Audubon in the Arboretum by Dee Smith

Fig. 1. In the eastern part of the United States, rows of shallow holes in tree bark are usually made by the yellow-bellied sapsucker (Sphyrapicus varius). They lap up the leaking sap along with any trapped insects.

Audubon in the Arboretum

When one thinks of John James Audubon’s work, it is often his depictions of wildlife that first come to mind. However, what makes his work so successful, in addition to his talent for illustrating birds, is that he painted his subjects in their natural, or native, settings. His paintings and journals contain some of the best images and descriptions of America as it existed in the early 19th century, and provide documentation of the native landscape of the time period.

Compared to the modern landscape, it was a very different America that Audubon experienced. He wrote of fields as far as the eye could see, almost impenetrable cane brakes, and wildlife in abundance. His America was one of wilderness, a land truly wild. Yet in his journals he also wrote of a “vanishing America” and expressed fear that it would be gone before he could record it all.

The plants and natural landscapes of the American wild were so intriguing that, as early as 1734, explorer, botanist, and horticulturalist John Bartram (1699–1777) was busily engaged in shipping thousands of plants and seeds from America to England. The plants were met with great excitement and sought out by plant collectors. Over time, English gardens became filled with American plants.

The plant trade grew rapidly, and in the midst of the plantcollecting and botanical network that stretched to every corner of the globe, “foreign” plants also arrived in America. Many non-native plants introduced in America in the 1700s and 1800s are well adapted and enrich

Fig. 2. Barred or hoot owl (Strix varia) in an Atlantic white cedar (Chamaecyparis thyoides)

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Fig. 3. Cumberland azalea (Rhododendron cumberlandense)

our landscape. A prime example is the beautiful camellia from China, which is, ironically, the state flower of Alabama. Is it possible to imagine a Southern landscape without crepe myrtles from the Indian Subcontinent or azaleas from Japan? Even though North America has an equally beautiful native azalea, it is far less prevalent in the landscape than its Asian cousin.

However, not all of these introductions have enriched our landscape. Some have become invasive and outcompete and displace our natives. There are several costs associated with the introduction of some of these non-native plants. A direct cost is the millions of dollars spent each year in an attempt to control damage to local habitats. Another cost of introducing foreign plants to our local environment is that over time, native species can be overwhelmed by non-native, invasive species. When this happens, our ecosystems become imbalanced and don’t function properly. All creatures in the wild depend directly or indirectly on plants for food, but many foreign plants provide little, if any, support for native plant eaters, like insect herbivores, or the leaf-eaters. They just don’t eat the nonnative plants.

Initially, this may seem to be a positive: aren’t plants that insects don’t eat what we want in a landscape? The answer is no, because insect-resistant plants can seriously disrupt the food chain. Since so many animals depend partially or entirely on insect protein for food, a land without insects is a land without most forms of higher life. Without insects, our food crops aren’t pollinated and birds can’t feed their young. Ecosystems are highly complex and rely on a variety of species to survive. When we remove species from our ecosystems, we risk their complete collapse.

Adult Zebra swallowtails lay their eggs on pawpaw leaves

Zebra swallowtail provide a food source for bird young Zebra swallowtail larva only eat pawpaw leaves

Insects are either generalist, meaning they eat a wide variety of plants, or specialists that rely on only one food source. What many specialists eat is toxic to others. They have co-adapted with their food source and developed traits that allow them to detoxify the plant chemicals. Whichever they are, most eat plants they have shared an evolutionary history with—our natives. The pawpaw leaf is the sole support for the zebra swallowtail, while a single oak or black cherry tree can support literally hundreds of species. Without the complex interactions between plants, animals, and insects we’ll have a less rich and balanced landscape. We are learning that the plants we choose for our own yards can make a significant impact on establishing more biodiversity and be a functional part of the web of life.

American plants, and particularly native Southeastern plants, are a part of our local history. They tell us where we are and give us a sense of place. The plants shown in the prints in this guide—and planted in the Davis Arboretum—are the same plants Audubon and his fellow naturalists encountered in their travels. They are native to this region and grow and thrive here. Audubon would have been attuned to the rhythms and timing of nature’s events, such as the migration schedules of the migratory birds he painted. Many of us today pay little attention to this connection and are essentially unaware of the effects that plant species around us have on the other species that surround us. For a very long time “gardening” has been done with an eye purely toward aesthetics, planting for pleasing combinations of colors and textures, seasonal interest, and repeating patterns. What a dramatic difference could be made to the biodiversity of a place if more thought were given to planting for the benefit of the native species with which we share our space. Fig. 4. Mockernut hickory (Carya tomentosa)

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The Davis Arboretum houses the living collections in Auburn University’s Department of Biological Sciences, and it is a carefully catalogued living museum. Part of its mission is to collect and display the plant species that are native to Alabama and the Southeast, and by doing so create ecosystems that support other native organisms. Somewhere along the way, Americans have come to expect our landscapes to look a certain way, to conform to an artificial idea of perfection, embracing clipped hedges and manicured lawns. The pesticide arsenal is reached for at the first sign of insect invasion.

These contrived gardens have little in common with a living, balanced system where all things interact. Contrary to popular belief, a pest-free and sterile garden is not healthy, and it ceases to function as a community of interacting organisms. Audubon’s illustrations and writings are windows onto a landscape that may have changed dramatically but, in part, is still present.

He reminds us of what once was, and that we are part of a web that connects us to our history and to the natural world, a web that needs to remain intact.

Dee Smith

Donald E. Davis Arboretum College of Sciences and Mathematics, Auburn University

Figs. 5 and 6. Darby's Pond, pictured here in 1885 (left), would become a central feature in the Davis Arboretum in 1963 (above).

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