Sweet Auburn: The Magazine of the Friends of Mount Auburn A Healing and Meditative Landscape | Page 11

Maple trees that had stood there for generations. This am- bitious undertaking, which involved lifting the trees (each weighing five tons) over the six-story library walls, was captured by local television crews and was facilitated by a major fundraising campaign led by the Friends of Mount Auburn. The introduction of these four large trees into Asa Gray Garden can be seen as the catalyst for the current effort to revitalize the garden, though the final planning for the renovation, led by the award-winning Halvorson Design Partnership, took many years to complete. Appropriately enough, those four Japanese Maples will anchor a planting scheme that celebrates the introduction of Asian plants into the United States and also illustrates what Asa Gray called “disjunct plant species.” Gray was the first person to notice the similarities between the floras of Eastern North America and East Asia and to come up with a plausible explanation for them. Although the climates of these two regions are similar, they are separated by many thousands of miles and the plants that they seem to have in common are often found nowhere else on earth. His idea was that the plant species descended from common ancestors that once ranged across the entire North Pacific region and the continental United States, but were then separated by the advance of glaciers during the Pleistocene Ice Ages. The species developed subtle differences during their long separation, while retaining a family resemblance. The significance of this idea cannot be overstated, as it became a cornerstone of the scientific understanding of how species arise. Gray’s work supported the highly controversial proposals of Charles Darwin, and his theory of species evolution. Together, the two men had a profound influence on the science of botany and our understanding of plants throughout history. The planting phase of the garden restoration, which will begin in the Spring of 2018, will feature some of the East Asian and Eastern North American counterpart species that Professor Gray studied, so that we can see for ourselves the similarities and subtle differences they exhibit. Examples Shortia galacifolia (left) and Shortia soldanelloides (right) Lindera benzoin (above) and Lindera obtusiloba (below) include the small graceful trees of the genus Stewartia, with their attractive camellia-like flowers and colorful peeling bark. There are already a pair of beautiful 70-year old speci- mens of Korean Stewartia (Stewartia pseudocamellia), growing on the southwest slope above Asa Gray Garden. The plans call for adding some Mountain Camellia (Stewartia ovata), a native of the Southeastern United States, and Orangebark Stewartia (Stewartia monodelpha), from the mountains in central Japan. Other examples include small trees (often called “snow- bells”) in the genus Styrax and the large-growing shrubs of Lindera. The genus Styrax is a fairly large one with most of its species occurring in Southeast Asia. The garden will feature the American Snowbell (Styrax americanus) and the Japanese Snowbell (Styrax japonicus), both with showy bell-shaped flowers that are mildly fragrant. Similarly, Lindera is a large genus with most of its species in Asia, and three in Eastern North America. Known as spicebushes for their aromatic leaves, they tend to flower in early spring and are perhaps best known for their stunning fall foliage colors. The local native Spicebush (Lindera benzoin) will be represented along with the Japanese Spicebush (Lindera obtusiloba). The example about which Asa Gray himself might have been most enthusiastic would be species from the genus Shortia. These rare herbaceous groundcover plants are found near mountain streams: four species in Asia and one in North America. The native, known as Oconee Bells (Shortia galacifolia), was an obsession with Gray. He hunted for what he called “perhaps the most interesting plant in North America” for 40 years before finally discovering it in North Carolina in 1879. 2018 Volume 1 | 9