them less useful to wildlife. For example, columbine is a critical food source for hummingbirds and hawkmoths, yet many cultivated columbines do not produce enough nectar to support these species. Some cultivars that, for example put a lot of energy into developing extra flowers, are less hardy than their wild counterparts and thus are less able to compete with weeds. These cultivars will be from other regions, and thus the plants will not be ideally adapted to local conditions, unlike local-ecotype plants. These factors make cultivated natives a bad choice for landscape use. Furthermore cultivars have the potential to interbreed with the small populations of our truly native plants. This risks "genetic pollution", weakening our native stock, and potentially accelerating their extinction in the wild, rather than aiding and supporting these populations as local-ecotype plantings will.

This minor point aside, this is one of the finest books ever written on the relationship between people and nature and should be on everyone's "must-read" list. Hopefully, future edition will exclude the suggestion that cultivars of native species are appropriate for use in landscaping.