(Tallahassee Democrat 8/19/10)
In Tallahassee, we have many fine non-native plants to use in our landscapes – camellia, azalea, crape myrtle all come to mind. The claims that native plants are easier to grow and require less water sometimes do not hold up.
For me, the main reason to choose native plants in the landscape is to promote the unique relationships between our native plants and animals, from the smallest microorganisms, insects and other invertebrates to birds and mammals. Simply put – what you plant in your yard makes a difference to wildlife. There are unique evolutionary relationships between native plants and wildlife that have developed over a very long time. Here are a few examples.
Red buckeye blooms in mid to late March, just in time for the return of ruby-throated hummingbirds from Central America. The hummingbirds drink nectar from red tubular flowers and, in return, provide pollination services for this native tree whose nuts are food for other wildlife.
Sweetgum trees have close relationships with several animals. When American goldfinch arrive in late fall or winter, they can be seen and heard high in sweetgum trees clinging to the prickly balls feasting on abundant sweetgum seeds. Many of our resident birds, like the Carolina chickadee, also depend on the seeds of sweetgum.
As valuable as seeds and fruit are to wildlife, native plants serve an even more important function. Native plants, from grasses and wildflowers to towering shade trees, form the base of the food chain. Our native insects are uniquely adapted to eat native plants; some are generalists and can eat a variety of plants, but many are specialists that can only digest certain types of leaves based on the chemistry of the plant. For instance, the luna moth would not be with us without the sweetgum tree and a few other native hardwood trees. Each female luna moth may lay 150 eggs, which then become 150 highly nutritious caterpillars, feeding chickadees, vireos, spiders and more. These in turn may be eaten by a snake, hawk or other predator. It is estimated that of the 150, only 2 or 3 survive to mate and lay eggs.
Most of our butterflies and moths depend on native plants, not just for nectar, but for sustenance while in the larval stage as caterpillars. For instance, spicebush swallowtails depend on sassafras, giant swallowtails on hoptrees and Gulf fritillaries on passion vine. Without their native food plants, these butterflies would cease to exist.
To make our yard more hospitable to wildlife, our goal each year is to increase the percentage of native plants. Over the last 18 years, we have transformed our front yard from a mediocre monoculture of lawn to a shady native oasis beneath a huge live oak on one side and a wildflower/butterfly garden on the sunny side. Judicious use of nectar rich non-natives like pentas, perennial salvias, Mexican sunflower and cardinal guard extend the blooming season of our butterfly/hummingbird garden and mix nicely with the native purple coneflower, ironweed, heliopsis, sunflower and other wildflowers.
We’ll always have room for a few azaleas, camellias and hydrangeas among the natives, but native plants provide the staff of life for wildlife. For further reading, I recommend Bringing Nature Home: How You Can Sustain Wildlife with Native Plants by Douglas Tallamy.