City Trees

Tree of Merit: Black Gum (Nyssa sylvatica) Are you looking for a drought tolerant tree with beauti- ful fall color, strong branch structure, adaptability to soil con- ditions, a long life span, susceptibility to very few diseases, and high wildlife value? Look no fur ther than the black gum (Nyssa sylvatica), also commonly called black tupelo. Black gum was SMA's Urban Tree of the Year in 2008 and deserves a renewed spotlight. This tree boasts stately elegance with an excurrent architecture that brings even scaffolding. Its glossy deep green leaves glow in summer and then bring some of the most vibrant and con- sistently performing hues of orange and red in fall. Black gum achieves a moderate height of 30 to 50 feet (9 to 15 m) in a cultivated setting, often more in a natural setting. Black gum is also noteworthy in its provision of victuals for wildlife; most apparent will be its small, matte purple drupe that the birds relish. This fruit ripens around the time the tree's autumn color develops, bringing about a medley of colors and bird activity in early fall. Less apparent are its small, inconspic- uous flowers, which are nonetheless prolific in their provision of nectar for pollinators. This nectar gives the tree its reputation as a top bee forage tree; the resulting prized honey has been culturally and commercially codified as "Tupelo Honey." (opposite) Black gum habit Photo: Courtesy Chicago Botanic Garden (above) Black gum fruits Photo: T. Davis Sydnor, The Ohio State University, Bugwood.org Black gum fall color Photo: T. Davis Sydnor, The Ohio State University, Bugwood.org Naturally occurring both in swamps and on dry hillsides, this tree is comparatively well-adapted to compacted, droughty urban soils. It is cold hardy from Zone 4 through 9 and occurs naturally in a large number of U.S. states, making it appropriate for many locales across the continental U.S. Black Gum has been considered a difficult tree to transplant—a notion that is perhaps the main reason we don't see more of it in the culti- vated urban environment. However, there is a growing chorus of professionals who consider the concerns around transplant- ability to be overblown. By transplanting in spring for B&B and either spring or fall for well-managed trees in containers or root-control bags, one can easily achieve strong survivability and vigor. As the tree matures, its evenly branched form will require little pruning and lowers the likelihood of branch failure. Add to that only minimal disease pressure and a very long life span (in nat- ural settings 250 years is common and 600 years is achievable) and you have a low-maintenance, low-cost tree that will share its many virtues for years to come. —Marty Frye, Arborist, Casey Trees 36 City Trees

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