Tallamy Book: Bringing Nature Home.

A very interesting book which provides a biological/evolutionary reason for gardening with native plants. The central ideas include: (1) the coevolution of plants and insect herbivores within ecosystems, (2) the resulting biodiversity, (3) the influence this has on the biomass available to higher consumers in food webs, (4) the need to support biodiversity by using plants that native insect herbivores can use and hence (5) the need to use native plants in gardening.

Since Tallamy is trying to make an academically derived point to a wide audience, he might be excused for some simplified reference to gardening. "For the past century we have created our gardens with one thing in mind: aesthetics." (p 286) Many gardeners have been aware, for some time, of some of the issues he raises; for instance, the several dangers of monoculture. Hence, perennial gardening is likely to include some or all of using large numbers of species, expanding flowerbeds at the expense of lawns and using close and 3-dimensional plantings. Also there has, for some time, been a strong interest in ecological and organic ways of doing gardening, particularly by using native plants.

I certainly have an immediate sympathy with Tallamy's call to secure and restore habitat to local wildlife and, after reading the book, a greater appreciation for promoting this by using native plants. It certainly seems laudable to restore habitat by using native species in gardens on suburban properties. I'm also quite relieved to read that Tallamy is not calling for the prohibition of alien plants in gardens, but rather for notably increasing the use of native ones. I accept the need for reasonable choices to be made, and also assume there is/will be disagreements over what is reasonable.

The major concern I have with Tallamy's recommendations, involves the size of typical suburban properties (at least around here) and some of what he talks about putting on them. "Most yards can support many more trees than they currently do, particularly near the borders of the property, - - - ." (p 129) Tallamy also talks about the importance of choosing the right kind of tree (p 137), apparently with maximizing insect herbivore biodiversity in mind. But large trees can also present particular problems on small suburban lots, e.g. shading out neighbor's property, cost of maintenance by arborists, etc.. I can only assume that compromise would be required over the issue of large trees, even though this may reduce the ultimate amount of maintainable suburban biodiversity. I do agree with Sempervirens on the desirability of using native shrubs and small trees.

I would also see property size as a factor in the issue of potentially messy native plantings. In talking about the possibility of native plants in formal settings (p 124), Tallamy cites the formal plantings of Mount Cuba Center in Greenville, Delaware. I believe formal plantings with native plants would be much more of a challenge within an eighth of an acre (p 280), containing a house and garage, with an eighth of an acre on either side and maybe behind, all owned by different people. I don't mean to belittle the idea of continuous native plantings across property lines (e.g. p 280), which seems very enlightened.

Among other issues Tallamy raises that would particularly interest me, is the use and further development of cultivars of native plants. Tallamy accepts the proposition that species forms and their cultivars are likely to be closely genetically related and hence likely have similar ecological relationships. From the internet, it is evident that not everybody agrees. At the level of nectar use, I have noticed that bees are attracted to the culver's root cultivar 'Fascination' and that Monarch butterflies use the purple coneflower culltivar 'Magnus'. Monarch milkweed species breeding preferences are reported, but one of our local gardeners has been able to extend the matter to a milkweed cultivar. He reports that Monarchs have bred in his garden three times, but always on the swamp milkweed selection 'Ice Ballet'. (Tomlinson unpubl.) This is in a garden that contains far more wild swamp milkweed and common milkweed than 'Ice Ballet'. This is just one of the many issues Tallamy brings into gardening focus.

This message was edited Jun 14, 2009 12:05 AM